How Technology has evolved the Online Casino Industry?

Hello everyone, welcome to today article which we are going to have a look at how technology has evolved the online casino industry. Some of you might be having knowhow on what casino industry is and some might be having partial or no knowledge at all. So, we are going to start with simple things as we advance our topic of discussion further. You should also have a look at the Technology behind Online Casinos.

Definition of the global casino industry

The global casino industry is an industry that is made of facilities that involves predictions of outcomes of the final result that will be obtained after an invent has passed. The predictions are made before the event has started. It is made up of the gambling activities such as the gaming machines and the table wagering boards. it is also a common thing for some of these facilities to provide dinning, lodging and the beverage services to their customers. This industry has evolved to an online modernized activity. The online facility has become the most used one especially in this era of corona virus where lockdowns have really affected the physical appearances in the normal global casinos. Online facilities have offered players and bookies a very momentous offer where they can play the game at any place of their comfort.

The first online casino which was referred to as Inter-casino was launched in 1996 and at this time nobody had an idea of what awaited the casino industry. Bookies never thought that one day the industry would evolve to what it is today. Currently, the online casino industry is worthy over 45 billion US dollars something that is still forcing more investors to put their capital in this new area of business and entertainment. You can imagine after the launch of the first online casino industry, in the same month, there was a raise in the number to 15 and a year later, more than 150 online casinos had been launched. Actually, this was the area where investors had started seeing some great potential.

Since the industry crossed the one billion net worth mark in 1998, there have been new inventions and innovations that have led to drastic change and growth in the online casino industry. More technological advances have been made which has led to more players feeling comfortable in joining the industry. This article will focus on how technology has impacted on the online casino industry.

Multiple payment options

Multiple payment option is one of the areas that have greatly improved the online casino industry. Players can now deposit and withdraw money from sites within seconds. This payment systems introduction has lowered the cost incurred by clients and also fastened the process. Several cashless payment methods have also hit the market. These payment methods such as PayPal, Skrill, mobile money and Wire Transfer, etc have impacted greatly on how customers receive their winnings from the booking sites. You can check on OBLG to take note of all the casinos that offers their payment through PayPal which is the most commonly used universal payment methods by the majority of the bookies especially in Europe and America. Moreover, because of this online payment system, casinos also offer no deposit free spins offers, in order to attract customers.

Although landless betting has a limited amount that a client can play with, the online casino has offered a lot of options that can be used in the process and this has led to the expansion of the casino industry. One greatest thing that happens in technology is that you can adapt to new trend very quickly. Currently, cryptocurrency is taking over as the means of payment because with it you are guaranteed of great financial security and anonymity. Most popular cryptocurrency is the Bitcoin and it has offered very strong facility where even governments are unable to track owners of the casinos or even the players. With this cryptocurrency being used as a mode of payment, the casino industry has grown internationally simply because players from restricted countries can play in anonymity and get their winnings in form of cryptocurrency.

There has also been a shift in focus where most online casinos are introducing casinos that operate in the blockchain technology whereby there is an outcome of better features and makes the future of the casino industry look great.

Choice and variety

With new trend in the area of technology, there have been development of the multi-dimensional approach across the casino industry. There has been great input in the development of the games that offers great and clear features to the players and the viewers.

With online gambling, bookers can feel a redefined industry. When you look at the betting sites, you will realize that they have been customized in a manner that it has a very powerful interface which offers the gamers a very welcoming experience while carrying out the gambling at the comfort of their wish. The introduction cool visuals and the tense atmosphere which tries to mimic the situations in real-life has made the online casino industry more and more beautiful. This actually evidence from the growth of the numbers on the gamblers who are who prefer doing their gambling online as compared to those who prefer doing it manually or in the traditional land-based gambling. For example, most online gambling industry have decided to introduce the eSports games in their online gambling platform and this shows the potential of that innovation has made in the gambling industry.

The variety of the games available in the online casino platform has also led to the increased number of gamers joining the gambling industry where some online casinos offer more than 2000 games that a gamer can choose from. The vast options of the games that are available ensure that gamers are never bored due to the availability of too many games options to choose. In some occasions, virtual reality has been involved in making this online gaming industry a reality. The use of this high technology glasses has made gamblers experience more entertainment as they feel inserted into the world of different reality. Users are able to have a real time interaction that is based on the traditional land-based casino interactions.

Customer support system and security

Despite the great growth in the online gaming industry, it comes home with some disadvantages especially on matters security since it is accompanied with a lot of attacks that are directed towards the gamers. This frequent security attacks are more as compared to what is experienced in the traditional land-based casino. Since the digital information is always very sensitive, it is the duty of the casino site to keep the information very safe lest it falls in the hands of the wrong person. The sensitive personal information that is required for online casino can be used for identity where the client can lose a lot of money through hacking. Online casinos have been forced to use new technology in securing their sites in order to protect their clients from insecurity that might occur.

Some online casinos have even gone a step higher whereby they use the artificial intelligent to improve the security of the site and ensure that they monitor every movement that is made on the sites. There has also been a way where users have to provide the 2FA authentication to ensure that only authorized members get access to the sites.

Customer support has also moved a notch higher with the advent of new advanced ways of solving customer issues in the online casino platforms. In the online casino platforms, you will come across emails, call centers and even live chats which have been introduced in the recent years to improv on customer care services. Some of these casinos have a way of offering 24/7 customer care services and this is done to prove to the customers that they are gambling in a very safe place. This proper customer care services have led to the expansion of the casino industry globally.

The mobile casino industry

The advent of the smartphone industry has also increased the growth in the online industry. Today, the largest population of the world have a smartphone in their pocket and this has led to the people participation more in the online casino games and gambling. Online casinos have taken advantage in the growth of the smartphone owners and have come up with sites that are mobile friendly giving their players a very fascinating environment to entertain themselves. The mobile casino games are very revolutionary as players can get access to the games at any time and any locations and this has made it very convenient to the gamers the mobile phones have introduced portability to this industry.

Better marketing

Some few years ago, the gamers used to visit the betting shops to play games. With the introduction of the online casino, it has become do possible for the games to rich people easily and in any location of this world. Some companies have moved the impact higher by organizing gaming competitions that involves millions of people which could not be achieved in the traditional hall because of the spacing and difficulty in managing the outcome. The online casino has actually introduced the new investment opportunity for the people. This online casino has actually introduced new technology trends in order to place itself in a position which can rival the competitors and also give the pundits an improved gaming experience. They have come up with very user -friendly interfaces that come in with several important features. Some of these sites use artificial intelligent to settle and update results and games too. All these activities are being done to ensure that the online casino site has more clients joining.

Artificial intelligent

Modern online casinos have gone into another level whereby the use of artificial intelligent have revolutionized the industry. Artificial intelligence such as the use of the chatbots have been used to help the gamblers in placement of the bets. The same artificial intelligence has been used by the sites to help customers in the processing of their payments from the bookies and also process withdrawal request for the clients. The bot is very important in this industry because they can offer unlimited customer support. The artificial intelligence has also found use in the online casino industry where the gamers have an interest in playing against the machines instead of playing against the other gamers. Also, the Sportbooks have been using various artificial intelligence mechanism to help the users of the various websites find the various icons and learn how to use the sites.

Mobile phone applications

The smartphone, tablets and the internet industry has made major technological impact in the area of the online casino industry. Statistics show that in 2012 there was a great improvement in the use of the online casino by 12% globally. This improvement was introduced due to the revolutionization of the smartphone and the internet industry. Now close to over one hundred and sixty million pundits visit online casinos on their phones using the mobile phones applications. The mobile gambling is said to be contributing at least 50% of the revenue that is generated from the gambling industry. The mobile applications have greatly impacted on the growth of the online casinos industry.

In conclusion, the online casino industry has grown to a greater extent through the introduction of so many trends in the areas of money transfer, online payment methods, the introduction of artificial intelligence, the great extent to which the mobile phone application industry has grown higher, the introduction of better marketing strategies, better customer support and security systems. With all these, the industry has grown to something else, something better and something magnificent attracting more bookies worldwide.

Simulating Advanced Logic Gates using Ladder Logic Programming

Hello friends! I hope you are all very well! I am so happy to meet you today to continue learning and practicing PLC ladder logic programming. In an earlier part, we already have gone through the very basic logic gates of “AND”. “OR”, and “NOT”. Today we are going to resume the simulation of logic gates. We have started and gone through simulating the basic logic gates which are “AND”, “OR”, and “NOT” as they are the most important basic logic gates by which we can form other logic gates. However, because the logic of large-scale projects is getting more and more complicating, a lot of time we have to use the other functions to do tasks faster. For example, we have shown in the logic gates article that, XOR can be used to compare two inputs and check if they are equal or not. On the other hand, someone may say, oh we can do XOR by using the basic three gates of “AND”, “OR”, and “NOT”. That’s correct. So why do we need to go learning other logic gates when we can implement them by using that three basic logic gates. Well! That is a very good question.

Working in ladder logic programs is getting further complicated especially for large-scale projects. So, it is very beneficial to know shortcuts for writing ladder logic simpler, more readable, and easier for others to develop. Using this variety of logic gates, enrich the logic and fluency of writing the logic in different situations. For example, using XOR logic is very common for comparing two inputs to decide if they are equal or different. Therefore, we found that it is crucial to go through all logic gates and do simulations for them all in this tutorial. for coherently we get the knowledge to use them fluently in ladder logic programming to solve different logical problems and scenarios. There are seven basic logic gates which are: “AND”, “OR”, “NOT”, “NAND”, “NOR”, “XOR”, and “XNOR”. We have gone through “AND”, “OR”, and “NOT” logic gates including simulation work. So let us go through the other four gates for learning and practicing all basic logic gates.

The "NAND" Logic Gate

The “NAND” logic gate is the invert of the “AND” gate like you invert the output of an “AND” logic gate as shown in Fig. 12. Table 5 lists all combinations of the inputs and the output of the “NAND” logic gate.

Fig. 12: NAND symbol

Table 5: the truth table of the “NAND” logic gate

Input A Input B Output
0 0 1
0 1 1
1 0 1
1 1 0
 

In addition, the timing diagram of a “NAND” logic gate is shown in fig. 13, it shows the output goes low when both of the inputs A and B are true which is the inverse of the “AND” logic gate. Also, Fig. 14 shows a ladder logic of a “NAND” logic.

Fig. 13: The timing diagram of the “NAND” logic gate

Fig. 14: Ladder logic sample of a “NAND” logic

NAND Logic in PLC simulator

The NAND logic gate can be considered as the invert of the “AND” logic gate. So as listed in table 1, the truth table of AND and NAND logic gates shows how the NAND gate is the reverse of the AND gate. Also, it shows the NAND gate should come out to your mind when you want the output always low except when both inputs A and B are high.

Table 1: the truth table of the AND versus NAND logic gate

The NAND gate can be implemented by connecting the negate of the output in series to the inputs A and B. Another way to implement NAND is by inverting both inputs and connecting them in parallel as shown in fig. 1. Rung 1 and rung 2 respectively.

Fig. 1: The NAND ladder logic in two ways

 

Let’s test our ladder logic in both methods. According to the truth table of NAND gate, we have four test cases. figure 2 shows the first test case when both inputs A and B are false. In this case, the output should be true as shown in fig. 1.

Fig. 2: NAND ladder logic when both inputs are false

figure 3 shows the second test case when inputs A goes true while B is false. In this case, the output should be true as shown in fig. 3.

Fig. 3: NAND ladder logic when input A is false and input B is true

Figure 4 shows the third test case when inputs B goes high while B is low. In this case, the output should be true as shown in fig. 4.

Fig. 4: NAND ladder logic when input A is true and input B is false

Figure 5 shows the last test case when both inputs A and B become high so the output goes false as shown in fig. 5.

Fig. 5: NAND ladder logic when both inputs are true

Thanks to performing the simulation of the NAND gate, we now can conclude that we should be looking for a NAND logic when we want to shut down an actuator i.e. motor whenever two inputs are in a true logical state simultaneously. For a practical example, when we have three pumps and we want to run them in the mode of two of three. There should be only two of the three pumps to run at any time. In that case scenario, the run condition of any motor can be a NAND of the status of the other two motors.

The “NOR” Logic Gate

The “NOR” logic gate receives two inputs and has one output. It is the same as the invert of the “OR” logic gate. Like you follow the output of an “OR” gate by a “NOT” logic gate. Fig. 15 shows the symbol of a “NOR” gate. In addition, the truth table is expressed in table 6. It shows the output becomes false only when one of the input A or input B or both goes high which is the reverse logic of the “OR” logic gate.

Fig. 15: The symbol of “NOR” gate

The “NOR” logic gate can be formed by connecting the “OR” logic gate to the inverter “NOT” logic gate. Or by inverting the inputs by using “NOT” logic gates and connecting them to the “AND” logic gate as shown in Fig. 16.

Fig. 16: structure of “NOR” logic gate

Table 6: the truth table of the “NOR” gate

Input A Input B Output
0 0 1
0 1 0
1 0 0
1 1 0
 

Figure 17 shows an example of a ladder program for implementing the “NOR” logic gate. It shows that the “NOR” gate can be implemented in ladder logic by connecting two contacts of type NC in series.

Fig. 17: A sample ladder for a “NOR” logic gate

On the other hand, the timing diagram of the “NOR” logic gate is depicted in Fig. 18. It shows the output is false as long as either input A or input B or both are true.

Fig. 18: The timing diagram of the “NOR” logic gate

NOR logic gate in PLC Simulator

This logic gate can be considered as the negate of OR as you can notice in the truth table as listed in table 2. You can now feel when we may need to use the NOR logic? Yes! Exactly you want it when you design for output which is all time off except when both inputs are false.

Table 2: the truth table of NOR versus OR

Input A Input B OR NOR
0 0 0 1
0 1 1 0
1 0 1 0
1 1 1 0
 

Figure 6 shows two ways to implement the NOR logic in ladder logic. To make that happen, we connect the invert of the two inputs in series to the output as shown in the top part of fig. 6. The other way is to connect the two inputs in parallel to form OR and then connect to negate the output as shown in the lower part of fig. 6.

Fig. 6: The ladder logic of NOR logic gate

Let’s practice simulation of the NOR gate, in fig. 7, the first test case is when both inputs are false, the output is true as shown in fig. 7.

Fig. 7: The Simulation of NOR ladder when both inputs are false

Figure 8 shows the second case when input A is true and input B is false, the output is false as shown in fig. 8.

Fig. 8: The Simulation of NOR ladder when input A is true and input B is false

Figure 9 shows the third test case when input B is true and input A is false, the output is false as shown in fig. 9.

Fig. 9: the Simulation of NOR ladder when input B is true and input A is false

Figure 10 shows the last test case of NOR ladder logic, it shows the output is false

Fig. 10: The Simulation of NOR ladder when both input A and B are true

One practical example of using the NOR logic is that, imagine friends we drive some machine with two motors. And it is required to have at least one of them or both are running all the time otherwise alarm should be energized. The NOR logic is the best to manage that alarm to get energized if and only if both motors are off.

The Exclusive OR "XOR" Logic Gate

Despite this logic gate having two inputs and one output like the “AND” and “OR” logic gates, this logic gate is a bit more complicated than the previous logic gates. Table 4 lists the truth table including all combinations of the inputs and the output. By noticing the truth table of the XOR logic gate, you can see the output becomes low when the two inputs are equal like both are high or both are low. But the output goes high when there is a difference in the state of the two inputs. Imagine my friend, how much this logic gate is very beneficial for comparing two signals.

Table 4: The truth table of XOR logic gate

Input A Input B Output
0 0 0
0 1 1
1 0 1
1 1 0
 

On the other hand, Figure 10 shows the symbol of the XOR logic gate and its schematic. See how the basic logic gates OR, AND, and NOT can be utilized to build the logic of XOR logic gate.

Fig. 10: The XOR logic gate symbol

Figure 11 shows a sample of a ladder logic program that implements XOR logic. In addition, it shows the timing diagram of the inputs and output, it shows the output goes high when there is a difference between the two inputs and becomes low when they are equal i.e. both are low or both are high.

Fig 11: Sample of the ladder logic for XOR logic and the timing diagram

XOR Logic Gate in PLC Simulator

The XOR is used to compare two signals if they are equal or different. Table 3 lists the truth table of the XOR. It shows that the output comes to true when inputs are different and becomes false when they are equal.

Table 3: The truth table of XOR logic

Figure 11 shows the construction of XOR ladder logic. It shows that it is composed of, two parallel branches and each branch is forming AND logic of the two inputs in the opposite logical state.

Fig. 11: The ladder logic of XOR

Figure 12, shows the simulation results of XOR when input A and B are false, the output is false.

Fig 12: Simulation of XOR ladder when both inputs are false

Figure 13, shows the simulation results of XOR when input A is true and input B is false, the output is true. Fig 13: The Simulation of XOR ladder when input A is false and input B is high

Figure 14, shows the simulation results of XOR when input B is true and input A is false, the output is true.

Fig 14: The Simulation of the XOR ladder when input B is true and input A is false.

Figure 15, shows the simulation results of XOR when input A is true and input B is true, the output is false.

Fig 15: The Simulation of XOR ladder when both inputs are true

In a conclusion, the XOR logic in simulation shows that the output is low whenever both inputs are equal and goes high when the inputs are different in the logical state. A very good practical example for utilizing the XOR logic is that imagine friends we have a motor that is energized by two different destinations, and it should be requested by only one at a time. So we can get the run signal from the XOR of the two input switches. So, the only case to run the motor is by requesting from one source.

The “XNOR” Logic Gate

This logic gate is the invert of the XOR gate. So it is equivalent to applying an inverter to the “XOR” logic gate. Table 7 lists the combination of its two inputs and its output. It shows clearly that, the output becomes true when inputs are equal i.e. both inputs are true or both are false.

Table 7: the truth table of the “XNOR” logic gate

Input A Input B Output
0 0 1
0 1 0
1 0 0
1 1 1

Fig. 20 shows the symbol of the “XNOR” logic gate, it shows clearly how it is the invert of the XOR logic gate. This logic gate is very useful to validate if two signals are equal or not.

Fig. 20: The symbol of the “XNOR” logic gate

On the other hand, Fig. 21 shows a sample ladder logic of an “XNOR” logic gate implementation. It shows that there are only two ways to have the output in the TRUE state which are by setting both inputs TRUE or set both FALSE.

Fig. 21: A sample ladder logic for “XNOR” logic

Fig. 22 depicts the timing diagram of the inputs and output of the “XNOR” logic gate and clearly shows the output goes high when both inputs have the same state.

Fig. 22: the timing diagram of the “XNOR” logic gate

XNOR Logic in PLC Simulator

The XNOR is the invert of the XOR and it is used to compare two input signals. Table 4 lists the cases of the truth table of XNOR logic. It shows the output goes high when both inputs are equal i.e. both are high or both of them are low.

Table 4: the truth table of XNOR logic

Figure 16 shows the construction of XNOR ladder logic. It shows that it is composed of, two parallel branches and each branch is forming AND logic of the two inputs in the same logical state.

Fig 16: XNOR ladder logic

Figure 17, shows the simulation results of XNOR when input A and B are equal i.e. both are false, the output is high.

Fig. 17: The Simulation of XNOR ladder when both inputs are false

Figure 18, shows the simulation results of XNOR when input A is true and input B is false i.e. they are different. So the output goes false.

Fig. 18: The Simulation of XNOR ladder when input A is false and input B is high

Figure 19, shows the simulation results of XNOR when input A is false and input B is true i.e. they are different. So the output goes false.

Fig. 19: The Simulation of the XNOR ladder when input B is true and input A is false.

In the last case when both inputs A and B are high as shown in Fig. 20, the output becomes true.

Fig. 20: The Simulation of XNOR ladder when both inputs are true

We can conclude that the XNOR is marked by the true status of its output whenever both inputs are equal and vice versa. One of the most common scenarios for the best practice of XNOR is the protection of the operator's hands in the cutting machine. In that machine, the command for running the knife driving motor is an XNOR of two switches on the left and right hand of the operator. In that way, it is guaranteed that to run the motor, the operator should use both hands at the same time.

What’s next

I am very pleased to see you up to this point of our tutorial, Now you are familiar with all logic gates and practiced their logic on the simulator. In addition, you can feel the importance of mastering all these logic gates to ease your programming and enrich your programming skills. In the next tutorial, we are going to go deeply through the edge signal including rising and falling edge. We are going to introduce the benefits of these edge signals and how they can be utilized in ladder logic programming to solve a lot of problems. So be ready for more learning and practice with simulation in ladder logic series.

ESP32 Hall Effect Sensor in Arduino IDE

Hello readers, I hope you all are doing great. Welcome to Section 5 of the ESP32 Programming Series. In this section, we are going to interface different Embedded Sensors with the ESP32 Microcontroller Board. ESP32 development board is featured with some inbuilt sensors(i.e. hall effect sensor, capacitive touch sensor) so, in the initial tutorials of this section, we will explore these built-in ESP32 sensors and in the later lectures, we will interface third-party sensors with the ESP32.

In today's lecture, we will discuss the working/operation of the ESP32 built-in Hall Effect Sensor. Hall Effect sensor is used to detect the variation in the magnetic field of its surroundings. So, let's first understand What's Hall Effect:

Where To Buy?
No.ComponentsDistributorLink To Buy
1ESP32AmazonBuy Now

What is the Hall Effect?

The Hall Effect phenomenon was first discovered by Edwin Hall in 1879. When current passes through a conductor, the electrons move in a straight line and thus the voltage difference across the conductor's surface remains zero, as shown in the below figure:

However, when a magnet is placed near the current-carrying conductor in a way that the direction of the magnetic field is perpendicular to the flow of current, the electrons get diverted and don't follow a straight line, which results in generating a small potential difference across the conductor's surface, as shown in the below figure:

This small potential difference generated because of magnetic field presence is called Hall Voltage. This magnetic field influence over the current-carrying conductor is termed the Hall Effect.

Hall Effect Sensor

A Hall Effect Sensor is a non-contact type embedded sensor, used to detect the presence & intensity of a magnetic field in its surroundings. Different third-party Hall Effect Sensors available in the market are shown in the below figure:

  • A normal Hall Effect Sensor Pinout consists of 3 Pins i.e.
  1. Vcc: Normally +5V, few +3.3V are also available.
  2. GND: We need to provide Ground here.
  3. OUT: The Output Pin to give the sensor's response.
  • When a perpendicular magnetic field is placed near a Hall-effect sensor, it changes the status of its Output Pin.
  • The analog Hall Effect Sensors can also detect the strength of the magnetic field i.e. greater the magnetic field greater will be the sensor's output or voltage deviation.

Applications of Hall Effect sensor

  • In an Automotive system, Hall Sensors are used to detect speed, distance, position etc.
  • Used in Proximity sensing.
  • Used in Current sensing.
  • Used in Anti-lock braking system.
  • Used in Internal combustion engines to assist with ignition timing.
  • To switch an electric circuit ON and OFF.

Hall Effect Sensor in ESP32

In ESP32, the Hall effect sensor is located inside the ESP-WROOM-32 metallic cover. As the Hall Effect sensor is a non-contact type, it doesn't have to be in contact with the magnet. We just need to place the magnet above this metallic sheet and the ESP32 Hall Effect sensor will detect it.

Programming ESP32 Hall Effect Sensor using Arduino IDE

To understand the working of the Hall sensor with ESP32, let's test the builtin ESP32 example:

  • You can find the code through File> Examples> ESP32 > Hall Sensor, as shown in the below figure:

Arduino IDE code

Here's the code for this ESP32 Hall Sensor example:

int val = 0;

void setup()
{
   Serial.begin (9600);
}

void loop() 
{
   val = hallRead();
   Serial.print ("sensor value = ");
   Serial.println (val);//to graph

   delay(100);
}

Code Description

The code is quite simple, where the hallRead() function is called to read the hall sensor value, store it into a variable and then print it on the Serial monitor. Finally added a small delay to get the next value. Let me explain the code line by line for the beginners:

Variables Declaration

  • The first step will be the declaration of an integer-type variable to store the hall sensor value. The initial value assigned to the variable is zero.
int val = 0;

Setup() Function

  • Inside the setup function, the only task is to initialize the serial port at a 9600 baud rate for serial communication.
void setup()
{
   Serial.begin (9600);
}

Loop() Function

  • Inside the loop function, we called a function ‘hallRead()’ to read the sensor value and store those readings into the variable ‘val’.
  • Printed the sensor readings on the serial monitor or serial plotter using serial.println() function.
  • A delay of 0.3 sec is added at the end.
void loop() 
{
   val = hallRead();
   Serial.print ("sensor value = ");
   Serial.println (val);//to graph

   delay(100);
}

ESP32 Hall Effect Sensor - Testing

  • After successfully uploading the code into ESP32, open the serial plotter or serial monitor to monitor the results.
  • Place a magnet near the ESP32 board.
  • The sensor reading will increase/decrease depending on the magnet pole(i.e. North or South Pole) facing the Hall sensor.
  • Now click on Tools > Serial Plotter to visually analyze the sensor's output.
  • The Serial Plotter of our project is shown in the below figure:
  • As you can see in the above figure, the sensor is giving negative output when facing the North Pole of the magnet.
  • In the case of a South Pole, the sensor's output is positive.
  • In the absence of a magnetic field, the sensor's output is almost 0.
  • The distance between the magnet and the Hall sensor decides the amount of potential difference generated.
  • The greater the distance between the two, the smaller the hall voltage or potential difference will be.
  • We have attached an image from the Arduino IDE serial monitor for your reference.

This concludes the tutorial. I hope you found this helpful, test it out and if feel any difficulty, let me know in the comments. In the next tutorial, we will have a look at another built-in sensor of ESP32 i.e. Capacitive Touch Sensor. Thanks for reading.

Car Parking System with Automatic Billing using Arduino

Hi Geeks, welcome to our new project. Our new project is one of the most common issues you’ve seen in your cities. In this project, we are going to make a car parking system with automatic billing. In the entire world, there are an estimated 1.4 billion cars on the road, which is absolutely great news if we are considering the development of the Automobile industry. But the most serious issue is that the number of cars exceeds the number of available parking places, resulting in traffic congestion. Damaged cars due to this lack of space, fewer parking locations, lack of parking signage, informal parking, and overcharging for parking are just a few of the issues.

People are still choosing manual parking methods, which have a number of drawbacks, such as searching for a vacant spot in a parking lot without knowing if the lot is full or not, resulting in time and fuel waste. Vehicle safety is also a concern that may be addressed. We've all been in a position when we've spent a long time looking for parking at a location just to discover that none is available. You would think that if you knew the slots were full, you would've ended up finding another parking spot.

Based on these scenarios, we came up with the idea of a Car Parking System with Automatic Billing which will also reduce manpower such as security, booth attendants, etc., required in parking lots. Everything in the modern day is automated, and with this project, we can automate this procedure using simple electronics components and Arduino. Let's get started.

Where To Buy?
No.ComponentsDistributorLink To Buy
1DS1307AmazonBuy Now
2Keypad 4x3AmazonBuy Now
3LCD 20x4AmazonBuy Now
4Arduino UnoAmazonBuy Now

Software to install:

Instead of using real components, we'll use the Proteus Simulation tool to design this project. It's also a good habit to experiment with simulations before attempting to build everything with real components. By simulating an issue that may develop when working on actual components, we may identify the problem and avoid any damage to our components.

Proteus is an interesting software that lets you model and build electronics circuits. Despite having a huge library of electronics components, Proteus software lacks pre-installed modules such as Arduino boards, Ultrasonic sensors, RTC modules, LCD modules, and so on.

Now, we’ll start installing the libraries, which is needed for our project:

By clicking the button below, you can download the entire project, including Proteus Simulation and Arduino Code.

Project Overview:

These are required components for Accident Detection, which are as follows:

  • Arduino Uno: Arduino Uno is a development board from the Arduino family, which is the main component of this project and acts as the brain. The Microcontroller i.e., Arduino is responsible for the decisions that are going to be processed in the project.
  • 20X4 LCD display: It is used to display the information regarding parking slots and shows the amount that has to be paid by the driver at the Check out time from the parking lot.
  • Ultrasonic Sensor: It is used to calculate the distance from the car to the entry gate and detects that a car has reached near the gate.
  • RTC Module: Real-Time Clock Module is used to calculate the time and plays a key role in determining the total amount for the parking slot.

Components Needed:

  1. Arduino Uno
  2. LCD Module
  3. Ultrasonic Sensor
  4. Keypad 3x4
  5. LED’s
  6. RTC Module

Components Details

Arduino Uno:

  • Any Arduino development board can be used in this project, however, we'll be using Arduino UNO development boards. The Arduino UNO is a programmable, open-source microcontroller board from the Arduino series.
  • It contains an ATMega328P microcontroller from Atmel, which has an 8-bit RISC processing core and 32 KB of flash memory.
  • The Arduino UNO includes 14 digital I/O pins i.e., D0 - D13, with a resolution of 10 bits, including 6 PWM pins and 6 analog I/O pins (0-1024) i.e., A0 - A5.
  • Only one hardware UART peripheral pin, one I2C peripheral pin, and one SPI peripheral pin are available on the Arduino UNO (however we can use other pins for UART communication using the SoftwareSerial package in Arduino).
  • The Arduino UNO can be powered from a voltage range of 7 to 12 volts, the voltage regulator embedded inside the board will reduce the excess voltage. however, not more than 9 volts is suggested since it might harm the Arduino board.
  • A USB-B cable (the same cable that we used to upload the sketch to Arduino UNO), a DC power jack, and the Vin pin on the board may all be used to power Arduino UNO.
  • Using the Arduino IDE Software, the sketch is written and uploaded to the Arduino UNO. It is completely free, simple to comprehend, and easy to combine with a variety of electronic components.

LCD Module:

In this project, an LCD display is used to present the information to the user.
  • LCD stands for Liquid Crystal Display, and it is a type of display that is made using Liquid Crystal technology.
  • LCDs come in a variety of sizes; in this project, we utilized a 20X4 size.
  • The 20X4 indicates that it can show 80 ASCII characters at once.
  • The LCD has 16 pins. In which the necessary pins are connected in the circuit.
  • It contains eight data pins, one Read/Write select pin, one Register mode pin, one Enable pin, two backlight pins, two power supply pins, and one contrast control pin.
  • In the LCD, there are primarily two types of registers: Command Register and Data Register.
  • When the RS(Register Select) pin is set to logic high, the data register mode is selected, and when it is set to logic low, the command register mode is selected.

The RS pin will be set to logic high to display the data on the LCD.

Ultrasonic Sensor (HR-SR04):

  • The HC-SR04 ultrasonic sensor employs SONAR to estimate the distance of an object.
  • The ultrasonic sensor sends out a signal wave that has a frequency of about 40 kHz, with a high pitch that humans are unable to hear.
  • From 2 cm to 400 cm (1" to 13 feet), it provides the detection of objects with high accuracy and the pulse will not be disturbed by sunlight or any climate conditions.
  • It consists of four pins, Trig, Echo, VCC, and GND.
  • The operating voltage of an Ultrasonic sensor is 5V. We can connect the VCC pin of the sensor with 5V output in Arduino and the sensor will work perfectly.
  • Ultrasonic sensors work on the principle of sound wave reflection.
  • The trig pin works as an ultrasound transmitter which emits the high frequency sound waves in pulses. And the echo pin works as an ultrasound receiver. It receives the reflected ultrasonic waves which are bounced back from the object.
  • We calculate the distance from the object and the sensor by measuring the time taken between the transmission and the reception of the signal.
  • To measure the distance of sound traveled from trig to echo,

Distance = (Time x SpeedOfSound) / 2.

Speed of Sound: 340 meters per second i.e., 0.034
  • The easiest way to calculate the distance in cm is using this formula,

Distance in Centimeters = (( Time taken by pulse signal (in microseconds) / 2) / 29)

Keypad 3x4:

  • A keypad button is used for user input.
  • The keypad's buttons are arranged as a matrix of 3x4. Which means it has four rows and three columns.
  • They work on the principle of membrane keypads. They are very flexible and feel like a push button.
  • The switch between a column and a row trace is closed when a button is pressed, allowing current to pass between a column pin and a row pin.
  • A copper padding and line beneath the pad connects each switch in a row to the other switches in the row.

RTC Module (DS1307):

  • The DS1307 IC is a low-cost, high-accuracy RTC that uses the I2C protocol as an interface.
  • The DS1307 features a backup battery mounted on the rear of the module to maintain track of time even if the main power supply is disconnected.
  • When necessary, the chip shifts between the primary and backup power sources.
  • The RTC records information such as seconds, minutes, hours, days, dates, months, and years.
  • This module includes a Reference clock, programmable Square wave output(SQW), SCL, SDA, VCC, and GND.
  • Automatic Power-Fail Detect and Switch Circuitry
  • Low Power Operation Extends Battery-Backup Run Time.
  • The RTC module works on operating voltage 5V.

Proteus Simulation of Car Parking System:

Now, it’s time to start the design of the Proteus Simulation of our Car parking system

  • Before you begin designing, make sure Proteus is installed on your computer and that you have downloaded all of the necessary libraries.
  • We'll need Arduino libraries and LCD modules for this project. Make sure you've read the section on using libraries in Proteus software.
  • Let's begin by creating a new project, and importing all of the required components, and placing them within the working area.
  • Select all of the components from the Proteus component library that we'll require.

Circuit Diagram and Working:

After importing all required components to the workplace, let’s move to connecting them.

  • Starting with the connection of LEDs, we are using digital pins 2,3,4,5,6 for LEDs. Connect the positive side of the LEDs to the Arduino UNO board.
  • After that, connect the Ultrasonic sensor module’s Trig pin and Echo pin to digital pin 8 and 7 respectively, Vcc to 5v volt power and GND to Ground.
  • In the simulation. it will not be possible to change the distance from the Ultrasonic sensor so for that we have connected a potentiometer with the test pin of the module.
  • Now start the connection of the Keypad, as this is a 3x4 keypad so it will use 3 pins for columns and 4 pins for rows.
  • As there are limited digital pins on Arduino UNO, we have to use the analog pins of Arduino UNO as digital pins.
  • Now let’s connect the row pins A, B, C, D with A0, A1, A2, A3 respectively and column pins 1, 2, 3 with digital pins 9, 10, 11 respectively. And we have to connect the pins in an exact manner.
  • RTC module uses the I2C protocol, so we will connect SDA and SCL pins to Arduino UNO’s SDA (A4) and SCL (A5) pins respectively. Vcc with 5v power supply and Gnd with the ground.
  • As there are no pins left for connecting the LCD module therefore we will use an I2C GPIO expander for connecting the LCD module.
  • Connect the SDA and SCL pins of GPIO expander with the SDA and SCL pins of Arduino UNO and we have to set the slave address of GPIO expander, for that we will connect the A0, A1, A2 pins with ground, that will set the I2C slave address to 0x20.

Now we have done the circuit, it’s time to move to the coding side of this project.

Arduino code for the accident detection:

  • We must add relevant libraries, which operate as header files in programming languages before we begin writing the code.
  • So, if the necessary libraries aren't already installed in the Arduino IDE, we'll need to download them first.
  • We can install Arduino libraries by going to 'Sketch > Include Library > Manage Library' in the Arduino IDE. In the library manager, we can now search for our essential libraries. The libraries can also be installed via zip files.
  • We can download the libraries from the above instruction, but if they are not available, we can use the following links to download the zip files of libraries.
  • Here we used “Wire.h” to enable I2C communication and it is pre-installed.
  • “LiquidCrystal_I2C.h” is used for the LCD.
  • “Keypad.h” is used for the integration of the keypad module.
  • “RTClib.h” is the library for RTC modules.
  • Let’s declare the pins for modules. We mainly use two pins i.e. Trig and Echo for the object detection and distance calculation. Here we have connected the Echo pin to D7 and Trig pin to D8 in Arduino Uno and an array for storing the pins for LEDs as D2, D3, D4, D5, D6. Two arrays for storing the pins for keypads such as rowPins for A0, A1, A2, A3 pins and colPins for D9, D10, D11.
  • Now, Let’s declare configuration related variables for the keypad. Here we are declaring variables to store the number for Rows and Columns. We will use a 2D char array named ‘hexaKeys’ for storing the symbols of keypad.
  • Now declare some general variables for storing the values for ultrasonic sensors, charge, total charged amount, check-in time and check-out time of vehicles.
 
  • Now, Let’s declare the objects of the modules.
 
  • The “customkeypad” is initializing an instance of class NewKeypad. The statement is going to map these symbols with the pins we have declared to connect with Arduino. Hence, it will map according to the row and column pins.
  • Next, we are initializing the LCD display with an I2C serial interface and setting the address to 0x20 Hex.
  • And we are declaring an object named ‘rtc’ for the “RTC_DS1307” module.

Void Setup():

  • The void setup() is an important function in the sketch that will execute only once in the whole program. The input, output, and other serial communication initializations are done inside the void setup. Let’s write the void setup sketch now.
  • In this setup function, firstly we have enabled the serial communication with “Serial.begin” with the default baud rate of 9600.
  • Next, we are initializing the LCD and turning on the backlight of the LCD.
  • We have already declared the Trig and Echo pins before in the declaration part, and now we are going to set them up as output and input pins respectively.
  • There may be a doubt why we have declared a Trig as output and Echo as input. That is because the Trig pin will generate the ultrasonic wave pulses and the Echo pin will work as a receiver for reflected waves.
  • We are using five led’s for the five slots in the parking lot and to make the logic simpler, declare the led pins as output mode.
  • Now, we are printing a line in the serial monitor and LCD. We are using the cursor function and printing “Made by” in the first row and “Tushar Gupta” in the second row. (0,0) is representing (column, row) in the LCD.
  • After printing the line, clear the LCD screen.
  • Now, we are trying to initialize the RTC module and if the RTC is not found, it will print that “Couldn’t find RTC”. and halt the further processing of code.

  • After successful initialization of the RTC module we will know if the RTC module is running already , if yes then we don’t have to set the time explicitly otherwise we have to .
  • We will use a “dist()” function to calculate the distance using the formula mentioned in component details.
  • For the calculation of distance, we will generate the pulses using the Trig pin.
  • To generate the pulses , switch the TRIGpin to LOW for 4 microseconds and then HIGH for 10 microseconds then again LOW .
  • By using ‘pulseIn’ we can calculate the time duration the wave has taken to travel back from the object.
  • “ distance = duration*(0.034/2); ” and here 0.034 is the speed of sound and with this formula, we can calculate the distance in cm and set the threshold values.
  • “pulseIn” takes two arguments, first pin number and second logical state. This will read the pin for logic HIGH and return the time period in which that pin was at a HIGH state.
  • For more knowledge of “pulseIN “ refer to this link: pulseIN function

Void loop():

  • It is the next most important function of Arduino code/ sketch. The “void loop()” will run after the execution of “void setup()”.
  • We'll write the code required to run in a continuous loop in this part. So here we'll write our main application code.
  • Here, we are going to first discuss the Automatic billing part near the gate in our parking system.
  • In the loop function, the Date and Time of that current time are set by “rtc.now”, and the user will enter his slot number in the keypad when he/she is exiting from the slot.
  • The user will click the allocated slot number on the keypad and we are collecting that in the “customkey” variable using the “getkey” function.
  • The serial monitor will print the custom key entered by the user. Then we will check the slot status by “digitalRead (led[i])”.
  • If the led status is HIGH which means the slot was occupied now we will generate the bill for that slot and display that amount on the LCD display for1 second after clear the LCD and set that slot LED to LOW state.
  • The next step we are going to do is to calculate the total amount according to his vehicle staying inside the parking lot. And for that, we can do the simple calculation that is “amount = charge*(gotime [i] - cometime [i]) ;”.
  • We have already declared the charge amount in the above sections of the program. The charge will be multiplied by “go time - come time”, which is the total time the vehicle stayed inside the lot. And the multiplied result of stay time and charge is the final amount the driver has to pay for his parking slot.
  • Now, the driver can pay the amount and exit through the gate. Here, after a second delay, we are clearing the LCD display.
  • “What if the driver pressed any wrong key which has a free slot?” That might be the question in your mind. Well, we can cover that condition with an else statement, where we can print “The slot is already empty” on the LCD and let the driver know that he has entered the wrong key in the keypad near the exit gate.
  • Till now, we have seen the Automatic billing logic near the exit gate. But let’s see what is the slot allocation process at the entry gate.
  • As we have already calculated the distance with the ultrasonic sensor using the “dist()” function, we can set the distance limit to 100cm before the gate, and when a car reaches the entry gate the allocation of the slot will be started.
  • The “for loop” here will see what are the slots showing Low/empty in the parking and allocate that empty one to the car by printing “Park your car at ” and “Slot i” in the LCD.
  • As this slot was allocated, we have to write this LED as High which indicates the slot is not empty. This is the reason where the slot led is high at the exit gate when the user pressed his slot number in the keypad. We are turning on the LED when we are allocating the slot to a car.
  • Now we also have to collect the “come time” by the RTC module for further calculation at the end or near the exit gate.
  • We are implementing an if statement where the all LEDs are high, which means all the slots are filled, the LCD should print (“No more slots”) and inform the driver and clear the LCD screen.

Results / Working:

We have completed the Proteus simulation circuit and Arduino code for the Car Parking project. And it is ready for testing.

  • Before going to start the simulation, we have to add the hex file of our application code in the Arduino UNO module in Proteus and a hex code for the ultrasonic sensor also.
  • To add the hex file, click on the Arduino UNO and a new window will open then click on the Program files, there we will browse to our hex file.
  • In the same way, we can add a hex file for the ultrasonic sensor.
  • Now start the simulation, on the first boot of the circuit, LCD will display the welcome message and the same message will be displayed in the serial terminal also
  • Just for debugging purposes, we are continuously printing the ultrasonic sensor values.
  • In the simulation to change the distance between the vehicle and ultrasonic sensor we have used a potentiometer. Now change the value on the potentiometer.

As we can see that for 50% value on the pot ultrasonic sensor value is near to 500 cm and for 77% value on the pot ultrasonic sensor value is near to 850 cm.

  • Let's test the condition when the vehicle approaches the sensor, to satisfy that condition the object must be at a distance of less than 100 cm. For that, we have to change the pot value. Set the pot value near to 10 %.
  • After that LCD will display a message if that spot is vacant like “Park your car at Slot 1” and LED for the same location will glow.
  • To take the bill for any location press the keypad for that location number let’s suppose here the location is 1 so we will click on ‘1’
  • After that, it will generate the bill with the total charged amount and the LED for that location will be turned off.
  • In case if we click any slot button which is already vacant then LCD will display the message for the slot is vacant.

Here it is not visible which button on the keypad has clicked but suppose we have clicked ‘1’ and if that location is vacant then it will display that message.

  • Let’s take another case when we want to park another car. Now slot 1 is already busy so we will park at slot 2.
  • This time when the sensor value changes less than 100 cm, then the LCD display will show “Park your car at slot 2” because slot 1 is preoccupied.
  • In the image, we can see that both LEDs are glowing as both slots are occupied now.
  • For billing, we will click the button on the keypad for the respective slot.
  • Let’s take a case when all slots are occupied. Here we can see all slot LEDs are glowing.
  • Now we will try to park another car. Then LCD will display ‘no more slot’ as there is no vacant slot available at parking.

I hope you have a good understanding of how our Car parking system project works and that you have liked it. Although it’s a tough nut to crack in the first read, I strongly recommend you to read the logic part twice for better understanding. I believe we have covered almost everything, please let us know if you have any questions or suggestions in the comments section.

Thank you very much for reading this project. All the best for your projects!

Advantages of pursuing IPC certification in Electronics Assemblies & Inspection

In the highly competitive world of electronics, it has become obvious for leading companies to stick to the adhere standards of quality and consistency. Hence, many times companies and organizations prefer to adopt globally known standards to maintain singularity and high quality within the organization. Because IPC is considered the gold of all standards, many companies and organizations tend to follow it. For that very same reason, companies always prefer employees who demonstrate his/her ability to deliver as per IPC standards. It is vital to becoming an established professional in the field of electronics assembly and quality inspection to find a suitable job in the field of the electronics manufacturing industry. What could be the better way to showcase that other than proving your expertise in IPC certification? In other words, IPC certification helps you to put that stamp of quality in your resume.

Given that IPC has been globally adopted well-known standards for training in the field of electronics, many times you will find yourself working in an environment that adheres to IPC standards, where all professionals and organizations, you are working in communicates in IPC-based terminology. If you do not have a good handle on the IPC standard, it can cause unnecessary and expensive delays in the manufacturing process.

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Miscommunication among professionals due to non-standardized working processes can lead to inconsistency and expensive delayed production. In the OEM (original equipment manufacturers), CEMs (contract electronics manufacturers), ODMs (original design manufacturers) and EMS (electronics manufacturing service) industry, it is crucial that vendors and manufacturers/contractors use the same terminology and practice the same standards. IPC certification provides that certainty in the process. Many professionals associated with the electronics industry confirm all the advantages that come with IPC standardized practices within the industry due to cross-channel communication, and attribute their success, in large part, to speaking the same language.

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When a company consistently follows the IPC standardized production process and streamlines cross-channel communications and interactions, what comes next is a significant reduction in production costs and time.

IPC-A-610 course ensures the acceptability of electronic assemblies such as soldering criteria, surface mounting criteria and jumper wire assembly requirements among others, whereas and J-STD-001 course help maintains a standard of each product, at each stage in the assembly line and process, while evaluating and serving under the same scrutiny as others. On top of reducing costs by decreasing the number of rebuilds and reworks, these courses also focus on improving production time. These certifications establish standards within the fabrication process and guarantee that your operation employs a higher standard of quality control.

After pursuing IPC certifications, you’ll find yourself capable of delivering a consistent, high-quality product, and communicating with other vendors/manufacturers in your supply chain. These certifications enable your company to become a trusted provider within the industry as well as assure security in terms of future business growth.

If you currently do not have globally recognized IPC certification in your institute or on your resume and you want to make that superior change, contact Advanced Rework Technology (A.R.T.) today. A.R.T Ltd also offers bespoke training that can be based entirely around the requirements of your company and even specific products, with all theory and practical equipment supplied by them too. All is just a call away from you. Call A.R.T. Ltd today on 01245 237 083.

ESP32 Over The Air (OTA) Web Updater

Hello readers, I hope you are all doing great. In this tutorial, we are going to discuss the OTA web updater on the ESP32.

We already covered the fundamentals of OTA programming in ESP32, in our previous tutorial where we used the Arduino IDE to upload OTA code into the ESP32 module using the network port.

In the OTA web updater, you need to create a web server page for OTA programming.

[caption id="attachment_166886" align="aligncenter" width="1920"] ESP32 OTA web updater[/caption]

Fig.1 ESP32 OTA web updater

Where To Buy?
No.ComponentsDistributorLink To Buy
1ESP32AmazonBuy Now

Over the Air Web Updater

  • "Over-the-air" refers to the ability to wirelessly download an application, configuration, or firmware to internet-enabled devices, also known as IoT. (OTA). It functions similarly to our computers, laptops, tablets, and phones.
  • Instead of using a serial port and a wired medium to upload a code, the OTA web updater allows the user to update the code or firmware wirelessly via a web server.
  • When sensor nodes are frequently placed in remote or difficult-to-reach locations, OTA programming can be used.

Steps to implement an OTA web updater using ESP32

  • Using the serial communication port, upload the code containing the instructions to enable the OTA web updater (so that in the future you can update the code using a browser instead of a wired medium).
  • The code uploaded via the serial port will launch a web server, allowing you to upload new code over the air.
  • The new code, which has been uploaded using a web server, should contain instructions to keep the OTA web updater enabled on the ESP32 board so that you can use the OTA programming feature in future applications as well.
  • Create a .bin using Arduino IDE compiler and upload the file on the server.

Fig. 2

Code for OTA web updater implementation in ESP32

In this tutorial, we will discuss only the OTA web updater method using Arduino IDE and ESP32 dev-Kit V1 module.

If you want to know more about the basics of ESP32 and how to get started with Arduino IDE, then read Introduction to ESP32 Programming Series.

  • You can find the code through File> Examples> ArduinoOTA> BasicOTA.
  • An image has been attached below for reference:

Fig. 3

  • This code should be uploaded serially through a serial communication port only then you can access the OTA web updater feature.

Code

#include <WiFi.h> #include <WiFiClient.h> #include <WebServer.h> #include <ESPmDNS.h> #include <Update.h>   const char* host = "esp32"; const char* ssid = "SSID"; const char* password = "password";   WebServer server(80);   /* * Login page */   const char* loginIndex = "<form name='loginForm'>" "<table width='20%' bgcolor='A09F9F' align='center'>" "<tr>" "<td colspan=2>" "<center><font size=4><b>ESP32 Login Page</b></font></center>" "<br>" "</td>" "<br>" "<br>" "</tr>" "<td>Username:</td>" "<td><input type='text' size=25 name='userid'><br></td>" "</tr>" "<br>" "<br>" "<tr>" "<td>Password:</td>" "<td><input type='Password' size=25 name='pwd'><br></td>" "<br>" "<br>" "</tr>" "<tr>" "<td><input type='submit' onclick='check(this.form)' value='Login'></td>" "</tr>" "</table>" "</form>" "<script>" "function check(form)" "{" "if(form.userid.value=='admin' && form.pwd.value=='admin')" "{" "window.open('/serverIndex')" "}" "else" "{" " alert('Error Password or Username')/*displays error message*/" "}" "}" "</script>";   /* * Server Index Page */   const char* serverIndex = "<script src='https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js'></script>" "<form method='POST' action='#' enctype='multipart/form-data' id='upload_form'>" "<input type='file' name='update'>" "<input type='submit' value='Update'>" "</form>" "<div id='prg'>progress: 0%</div>" "<script>" "$('form').submit(function(e){" "e.preventDefault();" "var form = $('#upload_form')[0];" "var data = new FormData(form);" " $.ajax({" "url: '/update'," "type: 'POST'," "data: data," "contentType: false," "processData:false," "xhr: function() {" "var xhr = new window.XMLHttpRequest();" "xhr.upload.addEventListener('progress', function(evt) {" "if (evt.lengthComputable) {" "var per = evt.loaded / evt.total;" "$('#prg').html('progress: ' + Math.round(per*100) + '%');" "}" "}, false);" "return xhr;" "}," "success:function(d, s) {" "console.log('success!')" "}," "error: function (a, b, c) {" "}" "});" "});" "</script>";   /* * setup function */ void setup(void) { Serial.begin(115200);   // Connect to WiFi network WiFi.begin(ssid, password); Serial.println("");   // Wait for connection while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); } Serial.println(""); Serial.print("Connected to "); Serial.println(ssid); Serial.print("IP address: "); Serial.println(WiFi.localIP());   /*use mdns for host name resolution*/ if (!MDNS.begin(host)) { //http://esp32.local Serial.println("Error setting up MDNS responder!"); while (1) { delay(1000); } } Serial.println("mDNS responder started"); server.on("/", HTTP_GET, []() { server.sendHeader("Connection", "close"); server.send(200, "text/html", loginIndex); }); server.on("/serverIndex", HTTP_GET, []() { server.sendHeader("Connection", "close"); server.send(200, "text/html", serverIndex); });   /*handling uploading firmware file */ server.on("/update", HTTP_POST, []() { server.sendHeader("Connection", "close"); server.send(200, "text/plain", (Update.hasError()) ? "FAIL" : "OK"); ESP.restart(); }, []() { HTTPUpload& upload = server.upload(); if (upload.status == UPLOAD_FILE_START) { Serial.printf("Update: %s\n", upload.filename.c_str()); if (!Update.begin(UPDATE_SIZE_UNKNOWN)) { //start with max available size Update.printError(Serial); } } else if (upload.status == UPLOAD_FILE_WRITE) { /* flashing firmware to ESP*/ if (Update.write(upload.buf, upload.currentSize) != upload.currentSize) { Update.printError(Serial); } } else if (upload.status == UPLOAD_FILE_END) { if (Update.end(true)) { //true to set the size to the current progress Serial.printf("Update Success: %u\nRebooting...\n", upload.totalSize); } else { Update.printError(Serial); } } }); server.begin(); }   void loop(void) { server.handleClient(); delay(1); }

Code Description

The first task is to add the header files, required to perform over the air (OTA) web updates using the ESP32 module.
  • WiFi.h : This header file allows the ESP32 board to connect to the internet. It can serve either as a server or a client.
  • ESPmDNS.h : This library is used to implement multicast DNS query support for the ESP32 chip. A multicast UDP service is used to provide local network service.
  • WiFiClient.h : It is used to create a client that can connect to a specific port and IP address.

Fig. 4

  • Enter the SSID and password.

Fig. 5

  • You can style the HTML page anytime as per your requirements or use the default style given in the example code.

Setup()

  • Initialize the serial monitor at a 115200 baud rate.
  • WiFi.begin() function is used to initialize the Wi-Fi module with Wi-Fi credentials used as arguments.

Fig. 6

  • Wait until the ESP32 is connected to the Wi-Fi network.

Fig. 7

  • If the device is connected to a local Wi-Fi network then print the details on the serial monitor.
  • WiFi.localIP() function is used to fetch the IP address.
  • Print the IP address on the serial monitor using Serial.println() function.

Fig. 8

  • Use multicast Domain Name System (mDNS) for hostname resolution.
  • Hostname has been defined as a global variable at the beginning of code.
  • Start the mDNS responder for esp32 or host using MDNS.begin() function.

Fig. 9

  • Return the index page which is stored in serverIndex.
  • Send the status OK (200 represents ‘OK’) to inform the client.

Fig. 10

  • Handling the uploading of firmware files.

Fig. 11

  • Start uploading the new firmware into the ESP32 board.

Fig. 12

  • Server.begin() function will start the server to listen for incoming connections.

Fig. 13

Loop()

  • Server.handleCLient() function is used to handle the client devices.
  • It will monitor the client devices and provide the requested HTML page.

Fig. 14

  • After successfully uploading the code into ESP32 board using serial communication port, open the serial monitor with 115200 baud rate.
  • Press EN or enable button from the ESP32 board.
  • You can see the IP address printed on the serial monitor, once the ESP32’s Wi-Fi module is connected to wi-fi network.
  • We have attached a screenshot below for your reference:

Fig. 15 Serial monitor

Testing

  • Now the ESP32 module is ready for over the air (OTA) programming.
  • For testing the OTA web updater, remove the ESP32 module from your computer and power the ESP32 board using another power source.
  • Open the browser and enter the IP address from the Serial Monitor as shown in the above image.
  • A web page with an IP address of 168.43.223 is shown below:

Fig. 16

  • Enter the username and password on the login page. As per the example code:
Username: admin Password: admin
  • You can change the username and password details if you wish to.
  • Click on Login.
  • A new browser page with URL 192.168.43.223/serverIndex will be displayed on the screen, as shown below:

Fig. 17

  • You can style the browser page as per your requirements.

Test code

  • Write a new code in Arduino IDE.
  • The code should contain two sections:
  1. The instructions to keep OTA web updater feature enabled
  2. Instructions to blink the LED (you can replace the LED code with another code as per your requirements).
#include <WiFi.h> #include <WiFiClient.h> #include <WebServer.h> #include <ESPmDNS.h> #include <Update.h>   const char* host = "esp32"; const char* ssid = "SSID"; const char* password = "password";   //variabls to blink without delay: const int led = 2; unsigned long previousMillis = 0; // will store last time LED was updated const long interval = 1000; // interval at which to blink (milliseconds) int ledState = LOW; // ledState used to set the LED   WebServer server(80);   /* * Login page */   const char* loginIndex = "<form name='loginForm'>" "<table width='20%' bgcolor='A09F9F' align='center'>" "<tr>" "<td colspan=2>" "<center><font size=4><b>ESP32 Login Page</b></font></center>" "<br>" "</td>" "<br>" "<br>" "</tr>" "<td>Username:</td>" "<td><input type='text' size=25 name='userid'><br></td>" "</tr>" "<br>" "<br>" "<tr>" "<td>Password:</td>" "<td><input type='Password' size=25 name='pwd'><br></td>" "<br>" "<br>" "</tr>" "<tr>" "<td><input type='submit' onclick='check(this.form)' value='Login'></td>" "</tr>" "</table>" "</form>" "<script>" "function check(form)" "{" "if(form.userid.value=='admin' && form.pwd.value=='admin')" "{" "window.open('/serverIndex')" "}" "else" "{" " alert('Error Password or Username')/*displays error message*/" "}" "}" "</script>";   /* * Server Index Page */   const char* serverIndex = "<script src='https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js'></script>" "<form method='POST' action='#' enctype='multipart/form-data' id='upload_form'>" "<input type='file' name='update'>" "<input type='submit' value='Update'>" "</form>" "<div id='prg'>progress: 0%</div>" "<script>" "$('form').submit(function(e){" "e.preventDefault();" "var form = $('#upload_form')[0];" "var data = new FormData(form);" " $.ajax({" "url: '/update'," "type: 'POST'," "data: data," "contentType: false," "processData:false," "xhr: function() {" "var xhr = new window.XMLHttpRequest();" "xhr.upload.addEventListener('progress', function(evt) {" "if (evt.lengthComputable) {" "var per = evt.loaded / evt.total;" "$('#prg').html('progress: ' + Math.round(per*100) + '%');" "}" "}, false);" "return xhr;" "}," "success:function(d, s) {" "console.log('success!')" "}," "error: function (a, b, c) {" "}" "});" "});" "</script>";   /* * setup function */ void setup(void) { pinMode(led, OUTPUT);   Serial.begin(115200);   // Connect to WiFi network WiFi.begin(ssid, password); Serial.println("");   // Wait for connection while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); } Serial.println(""); Serial.print("Connected to "); Serial.println(ssid); Serial.print("IP address: "); Serial.println(WiFi.localIP());   /*use mdns for host name resolution*/ if (!MDNS.begin(host)) { //http://esp32.local Serial.println("Error setting up MDNS responder!"); while (1) { delay(1000); } } Serial.println("mDNS responder started"); /*return index page which is stored in serverIndex */ server.on("/", HTTP_GET, []() { server.sendHeader("Connection", "close"); server.send(200, "text/html", loginIndex); }); server.on("/serverIndex", HTTP_GET, []() { server.sendHeader("Connection", "close"); server.send(200, "text/html", serverIndex); }); /*handling uploading firmware file */ server.on("/update", HTTP_POST, []() { server.sendHeader("Connection", "close"); server.send(200, "text/plain", (Update.hasError()) ? "FAIL" : "OK"); ESP.restart(); }, []() { HTTPUpload& upload = server.upload(); if (upload.status == UPLOAD_FILE_START) { Serial.printf("Update: %s\n", upload.filename.c_str()); if (!Update.begin(UPDATE_SIZE_UNKNOWN)) { //start with max available size Update.printError(Serial); } } else if (upload.status == UPLOAD_FILE_WRITE) { /* flashing firmware to ESP*/ if (Update.write(upload.buf, upload.currentSize) != upload.currentSize) { Update.printError(Serial); } } else if (upload.status == UPLOAD_FILE_END) { if (Update.end(true)) { //true to set the size to the current progress Serial.printf("Update Success: %u\nRebooting...\n", upload.totalSize); } else { Update.printError(Serial); } } }); server.begin(); }   void loop(void) { server.handleClient(); delay(1);   //loop to blink without delay unsigned long currentMillis = millis();   if (currentMillis - previousMillis >= interval) { // save the last time you blinked the LED previousMillis = currentMillis;   // if the LED is off turn it on and vice-versa: ledState = not(ledState);   // set the LED with the ledState of the variable: digitalWrite(led, ledState); } }

Test Code Description

  • We are using the same old code with an additional LED blinking part.
  • In this code, we are using inbuilt LED for testing.
  • Define the GPIO pin to which LED is connected.
  • GPIO 2 is connected to the inbuilt LED.
  • To add delay, we are using timers instead of delay() function.
  • The variable interval is defining the time delay.
  • Set LED’s state to low.

Fig. 18

Arduino Loop() Function

  • Blink the LED after every 1000ms or 1sec delay as defined in variable ‘interval’.

Fig. 19

How to generate a bin file

  • Compile the code in Arduino IDE.
  • Go to Sketch > Export compiled Binary or press Crl+Alt+S to generate .bin file.

Fig. 20

Fig. 21 bin file

  • Upload the .bin file on the browser with 192.168.43.223/serverIndex URL and click on update option.
  • At 100% progress the inbuilt LED from the ESP32 board will start blinking.

Fig 22

Fig. 23 LED blink

  • Similarly, you can upload a new code using over the air web updater.

This concludes the tutorial. I hope, you found this helpful and I hope to see you soon for the new ESP32 tutorial.

PWM with STM32

PWM stands for Pulse-Width Modulation. Once the switching frequency (fsw) has been chosen, the ratio between the switch-on time (TON) and the switch-off time (TOFF) is varied. This is commonly called duty-cycle (D). The duty cycle can be between 0 and 1 and is generally expressed as a percentage (%).

D = TON / (TON + TOFF) = TON x fsw

The variation of the pulse width, made at a high frequency (kHz), is perceived as continuous and can be translated into a variation of the rotation speed of a motor, dimming a LED, driving an encoder, driving power conversion, and etc. The use of PWM is also widely used in the automotive sector in electronic control units (ECU - Electronic Control Unit) to manage the energy to be supplied to some actuators, both fixed and variable frequency. Among the various actuators used in a vehicle and controlled by PWM i.e. diesel pressure regulator, EGR valve actuator, voltage regulator in modern alternators, turbocharger variable geometry regulation actuator, electric fans, etc.

Where To Buy?
No.ComponentsDistributorLink To Buy
1STM32 NucleoAmazonBuy Now

PWM signal generation through Timer in STM32

Let's see now how it is possible to generate a PWM with STM32. In this case, it can be generated using a timer made available by the microcontroller.

STM32 configuration with STCube

In this article, we will see how to configure and write an application to dim an LED connected to an output pin (GPIO) of the STM32F446RE Nucleo board. First of all, let's see how to configure the initialization code with the STCube tool.

Basic Configurations

GPIO selection and configuration

It is necessary to identify a GPIO to associate a timer to generate the PWM. For example, we choose PB3 associated with Channel 2 of Timer 2 (TIM2_CH2). Note that the pin turns orange to remind us of that timer 2 still needs to be configured.

System Reset and Clock Control (RCC) Initialization

  • To initialize the RCC use the following path: “Pinout & Configuration”-> System Core -> RCC. “High-Speed Clock” (HSE) and “Low-Speed Clock” (LSE) select for both “Crystal/Ceramic Resonators”.

Timer 2 Configuration

Now you need to configure timer two which is hooked to pin PB3.

Clock Configuration

We configure the clock tree so that the clock frequency (HCLK) of the microcontroller is 84 MHz, handling frequency divisor and multiplier of PLLCLK. The bus to which the timers are connected (APB1 timer and APB2 timer clocks) is also at 84 MHz.

Timer Configuration

We now know that timer 2 has a clock source of 84 MHz, so every time the clock switches the timer does a count. If we configure it to count to 84 million (it is a 32-bit timer, the Counter must be between 0 and 4294967295) it will take a second. We can set this number to exactly half so that the LED lights up for half a second and turns it off for another half-second. In practice, we will see at the output a square wave that will have a duty cycle of 50% and a switching frequency of 1Hz (too slow not to notice the switching on and off the LED !!). To do what has been said, the timer must be configured as follows:

  1. Enable PWM Generation on Channel 2;
  1. Set Prescaler to 0
  2. Set Counter Mode to “Up”;
  3. Set Counter Period to 83999999;
  4. Set Internal Clock Division to “No Division”;
  5. Set auto-reload preload to “Disable”;
  6. Set Master-Slave Mode to “Disable”;
  7. Set Trigger Event Selection to “Reset (UG bit from TIMx_EGR”;
  8. Set Mode to “PWM mode 1”;
  9. Set Pulse to 0;
  10. Set Output compare preload to “Enable”;
  11. Set Fast Mode to “Disable”
  12. Set CH Polarity to “High”.

Now we are ready to lunch the initialization code and write our application.

The initialization code

In “Private variables” we find TIM_HandleTypeDef htim2, it is an instance to C struct that needs to manipulate the DAC peripheral. In “Private function prototypes” the function prototype used to initialize and configure the peripherals:
/* Private function prototypes -----------------------------------------------*/ void SystemClock_Config(void); static void MX_GPIO_Init(void); static void MX_TIM2_Init(void);/* USER CODE BEGIN PFP */
At the end of main() we find the initialization code of System Clock, Timer 2 and GPIO ( as previously selected in STCube):
void SystemClock_Config(void) { RCC_OscInitTypeDef RCC_OscInitStruct = {0}; RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};   /** Configure the main internal regulator output voltage */ __HAL_RCC_PWR_CLK_ENABLE(); __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3); /** Initializes the RCC Oscillators according to the specified parameters * in the RCC_OscInitTypeDef structure. */ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI; RCC_OscInitStruct.HSIState = RCC_HSI_ON; RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT; RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON; RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI; RCC_OscInitStruct.PLL.PLLM = 16; RCC_OscInitStruct.PLL.PLLN = 336; RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV4; RCC_OscInitStruct.PLL.PLLQ = 2; RCC_OscInitStruct.PLL.PLLR = 2; if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) { Error_Handler(); } /** Initializes the CPU, AHB and APB buses clocks */ RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2; RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK; RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2; RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;   if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK) { Error_Handler(); } }   /** * @brief TIM2 Initialization Function * @param None * @retval None */ static void MX_TIM2_Init(void) {   /* USER CODE BEGIN TIM2_Init 0 */   /* USER CODE END TIM2_Init 0 */   TIM_MasterConfigTypeDef sMasterConfig = {0}; TIM_OC_InitTypeDef sConfigOC = {0};   /* USER CODE BEGIN TIM2_Init 1 */   /* USER CODE END TIM2_Init 1 */ htim2.Instance = TIM2; htim2.Init.Prescaler = 0; htim2.Init.CounterMode = TIM_COUNTERMODE_UP; htim2.Init.Period = 83999999; htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1; htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE; if (HAL_TIM_PWM_Init(&htim2) != HAL_OK) { Error_Handler(); } sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET; sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE; if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK) { Error_Handler(); } sConfigOC.OCMode = TIM_OCMODE_PWM1; sConfigOC.Pulse = 0; sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH; sConfigOC.OCFastMode = TIM_OCFAST_DISABLE; if (HAL_TIM_PWM_ConfigChannel(&htim2, &sConfigOC, TIM_CHANNEL_2) != HAL_OK) { Error_Handler(); } /* USER CODE BEGIN TIM2_Init 2 */   /* USER CODE END TIM2_Init 2 */ HAL_TIM_MspPostInit(&htim2);   }   /** * @brief GPIO Initialization Function * @param None * @retval None */ static void MX_GPIO_Init(void) {   /* GPIO Ports Clock Enable */ __HAL_RCC_GPIOB_CLK_ENABLE();   }   /* USER CODE BEGIN 4 */   /* USER CODE END 4 */   /** * @brief This function is executed in case of error occurrence. * @retval None */ void Error_Handler(void) { /* USER CODE BEGIN Error_Handler_Debug */ /* User can add his own implementation to report the HAL error return state */ __disable_irq(); while (1) { } /* USER CODE END Error_Handler_Debug */ }

On/Off LED with STM32

Now we are ready to write our code in main() to on/off LED.
int main(void) { /* USER CODE BEGIN 1 */ /* USER CODE END 1 */ /* MCU Configuration--------------------------------------------------------*/ /* Reset of all peripherals, Initializes the Flash interface and the Systick. */ HAL_Init(); /* USER CODE BEGIN Init */ /* USER CODE END Init */ /* Configure the system clock */ SystemClock_Config(); /* USER CODE BEGIN SysInit */ /* USER CODE END SysInit */ /* Initialize all configured peripherals */ MX_GPIO_Init(); MX_TIM2_Init(); /* USER CODE BEGIN 2 */ HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_2); __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_2, 41999999); /* USER CODE END 2 */ /* Infinite loop */ /* USER CODE BEGIN WHILE */ while (1) { /* USER CODE END WHILE */ /* USER CODE BEGIN 3 */ } /* USER CODE END 3 */ }

As mentioned earlier we have set the timer two to count up to 84 million, so we know that counting 84 million a second has elapsed. Now let's use the PWM function to make sure that for half a second the LED stays on and the other half a second off. In practice, to generate a square wave with a duty cycle of 50% and a frequency of one second.

We use the function “HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_2)” to enable timer 2 to start in PWM mode and the macro “__HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_2, 41999999)” tells the timer which is the value with which to compare the internal count (in this case 41999999) to decide whether the LED should be off or on.

Now we just must connect a led between pin PB3 and ground through a 220OHm resistor to limit the current (if we want to work with a duty cycle of 100%) and compile our application.

Once this is done, we see that the LED will remain on for 500ms second and off for another 500ms as can be seen from the waveform acquired by the PB3.

Since we have chosen a switching frequency of the PWM that is too low (1Hz), we will only see the LED turn on and off and we do not check its luminosity: we will see in the next paragraph how to increase the switching frequency, adjust the duty cycle in order to increase and decrease the brightness.

Dimming LED using PWM in STM32

First, we declare the following define:

#define D_COUNTER 839

Now, we associate it with the field “htim2.Init.Period” of the structure *htim2:

htim2.Init.Period = D_COUNTER;

In this way, we can quickly the number of counts that the timer must do and therefore manage the frequency and duty cycle of our PWM.

This way our timer will count up to 839 in 10us. Consequently, the switching frequency will be 100kHz (clearly exceeding 1Hz !!). Note that as in the previous example we have subtracted 1 from the count value because the timer starts at zero.

Then, we define an unsigned int variable to set the duty cycle:

unsigned int D; //duty cycle In the main() we write; /* USER CODE BEGIN 2 */ D= 10; //it menas duty cycle of 10% HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_2); __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_2, (D_COUNTER/100)*D); /* USER CODE END 2 */

Where (D_COUNTER/100)*D needs to re-proportion the value of the duty cycle to the count that the timer must perform.

Compiling we will see that now the LED will always be on but with low brightness, in fact, the duty cycle is only 10% as can be seen from the generated waveform and the rms value of the voltage given to the LED is about 1.1 Volt (as you can see in the bottom corner of the RMS figure for the green trace). Furthermore, the figure confirms that the duty cycle is 10% both intuitively by looking at the green trace and by reading the measurement at the bottom center (Dty+ = 10,48%).

If we set D=70, the LED will be brighter, in fact the RMS value is about 2.82 Volt (as you can see in the bottom corner of the RMS figure for the green trace). Furthermore, the figure confirms that the duty cycle is 70% both intuitively by looking at the green trace and by reading the measurement at the bottom center (Dty+ = 69,54%).

If we set D=100, the led will be illuminated with the maximum brightness imposed by the limitation of the 220 Ohm resistor. The rms value at the ends of the LED with the resistance in series will be 3.3 Volts (the maximum generated by the GPIO)

Now if you write the following code on while(), we will see that the LED will change brightness every 100ms (in practice it increases, every 100ms the duty by 1% starting from 1% until it reaches 100% and then starts all over again)

/* Infinite loop */ /* USER CODE BEGIN WHILE */ while (1) { /* USER CODE END WHILE */ for(D=1; D<=100; D++){ HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_2); __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_2, (D_COUNTER/100)*D); HAL_Delay(100); } /* USER CODE BEGIN 3 */ } /* USER CODE END 3 */

To do this we include the PWM configuration function ( HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_2); __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_2, (D_COUNTER/100)*Duty) in the following loop for(D=1; D<=100; D++) which increases the value of variable D by 1 every 100 ms through the function HAL_Delay(100).

Now we are ready to effectively manage the PWM to control the brightness of a led, but in a similar way, we can control the speed of a DC motor or various actuators.

Working Principle of HVAC System

Hi readers! I hope you are doing well and want to learn something new. Have you ever asked why our homes feel warmer when it’s cold and cooler when it’s hot out? Welcome to learn some of the secrets of HVAC Systems. Today, we will learn about the HVAC System.

Specific requirements of HVAC refer to all installations providing comfort as well as keeping a good air condition indoors for residential, commercial, and industrial buildings. It discusses the necessary components for comfortable air in your home: temperature, humidity, and cleanliness through heating, cooling, and fresh air. Most HVAC systems are based on thermodynamic principles and operate using the refrigeration cycle to transport heat through the phases of heat transfer by compressing, condensing, expanding, and evaporating refrigerants. 

Heating the entire or a small part of your house is done by adding thermal energy from a furnace, boiler, or heat pump. Evacuation of heat from within to an external environment using an evaporator and condenser coil installed with a compressor and expansion valve is done by collecting up indoor heat and then releasing that heat outside. Both natural and mechanical-focused ventilation bring fresh air from outside while at the same time eliminating carbon dioxide, moisture, and pollutants from within.

The modern HVAC system has it all, which ranges from split systems and ductless mini-splits to packaged units and geothermal systems. Control usually encompasses thermostats, and most of the time, those are attached to building management systems for higher efficiency. Energy efficiency can be termed as those measures taken to minimize the wastage of energy, and it is expressed in SEER, EER, or COP metrics.

Energy efficiency is important and expressed in metrics such as SEER, EER, and COP. As smart technology and the green agenda continue to gain acceptance, HVAC keeps on evolving with better automation, green refrigerants, and more adaptive controls for comfort and lesser energy consumption.

In this article, we will find a detailed guide on the working principle of the HVAC System. Let’s dive.

What is an HVAC System?

HVAC stands for "heating, ventilation, and air conditioning" both in whole and the technology of regulating an indoor climate condition (air quality and comfort) in indoor structures. Heating raises an indoor ambient temperature during the winter months by creating and distributing heat in the form of various modes of heating. Devices used are furnaces, heat pumps, and boilers.

Ventilation improves indoor air quality differently. Ventilation replaces indoor air with new, fresher air from outside while also exhausting indoor pollutants, moisture, and odors. Air conditioning cools indoor air after humidity and excess heat are removed. Collectively, HVAC systems are designed to deliver and maintain an indoor environment that is healthy, comfortable, and energy efficient, and where people can be productive and healthy, does not what the outdoor climate is like.

So, with these elements, it’s possible to secure, make comfortable, and make energy-efficient indoor areas, regardless of what happens outside. By using these systems, people indoors can maintain their health, achieve good results at work, and manage their local climate. 

Core Components of an HVAC System:

Components 

Brief Description

Thermostat

Monitors indoor temperature and signals HVAC components to heat or cool. Smart models improve efficiency through scheduling and automation.

Furnace/Boiler

Using gas, oil, or electricity, it warms either air in a furnace or water in a boiler. Used mainly to keep homes warm in colder areas.

Heat Exchanger

Moves the warmth from combustion gases or electric coils either directly to air or to circulating water, separate from indoor air..

Evaporator Coil

Uses indoor heat to cool air during the summer. Refrigerant inside the coil soaks out heat and ensures the air in your home becomes cooler.

Condenser Coil

Placed outside, it sends off the heat captured from inside to the environment, transforming the refrigerant into a liquid.

Compressor

Forces and moves the refrigerant from the evaporator to the condenser through the system. Important for the function of a refrigeration cycle.

Blower Fan

Pushes air over the evaporator or heat exchanger and distributes conditioned air through ducts into rooms.

Air Filter

Takes dust, allergens, and extra particles out of the air. Maintains a clean indoor environment and preserves the important parts of your heating and cooling system.

Ductwork

A network of insulated pipes or channels that distribute heated or cooled air throughout the building and return it for reconditioning.

Vents & Registers

Openings in walls, floors, or ceilings where air enters or exits rooms. Registers often have adjustable grilles for airflow control.

Working Principle:

1. The Thermodynamic Cycle:

The refrigerator cycle is the foundation of all HVAC air conditioning systems. The refrigeration cycle is a natural process based on the concept of heat flow from a higher temperature site to a lower temperature site. But by putting energy into this process, we can move heat from a lower temperature site to a higher temperature site. Thermodynamically, the HVAC concept allows us to move heat from the indoor space to the outdoor air, cooling the occupied space.

Compressor:

Once the refrigerant gas has absorbed heat and changed to a gas at the evaporator coil, it will then be sent to the compressor, located in the outdoor unit or the compressor/condenser unit. The compressor produces both pressure and temperature by being compressed into a smaller space. The high-pressure-high-temperature gas then leaves the compressor and heads to the outdoor condenser coil.

Condensation:

In the condenser coil (generally also located outside the building), that hot refrigerant gives off heat to the outside air and begins to condense back to a liquid. The refrigerant, however, will still be under a high-pressure condition.

Expansion:

This high-pressure liquid refrigerant then passes through an expansion valve or a capillary tube. This will lower its pressure as well as its temperature all at once. The refrigerant is now a cold, low-pressure liquid and will then go through the phase of cooling.

This cycle continues incessantly, factoring in the conditioned environment and staying with a comfortable temperature profile. The significance is that with heat pumps, this process can be turned upside down to deliver heating and cooling according to seasonality. 

2. Heating Methods of HVAC Systems:

HVAC systems can utilize various methods for heating indoor spaces. Each of the methods may serve particular building sizes, climates, and types of energy sources. Below are the most commonly used heating systems: 

Furnaces:

Furnaces are a popular heating method throughout much of North America. They send hot air through ducts that deliver it to all areas in the building. A variety of fuels can be used to run a furnace. 

  • Natural gas is burned in the heat exchanger of a gas furnace to heat the air. 

  • With an electric furnace, heat is generated by electricity through coil filaments. Electric resistance heating is typically preferred when electricity costs are low or when gas is not available. 

  • Oil Furnace: Seldom found today, but may be used in some older homes or rural applications. 

Furnaces can heat quickly and can also be incorporated with a central AC system to control the climate throughout the year.

Heat Pumps: 

Similar to air conditioning, heat pumps work by taking heat from outside to inside in the winter and, in summer, pushing heat from inside to out.

  • In heating mode, heat pumps take heat from outside, even while it's cold outside, and use it to heat a space inside. 

  • While cooling, the system changes the direction it moves cool air from the outside to the inside (just like a normal air conditioner).

An air-source pump is what is classified as an "A" type source heat pump. Ground-source heat pumps or geothermal heat pumps take heat energy from under the earth, so less energy is used.

Under moderate climate conditions, heat pumps provide plenty of usefulness. Used properly, based on your climate and season, we saw some energy bills reduced by up to 50 percent.

Boilers and Radiant Heating: 

Heating with a boiler is common in older homes that don’t have ductwork. A boiler transforms water into heat, which it shares through a network of pipes (or radiators or a radiant system) to heat the space.

  • Radiant floor heating will give you consistent warmth, better efficiency of your existing heating system, and a reduced amount of energy consumed. 

  • A boiler run on either natural gas, oil, or electricity is the primary source that acts as the heart of a radiant floor heating system. An efficiently maintained boiler can reliably run for 20 - 30 years. 

3. Principles of Ventilation:

Fresh, healthy, and comfortable indoor air is made possible mostly by the ventilation function of HVAC. If the air becomes saturated and polluted inside homes, ventilation can stop this from causing discomfort and harming people’s health.

Why is ventilation important?

Constant air change must improve indoor air quality by continuously replacing stale indoor air with fresh outdoor air. Constant ventilation will also help in eliminating excess moisture. Excessive moisture creates a conducive environment for the growth of mold, mildew, and contributes to unpleasant odors from the chef, pets, home products, or cleaning products.

Every minute of every day, a little carbon dioxide (CO₂) is released. CO₂ stays trapped inside a closed room and can create a lot of trouble, due to its properties as a greenhouse gas, if there is no airflow. Others give off volatile organic compounds (VOCs); some home cleaning products, some paints, some furniture, etc. To have a VOC issue in any location takes a pretty high concentration. It moves some of the air around the home, ventilating and keeping oxygen up, while decreasing humidity, creating a healthier and better-feeling living space.

Types of Ventilation:

Type 

Description 

Natural Ventilation

Uses windows, vents, and openings to allow outdoor air to flow in freely.

Mechanical Ventilation

Uses fans and ducts to remove stale air and introduce fresh air.

Balanced Ventilation

A system that brings in fresh air while simultaneously exhausting stale air.

Heat Recovery Ventilators (HRVs)

Exchange heat between incoming and outgoing air streams to improve efficiency.

Energy Recovery Ventilators (ERVs)

Transfer both heat and moisture, helping to maintain indoor humidity balance.

4. Air Conditioning: Cooling Cycle

To achieve air conditioning, heat and moisture from the indoor air are removed.

Cooling Cycle:

  • The evaporator (indoor coil) absorbs heat from the indoor air

  • The compressor sends refrigerant outside to remove heat

  • The condenser (outdoor coil) rejects heat to the outside air

  • Expansion Valve (for this discussion only) cools the refrigerant before it goes back through the cycle

The cooling cycle lowers both temperature and humidity inside a building, designed to achieve a comfortable environment.

5. Controls and Automation:

HVAC systems utilize various sensors and control mechanisms to achieve optimal operation. 

Thermostats: 

  • Control the temperature set point

  • Modern thermostats are programmable and Wi-Fi enabled

Zoning Systems:

Segment building into multiple zones, allowing for independent temperature control

Building Management Systems (BMS):

Monitor or control large HVAC systems with centralized software.

Energy Efficient HVAC Systems:

  • Choose Energy-Efficient Equipment: When selecting HVAC equipment, look for Energy Star-rated equipment, which has been shown to use less energy.

  • Seal Ducts and Pipe Insulation: There are layers of efficiency that are lost to the outside; maximize duct-system component efficiency.

  • Install Programmable Thermostats: Using a programmable thermostat allows your team to select the temperature that will automatically adjust depending on the occupancy or schedule.

  • Install Variable Speed Components: Variable speed motors, for both the compressor and fan(s), sense system demand, and you can save significant energy costs.

  • Schedule Clean and Check Equipment: Ensure air filters are clean, refrigerant charge is correct, and connect with the HVAC vendor for regular maintenance.

  • Size and Optimize: Be sure to size and layout equipment correctly to achieve the best efficiency.

  • Replace Old Equipment: There is a general rule in energy efficiency that says if the old equipment is not cost-effective to maintain, it is better to replace new energy-efficient systems.

Performance Metrics:

Metric

Description

SEER (Seasonal Energy Efficiency Ratio)

Cooling efficiency over a season. Higher SEER = better.

EER (Energy Efficiency Ratio)

Instantaneous cooling efficiency.

AFUE (Annual Fuel Utilization Efficiency)

Efficiency of heating systems. Higher AFUE = less wasted fuel.

COP (Coefficient of Performance)

Ratio of heating/cooling provided to energy consumed.

Conclusion:

These systems assist in providing healthy air indoors, along with comfort levels for temperature, humidity, and air quality for persons in that space. Such systems can therefore be used almost anywhere to keep people comfortable, safe, and productive throughout the year. If people know about the HVAC cycle, ventilation, and heating, they are better prepared to decide what to do with their system.

On account of rising energy prices and more awareness of climate problems, there is now more attention on energy-saving HVAC technology. Today, most heating and cooling systems feature smart thermostats, adjustable-speed parts, and mild-to-the-environment refrigerants. Frequent maintenance and using advanced strategies for control can considerably increase the system’s productivity and its useful lifespan.

With time, the HVAC industry will seek smarter and more sustainable ways to achieve a balance between results and environmental protection. By being informed about advancements, individuals can enjoy better comfort, lessen their energy dependence, and lessen the harm HVAC systems may have on the environment.

Simple 4-Way Traffic Light Control using Arduino

Hello friends, I hope you’re all well and healthy. In today’s tutorial, we will be going through a simple, yet effective practice to design a 4-way traffic light simulation in Proteus software. This project is designed for undergrad engineering students with majors in electronics, electrical and mechatronics engineering. It is also useful for people that want to learn the basics of circuit design and Arduino programming.

Where To Buy?
No.ComponentsDistributorLink To Buy
1LEDsAmazonBuy Now
2Arduino Mega 2560AmazonBuy Now

4-Way Traffic Light Control using Arduino:

Traffic lights are an integral part of the world’s transportation systems. Over the years a number of different algorithms regarding traffic lights have been developed. The algorithm being used at any place for the purpose of controlling traffic takes into account of various factors, such as number of lanes, people that cross a certain road, etc. The most common usage of traffic lights is to control the flow of traffic, which means providing a steady flow for people to go about their daily business on the road. Traffic lights help reduce accidents by a large margin since they allow the flow of vehicles in only one direction at a time. Traffic lights also help in avoiding traffic jams. The most common traffic light pattern being used in the world today is a 4-way traffic control that accounts for pedestrians as well. This sort of pattern is used in main city blocks and squares since these possess both vehicular traffic as well as pedestrian traffic. Traffic lights have a universal color understanding that red light signals for the traffic to stop, yellow light serves as a transition light from going to stop and vice versa.

Software to Install:

Since we are simulating this project instead of designing it using hardware components, you need to fill some requisites so that you can follow our procedure. At first, we need to have the simulating software. For simulation purposes, we will use the Proteus software, if you already have that installed, that is excellent. However, if you don’t, you should Install Proteus Software. Proteus is a circuit simulating software that has an open database that can be customized quite easily, leaving room to add new components along with their libraries. To start working with Proteus for this project, you need to add the following libraries:

  • Arduino Library for Proteus: This library includes all the Arduino boards, giving you options to simulate your circuit exactly according to your needs.

Project Overview:

The main components of a 4-way traffic light are:

  • Arduino Mega: For this circuit, we recommend using Arduino mega, that is because to control 4-way traffic along with pedestrian lights, we need 20 output pins while an Arduino UNO only has 14 digital I/O pins.
  • Traffic light module: This is an inbuilt traffic light module you can find in Proteus, there is no need for any additional libraries for this.
  • Pedestrian Lights: To distinguish pedestrian lights, we will use simple LEDs.

In this certain design, we have used delays to control the ON and OFF time of the traffic lights. There are other ways around this as well but using delays with Arduino is the simplest and most effective way for small projects.

The pedestrian lights are set up so that whenever a certain traffic light is GREEN, its opposing pedestrian light on which there is no traffic is turned ON and signals for the pedestrians to walk.

Components Needed:

  • Arduino Mega
  • Green and Red LEDs
  • Traffic Lights

Component details:

Arduino Mega:

Arduino Mega is a programmable microcontroller board.

Arduino Mega contains ATMegaGA2560 and is based on that microcontroller.

Every Arduino board is equipped with voltage regulators to make sure an excessive input does not burn components on the board.

Arduino Mega has 53 digital I/O pins.

Figure 1: Arduino Mega

Traffic Lights:

This module consists of three lights, namely, Red, Yellow and Green.

All three lights have separate input pins through which each light is controlled independently.

Make sure you connect all three pins to the Arduino, even if you are not using a certain light. This is because Proteus simulation only works when all the pins of traffic light are connected.

Figure 2: Traffic Lights

Proteus Simulation of Traffic Light Control:

We will first make the circuit on our Proteus software, after doing the connections of the circuit, we will work on the Arduino code based upon the circuitry and connections made.

First of all, make sure you have downloaded and installed Proteus software on your system and have downloaded and integrated the required libraries with the downloaded software.

Open Proteus and then open a new project, there is no need to change settings and simply select okay to default selected settings.

Import all the components of this project mentioned above and shown in the figure below:

Figure 3: Required Components

Place the components in the worksheet as illustrated below:

Figure 4: Component Placement

After placing the components in the worksheet, make connections as follows:

  • Connect 0,1 and 2 digital pins of Arduino to red, yellow and green of traffic light 1 respectively.
  • Connect 3,4 and 5 digital pins of Arduino to red, yellow and green of traffic light 2 respectively.
  • Connect 6,7 and 8 digital pins of Arduino to red, yellow and green of traffic light 3 respectively.
  • Connect 9,10 and 11 digital pins of Arduino to red, yellow and green of traffic light 4 respectively.
  • Connect 12and 13 digital pins of Arduino to red and green LEDs of pedestrian light 1 respectively.
  • Connect 14 and 15 digital pins of Arduino to red and green LEDs of pedestrian light 2 respectively.
  • Connect 16 and 17 digital pins of Arduino to red and green LEDs of pedestrian light 3 respectively.
  • Connect 18 and 19 digital pins of Arduino to red and green LEDs of pedestrian light 4 respectively.
  • Ground the negative terminals of all LEDs.

With this, your circuit connections are complete and we will now move on to the firmware setup of this circuit.

Arduino Code:

We have divided the Arduino code into 3 segments:

  • Declaration Code
  • Void setup
  • Void loop

We will look at these sections separately now.

Declaration Code:

The first step in the code is the declaration of variables that we will utilize in our program. At first is the declaration of traffic lights and setting them up with their respective pins of Arduino board. The syntax of this code is as follows.

Figure 5: Arduino Code

The next declaration is of pedestrian lights. The syntax of pedestrian light declaration is illustrated as follows.

Figure 6: Arduino Code

Void Setup:

This part of the code along with the declaration part is run only once, we will use this to define output and input pins. This helps Arduino to understand which pins to take data from and which pins to write data on.

Since there is no input, we will only define traffic lights and pedestrian lights as output pins. The syntax to do this is shown in figure 7.

Figure 7: Arduino code, Void Setup

Void Loop:

This part of the code runs in a loop consistently and is used to write the main section of the code.

In the first section, we will turn on the green light of signal 1 while all other signals are red. The pedestrian lights are red for pedestrian signals 1, 2 and 3. While the pedestrian 4 light is green since it is opposite to traffic signal 1.

Figure 8: Arduino Code

After a delay of 2000ms, we will turn on the yellow light for signal 1 and signal 2 to indicate that a transition from signal 1 to signal 2 will be made shortly. We will also turn all pedestrian lights red in order to ensure pedestrian safety.

Figure 9: Arduino Code

After a delay of 1000ms, all traffic and pedestrian lights will turn off for 100ms.

Figure 10: Arduino Code

For the second signal, we will turn on the green light of signal 2 while all other signals are red. The pedestrian lights are red for pedestrian signals 2, 3 and 4. While the pedestrian 1 light is green since it is opposite to traffic signal 2.

Figure 11: Arduino Code

After a delay of 2000ms, we will turn on the yellow light for signal 2 and signal 3 to indicate that a transition from signal 2 to signal 3 will be made shortly. We will also turn all pedestrian lights red in order to ensure pedestrian safety.

Figure 12: Arduino Code

After a delay of 1000ms, all traffic and pedestrian lights will turn off for 100ms.

Figure 13: Arduino Code

For signal 3, we will turn on the green light of signal 3 while all other signals are red. The pedestrian lights are red for pedestrian signal 1, 3 and 4. While the pedestrian 2 light is green since it is opposite to traffic signal 3.

Figure 14: Arduino Code

After a delay of 2000ms, we will turn on the yellow light for signal 3 and signal 4 to indicate that a transition from signal 3 to signal 4 will be made shortly. We will also turn all pedestrian lights red in order to ensure pedestrian safety.

Figure 15: Arduino Code

After a delay of 1000ms, all traffic and pedestrian lights will turn off for 100ms.

Figure 16: Arduino Code

For the final signal, we will turn on the green light of signal 4 while all other signals are red. The pedestrian lights are red for pedestrian signals 1, 2 and 4. While the pedestrian 3 light is green since it is opposite to traffic signal 4.

Figure 17: Arduino Code

After a delay of 2000ms, we will turn on the yellow light for signal 4 and signal 1 to indicate that a transition from signal 4 to signal 1 will be made shortly. We will also turn all pedestrian lights red in order to ensure pedestrian safety. This will also complete the loop and the sequence will keep running on its own.

Figure 18: Arduino Code

After a delay of 1000ms, all traffic and pedestrian lights will turn off for 100ms.

Figure 19: Arduino Code

With this, the program of the void loop will end and start again from signal 1 on its own.

Results/Working:

Generate a hex file from the Arduino program made above. Be sure to select

Integrate the hex file into your Arduino board on Proteus.

Run the simulation.

The results of the simulation should be something like our simulation results.

The simulation results for each scenario are illustrated in the figure below.

At first, traffic signal 1 is turned ON and the green light is displayed for 2000ms. The green pedestrian light 4 is also turned ON since it is opposite to signal 1.

Figure 20: Signal 1 is ON while Pedestrian 4 is ON.

Then the yellow light of signals 1 and 2 are turned ON showing transition is about to happen. The red pedestrian lights during this are turned ON to ensure pedestrian safety.

Figure 21: Yellow light showing the transition.

Then traffic signal 2 is turned ON and the green light is displayed for 2000ms. The green pedestrian light 1 is also turned ON since it is opposite to signal 2.

Figure 22: Signal 2 is ON while Pedestrian 1 is ON.

Then the yellow light of signal 2 and 3 is turned ON showing transition is about to happen. The red pedestrian lights during this are turned ON to ensure pedestrian safety.

Figure 23: Yellow light showing transition.

Then traffic signal 3 is turned ON and the green light is displayed for 2000ms. The green pedestrian light 2 is also turned ON since it is opposite to signal 3.

Figure 24: Signal 3 is ON and Pedestrian 2 is ON

Then the yellow light of signal 3 and 4 is turned ON showing transition is about to happen. The red pedestrian lights during this are turned ON to ensure pedestrian safety.

Figure 25: Yellow light showing the transition.

Then traffic signal 4 is turned ON and the green light is displayed for 2000ms. The green pedestrian light 3 is also turned ON since it is opposite to signal 4.

Figure 26: Signal 3 is ON and Pedestrian 2 is ON

Then the yellow light of signal 4 and 1 is turned ON showing transition is about to happen. The red pedestrian lights during this are turned ON to ensure pedestrian safety.

Figure 27: Yellow light showing the transition.

That is all for today’s tutorial, I hope you enjoyed learning with us. We wish you have a good day ahead of you. Thanks for reading.

THT vs SMT

Hello everyone, I hope you all are doing great. Today, we are going to share the 9th chapter in the PCB learning series, where we will have a look at the difference between Through-hole and Surface-mount technology.

In our previous lectures, we studied both THT and SMT methods separately and have seen that both are used for components mounting on the PCB board. So, today, we will have a look at the difference between the two techniques. So, let's get started without wasting any time.

Through-Hole vs Surface-Mount

Let us know have a look at these differences and get to know the way forward when it comes to the process of component selection whether SMT or DIP.

Definition - THT vs SMT

  • THT stands for through-hole technology.

In Through-hole technology, components are mounted by the use of holes that are systematically drilled through the layers of printed circuit boards. the components have long leads that are properly fitted in the holes and soldered.

  • SMT method stands for Surface Mount Technology.

In Surface-mount technology, components are mounted on the surface of the printed circuit board. This is the most recent method employed in manufacturing of printed circuit boards.

How to Manufacture?

There are many online PCB Manufacturing companies, where you can place your SMT or THT orders. For example, let's talk about JLCPCB Fabrication House, they offer both THT and SMT fabrication. You can place your order on the official site of JLCPCB. They have an excellent support team, so while placing your order, you can discuss your design with them and they will guide you completely.

JLCPCB offers competitive prices as compared to other PCB houses and delivers quality work within the assigned time limit. They also offer seasonal discounts, so if you are a regular PCB designer, you should subscribe to JLCPCB.

Component Mounting

Through-hole Technology:

  • In Through-hole Technology, DIP components are used having copper leads/wires called lead wire terminals.
  • These leads are used to connect the components with copper tracks on the PCB board.
  • These leads are inserted in the drilled holes on the PCB board and are soldered from the back side.
  • The extra leads are then trimmed off using a cutter.
  • A DIP component having two leads is shown in the below figure:

Surface-mount Technology;

  • In Surface-mountTechnology, SMT components are used having copper flat terminals(called pads) instead of leads/wires.
  • These SMT components are placed on the surface of the PCB board as mentioned in the design files and the flat terminals are soldered with the pads of the PCB board.
  • An SMT component is shown in the below figure:

Manual vs Automatic Process

Through-hole Technology

  • Through-hole PCB boards can be assembled both manually and automatically(with the help of machines).
  • Normally manual assembling is preferred in THT boards.

Surface-mount Technology

  • As the SMT circuits are complex in design, thus it involves the use of sophisticated systems to ensure that the process is accurate and error-prone.
  • Pick-and-place machines and stencils are used in the SMT process.
  • Manufacturing SMT PCB at home is too difficult so automatic processes are recommended in this case.

Stencils

Stencil is a modern technique to place solder paste on a bare circuit board. This paste forms the deposits on the board that is used to hold the components in place.

Through-hole Technology:

  • The through-hole technology does not involve the use of stencils since the components are mounted in holes and are soldered on the other side.

Surface-mount Technology

  • The surface mount technology uses stencils for the process to be smooth.
  • Solder paste is poured through a stencil on the PCB board and then SMT components are placed on it.

Vias

Vias are small drilled holes between the PCB layers to electrically join traces of the circuitry.

[TEPImg11]

Through-hole Technology

  • For the through-hole technology, vias are not that necessary since the components are connected through the holes to the other layers of the boards.

Surface-mount Technology

  • The surface-mount devices employ the use of the vias to connect between layers of the board. Since components are mounted on the same layer, it is very necessary to employ the vias to interconnect between the layers of the PCB board.

Debugging

  • Through-hole technology mounting components and boards are quite easy to debug/repair, that's why, THT is used when a prototype or testing is required.
  • Surface-mount technology components are quite difficult to debug/repair because they are very small in size.

Soldering

Through-hole Technology

  • Wave Soldering is used in THT boards.
  • It's an in-line soldering process that treats the solder with flux.
  • The solder is melted after getting heated and then immersed on the PCB board.
[TEPImg12]

Surface-mount Technology

  • Reflow soldering is used in SMT boards.
  • In reflow soldering, a solder paste is used to mount components temporarily on the board by the use of the pads after which the entire design is preheated.
[TEPImg13]

Component Types

  • Through-hole technology uses lead capacitors and resistors, DIP and GPA components.
  • The surface mount technology uses LCCCP, SPOIC, QFP, BGA, SOT, LCC, chip resistors/capacitors etc.

Assembly Density

  • Through-hole technology is used when a low density of components is required.
  • Surface mount technology is used where a high density of components is required.

Solder Joint

Through-hole Technology

  • For the through-hole technology, the solder joint connects the component lead to the board through a hole drilled on it.
  • The solder is applied on the lower side of the board and the upper side is filled with the flux.

Surface-mount Technology

  • For the surface mount devices, the board is first spread with the solder paste, after that components with pads are placed accordingly on the soldered points and then the solder is melted to fix the components on the board.

Cost of Production

The cost of production for the two methods varies, normally determined by the type of manufacturing process and the components used.

Through-hole Technology

  • Through-hole technology proves to be the most expensive. when it comes to initial production because it involves drilling holes to mount the components.
  • But when it comes to routine maintenance of the THT boards, the cost is relatively low since it is very easy to replace any component on the boards. THT is easily repairable.

Surface-mount Technology

  • Surface-mount devices are cheaper when it comes to initial manufacturing.
  • The process is purely automated hence saving oh human labor costs.
  • Also, the process does not involve the use of holes in the mounting of the components hence reducing costs.
  • The boards are produced in bulk through the process of PCB panelization, this also lowers the cost of production of the boards.
  • Now, there is one challenge with this type of board, the maintenance cost is too demanding. You will need a lot of expertise to change any faulty component. Some of them cannot be changed since they are so tiny. Therefore, in most cases, if the board has a problem, you might end up buying a new one hence it is very expensive when it comes to maintenance and repair.

Applications

Through-hole Technology

  • Through-hole technology is preferred in hobbyists and academic projects, because of simple circuits to design.
  • THT Boards are also used in areas where strong mechanical strength is required such as in military equipment and equipment with high vibrations. This is because their soldered joints are mechanically strong.

Surface-mount Technology

  • Surface-mount devices are preferred in the industry sector where commercial products are designed because SMT is cheap, lightweight and small in size.
  • The manufacturing time of SMT boards is quite low, especially in mass production, because its manufacturing process is purely automated.

So, that was all for today. I hope you have enjoyed today's lecture, let me know if you need any help with it. Thanks for reading.

Syed Zain Nasir

I am Syed Zain Nasir, the founder of <a href=https://www.TheEngineeringProjects.com/>The Engineering Projects</a> (TEP). I am a programmer since 2009 before that I just search things, make small projects and now I am sharing my knowledge through this platform.I also work as a freelancer and did many projects related to programming and electrical circuitry. <a href=https://plus.google.com/+SyedZainNasir/>My Google Profile+</a>

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Syed Zain Nasir