Hi learners! I hope you are doing great. Today, I am going to share the second version(V2.0) of the LCD library for Proteus. We have already shared the LCD V1.0 Library on our blog. Along with appreciation, we also get some complaints/suggestions about that library. So, we have designed a better version of the LCD library by keeping the suggestions in mind.
Version 2.0 has error-free working, better pinout prints, and is identical to the real-world LCD. We have also removed our website link from the LCD. This library includes two alphanumeric LCDs in it i.e. LCD 16x2 and LCD 20x4.
If you don't have any experience with the LCD, no need to worry as we will guide you from scratch. Before installing the LCD, let's first have a look at its brief introduction:
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Battery 12V | Amazon | Buy Now | |
| 2 | Resistor | Amazon | Buy Now | |
| 3 | LCD 16x2 | Amazon | Buy Now | |
| 4 | LCD 20x4 | Amazon | Buy Now | |
| 5 | PIR Sensor | Amazon | Buy Now | |
| 6 | Arduino Uno | Amazon | Buy Now | |
Let's have a look at the pinout of LCD:
Both of these LCDs(16x2 and 20x4) have similar pinouts and a simple basic circuit needs to be designed in order to operate them. There are a total of 16 pins present in LCD used for different purposes. The below table has the complete description of LCD Pinout:
Serial |
Pin |
Functionality |
Description |
1 |
VSS |
Ground |
This pin is connected to the ground terminal of the circuit. |
2 |
VDD |
Power Supply |
It is connected to the positive voltage(+5V) and is responsible for the power supply to all pins. |
3 |
VEE |
Voltage Emitter |
It is used to control the contrast of LCD. it applies the negative voltage and thus controls the electric field of the LCD. |
4 |
RS |
Register Select |
It selects the LCD register. LCD has two registers: an instruction register and a data register. |
5 |
RW |
Read or write |
The read-and-write operation is done through this pin. if set to HIGH then LCD is in reading mode and LOW means it is writing the data. |
6 |
E |
Enable |
Enables the working of LCD. If HIGH then allow the display and if LOW then disable it. |
7-14 |
D0-D7 |
Data bits (Pins to deal with the data) |
Data is sent to the LCD in a parallel manner. These pins send this data and out of these, D0 is the least significant and D7 is the most significant. |
The installation of the LCD V2.0 is simple. The first step is to download the library files. I believe you have Proteus installed. So, click the below button to download the Proteus Library zip file.
The zip file also contains the project, where we simply connected both the LCDs with Arduino, so that you could check their working. Moreover, code is also present in the file.
Once the Library is installed, you need to open your Proteus software. If it's already open, you have to restart it. Now follow the instructions.
I have installed both versions therefore, I am getting four options. I will choose the LCD 20X4 V2.0 and LCD 16X2 V2.0.
Click on the components and simply place them on the working sheet of Proteus, it will appear as shown below:
Now, let's design an LCD simulation in Proteus:
Now, let's design a simple LCD simulation, where we will interface it with an Arduino UNO board. We will display our website's link on the LCD. So, let's design the circuit:
Go to the pick library and select the following components:
Now let's design the Arduino code to display data on these LCDs:
Now, open your Arduino software, I hope you have it installed. Paste the below code in it, I have also added this code in the zip file.
#include
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(13, 12, 11, 10, 9, 8);
void setup() {
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);
// Print a message to the LCD.
lcd.setCursor(1,0);
lcd.print("www.TheEngineering");
lcd.setCursor(4,1);
lcd.print("Projects.com");
}
void loop() {
}
The next step is to get the Hex File from Arduino IDE and add in the Proteus. For this, follow these steps:
If you have followed all the steps, I am sure your project will run successfully. I hope it was helpful to you. You must practice it more and try to make different projects. So, that was all for today, will meet you guys in the next tutorial. Take care!!!
Hello friends, I hope you all are having fun. In today's tutorial, I am going to share a new Proteus library for Raspberry Pi 2. We have already shared the Proteus Libraries of other Raspberry Pi modules i.e. Raspberry Pi 4, 3, Pico etc. and we discussed that these Pi modules won't be able to read the Python code. We have just designed the external appearance of these modules and you can use these Pi modules for circuit designing and project presentations.
We have also added the Arduino firmware in these boards, which is just to provide a bit of interaction with these boards. We have given these boards an unofficial title "Arduino Pi".
So, let's have a look at How to simulate Raspberry Pi in Proteus:
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Battery 12V | Amazon | Buy Now | |
| 2 | LEDs | Amazon | Buy Now | |
| 3 | Resistor | Amazon | Buy Now | |
| 4 | LCD 16x2 | Amazon | Buy Now | |
| 5 | LCD 20x4 | Amazon | Buy Now | |
| 6 | PIR Sensor | Amazon | Buy Now | |
Raspberry Pi 2 Library for Proteus
Note: For a better understanding, you should read How to Add a New Library File in Proteus.
Note: Its design is quite similar to that of Raspberry Pi 3, although we added the name to differentiate between the two.
As mentioned above, this Pi board won't be able to read the Python code. So, we have added the Arduino firmware in it to make it a bit more interactive. So, let's blink an LED with this Raspberry Pi 2 module in Proteus:
So, that was all for today. I hope you have enjoyed these Raspberry Pi simulated modules. IF have any questions, please ask in the comments. Thanks for reading.
Greetings, and welcome to another tutorial in our series on the raspberry pi 4 Python programming. The previous guide covered the basics of transmitting data over the radio using the nrf24l01 chip in Pi 4. We also learned about interfacing Arduino and raspberry pi 4 and sending radio signals between the two devices. However, this tutorial will walk you through building a Raspberry Pi-based mobile phone with a microphone and speaker for making and receiving calls and reading text messages (SMS). This Project also serves as a proper GSM Module for the Raspberry Pi interface, with all the necessary Code to run the most fundamental features of any modern smartphone. First, we will understand what gsm is, its architecture and how it works, then we will learn how to program it in our pi 4; therefore, let us begin.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Jumper Wires | Amazon | Buy Now | |
| 2 | LCD 16x2 | Amazon | Buy Now | |
| 3 | Raspberry Pi 4 | Amazon | Buy Now | |
Raspberry Pi 4
GSM Module
16x2 LCD
4 *4 Keypad
10k pot
Breadboard
Connecting jumper wire
Power supply
Speaker
Microphone
SIM Card
Loudspeaker
The acronym "GSM" refers to the "global system for mobile communication" and is the name of a type of mobile communication modem (GSM). Bell Labs was responsible for conceptualizing GSM in the 1970s. It's one of the most common forms of mobile communication around the globe. The 850MegaHertz, 900MegaHertz, 1800 Megahertz, and 1900 Megahertz frequency bands are utilized by GSM networks, which are part of an open and digital mobile network used to carry voice and data services.
Using the telecommunications method of multiple time division access (TDMA), GSM technology was created as a digital system. For transmission, a GSM converts analog signals to digital ones, compresses them further and delivers them through a channel sharing bandwidth with two data streams from separate clients. The data rates transported by the digital system range from 64 kilobytes per second to 120 Megabytes per second.
In a GSM network, macro, micro, and umbrella cells coexist. The implementation context determines the specifics of each cell. The macro, micro, and umbrella cell sizes are in use in a GSM network. Each cell may have a different range of coverage depending on the setting.
Time-division multiple access (TDMA) works by giving each user a specific amount of time to transmit on the same frequency. It's flexible, supporting data rates from 64kbps to 120Mbps and allowing for clear voice communications.
The following are the primary components of the GSM architecture.
Connectivity and Switching Infrastructure (NSS)
All three of these components—the Base Station (BS), the Mobile Station (MS), and the Operations and Maintenance Subsystem (OSS)—are necessary for proper communication (OSS)
Each component of the GSM system design contributes to what is collectively called the core system/network. In this case, the mobile network system is primarily controlled and interfaced with via a data network consisting of several different components. Listed below are some of the most crucial elements of the underlying network.
One of the essential parts of a GSM network is its core network, where the Mobile Switching Center (MSC) resides. This MSC performs the same functions as a common switching node in an ISDN or PSTN. Still, it provides additional features to accommodate mobile users' requirements, such as authentication, registration, inter-MSC handovers, call localization, and routing.
In addition, it gives users an advantage in connecting their mobile phone networks to the PSTN (public switched telephone network) for making and receiving landline calls. To facilitate mobile-to-mobile calls across different networks, interfaces to all other switched telephone networks ( PSTN center servers are given.
Every subscriber's administrative details, including their last known location, are stored in this HLR database. This manner, calls can be routed over the GSM network to the appropriate mobile switch base station. If a call comes in when an operator has their phone turned on, the network can determine which base transmitter station the call is coming from and link it to the correct phone.
When the phone is turned on but not being used, it nevertheless registers to ensure the HLR system is aware of its current location. Each network has a single HLR, which may be physically split across several data centers for practical reasons.
To facilitate the VLR's desired services for the individual subscriber, it incorporates data from the HLR network. It is possible to run the visitor coordinates register independently, but it is most commonly implemented as a core component of the MSC. Because of this, getting access is more manageable, and it takes less time overall.
The Equipment Identity Register (EIR) is the part of the network infrastructure in charge of deciding whether or not certain pieces of mobile equipment are allowed access. The International Mobile Equipment Identification (IMEI) numbers uniquely identify each mobile technology work.
This IMEI number is permanently embedded within the mobile device and checked by the network after registration. Depending on the data in the EIR, the mobile phone may be given one of three possible network access states: allowed, banned, or monitored.
When users insert their SIM card into their phone, the secret key is stored in a secure file known as the AUC (authentication center). The AUC sees the extensive application as a radio channel coding and verification standard.
In the absence of location information for the mobile station (MS), a call placed by a ME terminates with the GMSC (Gateway Mobile Switching Centre). Using the Mobile Subscriber Identifier Service Data Number (MSISDN) and the HLR, the GMSC can locate the specific MSC that has been visited and connect the call to the appropriate location. It's unclear what the "MSC" part of GMSC stands for, as the gateway procedure does not require relating to an MSC.
Both SMS-Gateways are referred to collectively as the SMS gateway in the GSM specifications. The messages passing via these gateways are directed in various ways.
Sending a short message to mobile equipment (ME) requires the usage of the Short Messaging Service Gateway Switching Center. Short messages sent over a mobile network are routed through the SMS Inter-Working Switching Center. While the SMS-primary GMSC's function concerns the GMSC, the SMS-IWMSC serves as a constant endpoint for access to the Short Message Service Centre.
These were the primary nodes in the GSM system's infrastructure. While they frequently shared physical space, the entire middle network would sometimes be broadcast throughout the country. In the event of a failure, it will provide a degree of leeway.
The connection point between the mobile node and the broader network infrastructure. The radio transceivers and protocol management for mobile devices are housed in the Base Transceiver Station. In addition, a Base Station Controller manages the Base Transceiver and serves as a bridge between mobile devices and the mobile switching hub.
The network subsystem handles connectivity between the network and the mobile stations. The Phone Service Switch Centre is the backbone of the Network Subsystem, allowing users to connect to other networks (ISDN, PSTN, etc.). The GSM system's ability to route calls and allow for roaming depends on two additional components, the Home Location Record and the guest Location Record.
In addition, it stores the Equipment Identity Register, which keeps track of all the mobile devices and their associated IMEI numbers. The acronym IMEI refers to the unique identifier for mobile devices worldwide.
In the second generation of GSM network design, the mobile devices communicate with the BSS, or Base Station Subsystem. These components comprise this subsystem, and each will be examined.
As part of a GSM network, the radio Tx, Rx, and their associated antennas make up the base Transceiver Station, which is used for transmitting, receiving, and communicating directly through mobiles. The base station is the central component of each cell, and it communicates with mobile devices using an interface known as the Um interface and related protocols.
The base station controller (BSC) is employed for the following step back into GSM technology. This controller is typically co-located within one of the base transceiver stations it controls. This controller handles radio resource management, including channel allocation and handover between base station groups. Over the Abis interface, it communicates with the BTSs.
The acceptable radio technology is used by the GSM network's subsystems component in the ground station to ensure that multiple operators can utilize the system at the same time. Each base station can support many operators because each channel can support up to eight users.
The network provider strategically places these to ensure comprehensive coverage. A base station, sometimes known as a "cell," can surround this space. Signals can't be prevented from bleeding into neighbouring cells, and the channels used in one don't transfer to the next.
Mobile phones include a transceiver, a display, and a CPU, all of which are network-connected and operated using a SIM card. In a GSM mobile transmission medium, the operator monitors and controls the mobile station or mobile equipment, which are most commonly represented by cell phones. Their size has shrunk significantly while their functionality has skyrocketed. The benefit of a much longer interval between charges is still another advantage. Phone hardware and the subscriber identity module (SIM) are two of many components.
A mobile device's hardware consists of its primary components, such as the housing, screen, battery, and electronics used to generate the signal and process the signal receiver before transmission. The IMEI is a unique number assigned to each mobile device. This feature can be permanently programmed into a phone throughout its manufacturing process. During the registration process, the network accesses this database to see if the device has been flagged as stolen.
A user's identity on the network is stored in the information contained in their SIMcard. It also includes other data, such as the IMSI number. With this IMSI stored in the Sim, the phone user could easily switch phones by swapping SIM cards. As a result, if switching to a new mobile phone were simple and didn't require a unique phone number, more people would do it, generating more revenue for network operators and contributing to GSM's overall economic triumph.
The OSS is an integral aspect of any functional GSM network. The NSS and BSC parts are linked here. The GSM network and BSS traffic load are the primary areas of focus for this OSS. It is worth noting that some preservation responsibilities are relocated to the base station controller to lower the maintenance expense of the system when the amount of BS increases through the consumer population growth.
The 2G GSM network architecture is predicated on a rational functioning method. This approach is remarkably straightforward compared to today's mobile network architectures, which rely on software-defined units to facilitate highly adaptable operations. However, the 2G GSM architecture will show how the necessary voice and essential operational functions are organized.
The following are some of the functions provided by the GSM module.
Enhanced spectrum efficiency
Features including "international roaming," "integrated services digital network" (ISDN) compatibility, and "support for future services" are also included.
High-quality voice communications; encrypted phone conversations;
Features like a programmable alarm clock, high-quality voice communication, a fixed calling number, a real-time clock, and the ability to send and receive SMS messages are all standard on modern smartphones (SMS)
As a result of its rigorous security measures, the GSM system is currently the safest available for use in the telecommunications industry. Call privacy and subscriber anonymity for GSM users are only protected during transmission, but this is still a massive step toward attaining end-to-end security.
In either its mobile phone or modem form, a Global System for Mobile Communications (GSM) modem enables two computers or processors to connect across a network. A SIM card is needed to run a GSM modem, and it can only be used within the coverage area the network provider has paid for. It has serial, USB, and Bluetooth connectivity options for linking to a personal computer.
Any regular GSM cell phone can double as a GSM modem if you have a suitable cable and driver installed on your PC. It would be best if you used a GSM modem instead of a GSM cell phone. The GSM modem is helpful in many devices, including POS terminals, inventory management systems, surveillance cameras, weather stations, and GPRS-mode remote data loggers.
Below is a circuit showing how to connect a GSM modem to the MC using the level-shifting IC Max232. When a numeric command is received by short message service (SMS) from any mobile device, the SIM card-mounted GSM modem transfers that information to the MC via serial connection. The GSM modem is programmed to respond to the order "STOP" by producing an MC output, the point which is utilized to deactivate the ignition switch.
If the input is driven low, the GSM modem will send a predetermined message (in this case, "ALERT") to the user. A 162 LCD screen displays the entirety of the procedure.
We have utilized a GSM module and a Raspberry Pi 4 to manage the entire system and interface its many parts in this Project. You can input data of any kind, including phone numbers, text messages, and phone calls, read and respond to text messages, and more, using a 4x4 alphanumeric keypad. The SIM900A GSM module connects mobile phones to wireless networks for making and receiving calls and sending and receiving text messages. We've integrated a microphone, a loudspeaker for making and receiving voice calls, and a 16 * 2 liquid crystal displays information like menu options and alarms.
With alphanumeric input, you can use the same keyboard to type in both numbers and letters. For the Code we used to allow alphabets in addition to numbers in this method, scroll down to the "Code in Code" section.
It's simple to put this plan into action. The alphanumeric keypad is used for all functions. Below you'll find a link to the complete Code and a demonstration video. This section will elaborate on the four aspects of the listed projects.
The Pi 4 phone we built requires us to press the letter "C" and provide the cellphone number we wish to call. We'll use an alphanumeric keyboard to enter the number. Once the correct number has been entered, we must hit "C" again. The AT command is now processed by pi 4 to connect the call to a specified number.
ATDxxxxxxxxxx; <Enter> where xxxxxxxxx is entered Mobile Number.
Answering a phone call is simple. When a call comes into the SIM number stored in the GSM Module of your system, the LCD will display the message "Incoming..." along with the caller's number. All that's left to do is hit the 'A' key to answer the call. Pi 4 will send the following command to the GSM Module when the "A" button is pressed:
ATA <enter>
Pressing "D" on our Raspberry Pi phone allows us to send a text message. To whom (or what) should we address the SMS message that the system has just requested? Once the number has been entered, pressing "D" again will prompt the LCD to request a message. To send an SMS, enter the message using the keypad as you would with any other mobile device, and then hit the 'D' key again. Raspberry Pi can send SMS with the following command:
AT+CMGF=1 <enter>
AT+CMGS=”xxxxxxxxxx” <enter> where: xxxxxxxxxx is entered mobile number
Even this component is easy to use. Here, the SIM card is used to receive SMS messages from the GSM. The Raspberry Pi also keeps a close eye on the UART SMS signal. New notes are shown by the LCD displaying the text "New message," and reading them is as simple as pressing the "B" key. This is an SMS Received signal:
+CMTI: "SM," 6 Where 6 is the message location where it is stored in the SIM card.
When the RPi detects the 'SMS received' signal, it will get the SMS storage location and instruct the Global system for mobile to read the message. Moreover, the LCD will flash the words "New Message" in a prominent location.
AT+CMGR=<SMS stored location><enter>
The GSM now delivers the saved message to the Raspberry Pi, and the Pi, having extracted the primary SMS, shows it on the LCD. When it comes to MIC and Speaker, there is no secret code.
The GPIO pins of the Raspberry Pi are wired to the RS, EN, D4, D5, D6, and D7 pins of the 16 * 2 liquid crystal display. A direct connection is made between the GSM module's Rx and Tx pins and the Raspberry Pi's Tx and Rx pins. Connectors R1, R2, R3, and R4 of a 4 * 4 keypad are connected to GPIOs 12, 16, 20, and 21, whereas pins C1, C2, C3, and C4 are connected to GPIOs 26, 19, 13, and 6. If you want to boost the audio volume from the GSM Module, you can join the microphone directly to the mic+ and mic- pins and the loudspeaker to the sp+ and sp- pins. The loudspeaker can be connected directly to the GSM module without using the Audio Amplifier circuit.
This Pi 4 mobile phone's programming interface may be challenging to novices—the programming language of choice for this Project is Python.
Here, we define the keypad() function to be used with a basic numeric keypad. We've also added a def alpha keypad(): for typing alphabets so that you may use the same keypad for both purposes. To make it compatible with the Arduino keypad library, we've given this keypad a wide range of new capabilities. This keypad only takes 10 presses to enter a whole string of text or a numeric value.
For example, if we push key 2 (abc2) once, the LCD will display the letter 'a.' If we press it again, the letter 'b' will take its place, and if we hit it three more times, the letter 'c' will appear in the same spot. After holding down a key for a short time, the LCD pointer will advance to the following available location. We can now proceed to the next character or number. Any other keys can be processed in the same way.
def keypad():
for j in range(4):
gpio.setup(COL[j], gpio.OUT)
gpio.output(COL[j], 0)
ch=0
for i in range(4):
if gpio.input(ROW[i])==0:
ch=MATRIX[i][j]
return ch
while (gpio.input(ROW[i]) == 0):
pass
gpio.output(COL[j],1)
def alphaKeypad():
lcdclear()
setCursor(x,y)
lcdcmd(0x0f)
msg=""
while 1:
key=0
count=0
key=keypad()
if key == '1':
ind=0
maxInd=6
Key='1'
getChar(Key, ind, maxInd)
.... .....
..... .....
To begin, we have declared the pins for the liquid crystal display, the keypad, and other components, as well as included the necessary libraries in this python script:
import RPi.GPIO as gpio
import serial
import time
msg=""
alpha="1!@.,:?ABC2DEF3GHI4JKL5MNO6PQRS7TUV8WXYZ90 *#"
x=0
y=0
MATRIX = [
['1','2','3','A'],
['4','5','6','B'],
['7','8','9','C'],
['*','0','#','D']
]
ROW = [21,20,16,12]
COL = [26,19,13,6]
... .....
..... .....
The pins need to be pointed in the proper direction.
gpio.setwarnings(False)
gpio.setmode(gpio.BCM)
gpio.setup(RS, gpio.OUT)
gpio.setup(EN, gpio.OUT)
gpio.setup(D4, gpio.OUT)
gpio.setup(D5, gpio.OUT)
gpio.setup(D6, gpio.OUT)
gpio.setup(D7, gpio.OUT)
gpio.setup(led, gpio.OUT)
gpio.setup(buz, gpio.OUT)
gpio.setup(m11, gpio.OUT)
gpio.setup(m12, gpio.OUT)
gpio.setup(button, gpio.IN)
gpio.output(led , 0)
gpio.output(buz , 0)
gpio.output(m11 , 0)
gpio.output(m12 , 0)
To begin Serial communication, follow the steps below.
Serial = serial.Serial("/dev/ttyS0", baudrate=9600, timeout=2)
We must now create a liquid crystal display driving function. The def lcdcmd(ch): and def lcdwrite(ch): functions are used to deliver commands and data to the LCD, respectively. The liquid crystal display may also be cleared with def lcdclear(), the cursor position can be set with def setCursor(x,y), and a string can be sent to the liquid crystal display with def lcdprint(Str).
def lcdcmd(ch):
gpio.output(RS, 0)
gpio.output(D4, 0)
gpio.output(D5, 0)
gpio.output(D6, 0)
gpio.output(D7, 0)
if ch&0x10==0x10:
gpio.output(D4, 1)
.... .....
..... ....
def lcdwrite(ch):
gpio.output(RS, 1)
gpio.output(D4, 0)
gpio.output(D5, 0)
gpio.output(D6, 0)
gpio.output(D7, 0)
if ch&0x10==0x10:
gpio.output(D4, 1)
if ch&0x20==0x20:
gpio.output(D5, 1)
.... .....
..... ....
def lcdclear():
lcdcmd(0x01)
def lcdprint(Str):
l=0;
l=len(Str)
for i in range(l):
lcdwrite(ord(Str[i]))
def setCursor(x,y):
if y == 0:
n=128+x
elif y == 1:
n=192+x
lcdcmd(n)
Next, we'll need to code some features for interacting with text messages, phone calls, and incoming calls.
The call is placed using the function def call():. Also, the LCD can display the receiving message and number via the function def receiveCall(data):. Finally, the call is answered with def attendCall():.
The message is composed and sent using the alphaKeypad() method, accessed via the def sendSMS(): function. The SMS is received, and its location is retrieved using the def receive SMS(data) function. And finally, the LCD gets updated with the message thanks to def readSMS(index:).
All of the operations mentioned above are included in the Code that follows.
import RPi.GPIO as gpio
import serial
import time
msg=""
# 0 7 11 15 19 23 27 32 36 414244 ROLL45
alpha="1!@.,:?ABC2DEF3GHI4JKL5MNO6PQRS7TUV8WXYZ90 *#"
x=0
y=0
MATRIX = [
['1','2','3','A'],
['4','5','6','B'],
['7','8','9','C'],
['*','0','#','D']
]
ROW = [21,20,16,12]
COL = [26,19,13,6]
moNum=['0','0','0','0','0','0','0','0','0','0']
m11=17
m12=27
led=5
buz=26
button=19
RS =18
EN =23
D4 =24
D5 =25
D6 =8
D7 =7
HIGH=1
LOW=0
gpio.setwarnings(False)
gpio.setmode(gpio.BCM)
gpio.setup(RS, gpio.OUT)
gpio.setup(EN, gpio.OUT)
gpio.setup(D4, gpio.OUT)
gpio.setup(D5, gpio.OUT)
gpio.setup(D6, gpio.OUT)
gpio.setup(D7, gpio.OUT)
gpio.setup(led, gpio.OUT)
gpio.setup(buz, gpio.OUT)
gpio.setup(m11, gpio.OUT)
gpio.setup(m12, gpio.OUT)
gpio.setup(button, gpio.IN)
gpio.output(led , 0)
gpio.output(buz , 0)
gpio.output(m11 , 0)
gpio.output(m12 , 0)
for j in range(4):
gpio.setup(COL[j], gpio.OUT)
gpio.setup(COL[j],1)
for i in range (4):
gpio.setup(ROW[i],gpio.IN,pull_up_down=gpio.PUD_UP)
Serial = serial.Serial("/dev/ttyS0", baudrate=9600, timeout=2)
data=""
def begin():
lcdcmd(0x33)
lcdcmd(0x32)
lcdcmd(0x06)
lcdcmd(0x0C)
lcdcmd(0x28)
lcdcmd(0x01)
time.sleep(0.0005)
def lcdcmd(ch):
gpio.output(RS, 0)
gpio.output(D4, 0)
gpio.output(D5, 0)
gpio.output(D6, 0)
gpio.output(D7, 0)
if ch&0x10==0x10:
gpio.output(D4, 1)
if ch&0x20==0x20:
gpio.output(D5, 1)
if ch&0x40==0x40:
gpio.output(D6, 1)
if ch&0x80==0x80:
gpio.output(D7, 1)
gpio.output(EN, 1)
time.sleep(0.005)
gpio.output(EN, 0)
# Low bits
gpio.output(D4, 0)
gpio.output(D5, 0)
gpio.output(D6, 0)
gpio.output(D7, 0)
if ch&0x01==0x01:
gpio.output(D4, 1)
if ch&0x02==0x02:
gpio.output(D5, 1)
if ch&0x04==0x04:
gpio.output(D6, 1)
if ch&0x08==0x08:
gpio.output(D7, 1)
gpio.output(EN, 1)
time.sleep(0.005)
gpio.output(EN, 0)
def lcdwrite(ch):
gpio.output(RS, 1)
gpio.output(D4, 0)
gpio.output(D5, 0)
gpio.output(D6, 0)
gpio.output(D7, 0)
if ch&0x10==0x10:
gpio.output(D4, 1)
if ch&0x20==0x20:
gpio.output(D5, 1)
if ch&0x40==0x40:
gpio.output(D6, 1)
if ch&0x80==0x80:
gpio.output(D7, 1)
gpio.output(EN, 1)
time.sleep(0.005)
gpio.output(EN, 0)
# Low bits
gpio.output(D4, 0)
gpio.output(D5, 0)
gpio.output(D6, 0)
gpio.output(D7, 0)
if ch&0x01==0x01:
gpio.output(D4, 1)
if ch&0x02==0x02:
gpio.output(D5, 1)
if ch&0x04==0x04:
gpio.output(D6, 1)
if ch&0x08==0x08:
gpio.output(D7, 1)
gpio.output(EN, 1)
time.sleep(0.005)
gpio.output(EN, 0)
def lcdclear():
lcdcmd(0x01)
def lcdprint(Str):
l=0;
l=len(Str)
for i in range(l):
lcdwrite(ord(Str[i]))
def setCursor(x,y):
if y == 0:
n=128+x
elif y == 1:
n=192+x
lcdcmd(n)
def keypad():
for j in range(4):
gpio.setup(COL[j], gpio.OUT)
gpio.output(COL[j], 0)
ch=0
for i in range(4):
if gpio.input(ROW[i])==0:
ch=MATRIX[i][j]
#lcdwrite(ord(ch))
# print "Key Pressed:",ch
# time.sleep(2)
return ch
while (gpio.input(ROW[i]) == 0):
pass
gpio.output(COL[j],1)
# callNum[n]=ch
def serialEvent():
data = Serial.read(20)
#if data != '\0':
print data
data=""
def gsmInit():
lcdclear()
lcdprint("Finding Module");
time.sleep(1)
while 1:
data=""
Serial.write("AT\r");
data=Serial.read(10)
print data
r=data.find("OK")
if r>=0:
break
time.sleep(0.5)
while 1:
data=""
Serial.write("AT+CLIP=1\r");
data=Serial.read(10)
print data
r=data.find("OK")
if r>=0:
break
time.sleep(0.5)
lcdclear()
lcdprint("Finding Network")
time.sleep(1)
while 1:
data=""
Serial.flush()
Serial.write("AT+CPIN?\r");
data=Serial.read(30)
print data
r=data.find("READY")
if r>=0:
break
time.sleep(0.5)
lcdclear()
lcdprint("Finding Operator")
time.sleep(1)
while 1:
data=""
Serial.flush()
Serial.read(20)
Serial.write("AT+COPS?\r");
data=Serial.read(40)
#print data
r=data.find("+COPS:")
if r>=0:
l1=data.find(",\"")+2
l2=data.find("\"\r")
operator=data[l1:l2]
lcdclear()
lcdprint(operator)
time.sleep(3)
print operator
break;
time.sleep(0.5)
Serial.write("AT+CMGF=1\r");
time.sleep(0.5)
# Serial.write("AT+CNMI=2,2,0,0,0\r");
# time.sleep(0.5)
Serial.write("AT+CSMP=17,167,0,0\r");
time.sleep(0.5)
def receiveCall(data):
inNumber=""
r=data.find("+CLIP:")
if r>0:
inNumber=""
inNumber=data[r+8:r+21]
lcdclear()
lcdprint("incoming")
setCursor(0,1)
lcdprint(inNumber)
time.sleep(1)
return 1
def receive SMS(data):
print data
r=data.find("\",")
print r
if r>0:
if data[r+4] == "\r":
smsNum=data[r+2:r+4]
elif data[r+3] == "\r":
smsNum=data[r+2]
elif data[r+5] == "\r":
smsNum=data[r+2:r+5]
else:
print "else"
print smsNum
if r>0:
lcdclear()
lcdprint("SMS Received")
setCursor(0,1)
lcdprint("Press Button B")
print "AT+CMGR="+smsNum+"\r"
time.sleep(2)
return str(smsNum)
else:
return 0
def attendCall():
print "Attend call"
Serial.write("ATA\r")
data=""
data=Serial.read(10)
l=data.find("OK")
if l>=0:
lcdclear()
lcdprint("Call attended")
time.sleep(2)
flag=-1;
while flag<0:
data=Serial.read(12);
print data
flag=data.find("NO CARRIER")
#flag=data.find("BUSY")
print flag
lcdclear()
lcdprint("Call Ended")
time.sleep(1)
lcdclear()
def readSMS(index):
print index
Serial.write("AT+CMGR="+index+"\r")
data=""
data=Serial.read(200)
print data
r=data.find("OK")
if r>=0:
r1=data.find("\"\r\n")
msg=""
msg=data[r1+3:r-4]
lcdclear()
lcdprint(msg)
print msg
time.sleep(5)
lcdclear();
smsFlag=0
print "Receive SMS"
def getChar(Key, ind, maxInd):
ch=0
ch=ind
lcdcmd(0x0e)
Char=''
count=0
global msg
global x
global y
while count<20:
key=keypad()
print key
if key== Key:
setCursor(x,y)
Char=alpha[ch]
lcdwrite(ord(Char))
ch=ch+1
if ch>maxInd:
ch=ind
count=0
count=count+1
time.sleep(0.1)
msg+=Char
x=x+1
if x>15:
x=0
y=1
lcdcmd(0x0f)
def alphaKeypad():
lcdclear()
setCursor(x,y)
lcdcmd(0x0f)
msg=""
while 1:
key=0
count=0
key=keypad()
if key == '1':
ind=0
maxInd=6
Key='1'
getChar(Key, ind, maxInd)
elif key == '2':
ind=7
maxInd=10
Key='2'
getChar(Key, ind, maxInd)
elif key == '3':
ind=11
maxInd=14
Key='3'
getChar(Key, ind, maxInd)
elif key == '4':
ind=15
maxInd=18
Key='4'
getChar(Key, ind, maxInd)
elif key == '5':
ind=19
maxInd=22
Key='5'
getChar(Key, ind, maxInd)
elif key == '6':
ind=23
maxInd=26
Key='6'
getChar(Key, ind, maxInd)
elif key == '7':
ind=27
maxInd=31
Key='7'
getChar(Key, ind, maxInd)
elif key == '8':
ind=32
maxInd=35
Key='8'
getChar(Key, ind, maxInd)
elif key == '9':
ind=36
maxInd=40
Key='9'
getChar(Key, ind, maxInd)
elif key == '0':
ind=41
maxInd=42
Key='0'
getChar(Key, ind, maxInd)
elif key == '*':
ind=43
maxInd=43
Key='*'
getChar(Key, ind, maxInd)
elif key == '#':
ind=44
maxInd=44
Key='#'
getChar(Key, ind, maxInd)
elif key== 'D':
return
def sendSMS():
print"Sending sms"
lcdclear()
lcdprint("Enter Number:")
setCursor(0,1)
time.sleep(2)
moNum=""
while 1:
key=0;
key=keypad()
#print key
if key>0:
if key == 'A' or key== 'B' or key== 'C':
print key
return
elif key == 'D':
print key
print moNum
Serial.write("AT+CMGF=1\r")
time.sleep(1)
Serial.write("AT+CMGS=\"+91"+moNum+"\"\r")
time.sleep(2)
data=""
data=Serial.read(60)
print data
alphaKeypad()
print msg
lcdclear()
lcdprint("Sending.....")
Serial.write(msg)
time.sleep(1)
Serial.write("\x1A")
while 1:
data=""
data=Serial.read(40)
print data
l=data.find("+CMGS:")
if l>=0:
lcdclear()
lcdprint("SMS Sent.")
time.sleep(2)
return;
l=data.find("Error")
if l>=0:
lcdclear()
lcdprint("Error")
time.sleep(1)
return
else:
print key
moNum+=key
lcdwrite(ord(key))
time.sleep(0.5)
def call():
print "Call"
n=0
moNum=""
lcdclear()
lcdprint("Enter Number:")
setCursor(0,1)
time.sleep(2)
while 1:
key=0;
key=keypad()
#print key
if key>0:
if key == 'A' or key== 'B' or key== 'D':
print key
return
elif key == 'C':
print key
print moNum
Serial.write("ATD+91"+moNum+";\r")
data=""
time.sleep(2)
data=Serial.read(30)
l=data.find("OK")
if l>=0:
lcdclear()
lcdprint("Calling.....")
setCursor(0,1)
lcdprint("+91"+moNum)
time.sleep(30)
lcdclear()
return
#l=data.find("Error")
#if l>=0:
else:
lcdclear()
lcdprint("Error")
time.sleep(1)
return
else:
print key
moNum+=key
lcdwrite(ord(key))
n=n+1
time.sleep(0.5)
begin()
lcdcmd(0x01)
lcdprint(" Mobile Phone ")
lcdcmd(0xc0)
lcdprint(" Using RPI ")
time.sleep(3)
lcdcmd(0x01)
lcdprint("Circuit Digest")
lcdcmd(0xc0)
lcdprint("Welcomes you")
time.sleep(3)
gsmInit()
smsFlag=0
index=""
while 1:
key=0
key=keypad()
print key
if key == 'A':
attendCall()
elif key == 'B':
readSMS(index)
smsFlag=0
elif key == 'C':
call()
elif key == 'D':
sendSMS()
data=""
Serial.flush()
data=Serial.read(150)
print data
l=data.find("RING")
if l>=0:
callstr=data
receiveCall(data)
l=data.find("\"SM\"")
if l>=0:
smsstr=data
smsIndex=""
(smsIndex)=receiveSMS(smsstr)
print smsIndex
if smsIndex>0:
smsFlag=1
index=smsIndex
if smsFlag == 1:
lcdclear()
lcdprint("New Message")
time.sleep(1)
setCursor(0,0)
lcdprint("C--> Call <--A");
setCursor(0,1);
lcdprint("D--> SMS <--B")
Here are some examples of how GSM technology can be put to use.
Automation and Safety via Smart GSM Technology
Nowadays, we can't live without our GSM mobile terminal. The Mobile phone terminal is essentially an extension of ourselves, allowing us to connect with the world in the same way our wallet/purse, keys, or watch does. Many people like not having to worry about being unavailable or who they can call at any given moment.
It's clear from the name that this Project relies on the SMS transmission capabilities of GSM networks. The ability to send and receive text messages is widely utilized to provide access to equipment and facilitate home security breach management. There are two proposed subsystems in the system. Controlling appliances in one's house from afar is made possible by the appliance control subsystem, while the security alert subsystem provides automatic security monitoring.
The system can send consumers instructions via SMS from a designated phone number to adjust the home appliance's state as needed. An automatic SMS can be generated by the system upon detection of an intrusion, warning the user of a potential threat to their data.
The advent of GSM technology will make global, instantaneous, and universal communication possible. GSM's functional architecture employs intelligent networking principles as the first step toward a genuinely personal communication system with sufficient standards to ensure interoperability.
Medical Uses for GSM-Based Systems
Here are two examples of similar situations to think about.
The patient has sustained a life-threatening injury or illness and requires emergency medical attention. A mobile phone is the only thing he (or his companion) has.
After being released from the hospital, the patient plans to rest at home but is reminded that he must return for routine exams. A mobile phone and perhaps some health monitoring or other medical sensor gadgets may be in his possession.
The only way to solve either problem is via a mobile communication system. In other words, the above scenarios are easily manageable with today's communication technology because all that needs to be done is send the patient's information across a network and have it processed at the receiving end, which may be a hospital or the doctor's office.
In the first scenario, the doctor keeps tabs on the patient's information and returns the instructions to him so he can take whatever precautions before getting to the hospital. In the second scenario, the doctor keeps tabs on the patient's test results and, if necessary, proceeds with treatment.
Telemedicine services are the driving force behind this entire operation. The telemedicine system has three different applications.
Video conferencing lets patients in one location have face-to-face contact with their doctors and nurses, speeding up the healing process.
With the help of sensors that constantly report on a patient's condition and direct medical staff on how to proceed with treatment.
By sending the gathered health information for further review and analysis.
A wireless method of communication is used for the three options mentioned above. When providing healthcare, it is necessary to have many data retrieval mechanisms in place. These can be online medical databases or hosts with equipment that aid recovery and health monitoring. Broadband networks, medium-throughput media, and narrowband GSM access are all viable possibilities.
There are several benefits to using GSM technology in a telemedicine setup.
Cost savings and widespread availability of GSM receivers (including cell phones and modems)
It can transfer data quickly.
Typical Telemedical Infrastructure
The four components that make up a standard telemedicine system are as follows:
The Patient Unit: It takes data from the patient, either in its original analog form or after being converted to digital format, and then manages the data stream before sending it. It is made up of several different types of medical sensors, such as those used to track heart rate, blood pressure, body temperature, spirometry, etc., each of which generates an electrical signal that is sent to a processor or controller for analysis before being transmitted over a wireless network.
Communication Network: As such, it is employed for both data transmission and security. Networks, mobile stations, and base stations are all components of the Global System for Mobile Communication (GSM) system. The mobile station, also known as the mobile phone or primary mobile access point, is the device responsible for connecting mobile devices to the global system for mobile communications (GSM) network.
Receiving/Server Side: This is a healthcare system with a GSM modem installed to receive, decode, and forward signals to the presenting device.
Presentation Unit: This is the brains of the operation. This processor saves the data in a standard format for later retrieval and analysis by doctors and from which they can send text messages to the client side if necessary.
To demonstrate the fundamentals of telemedicine, a rudimentary model will suffice. It has a sender and a receiver, both of which are separate components. The sensor input is transmitted by the transmitter and received by the receiver unit for processing.
See below for a simplified telemedicine system to track a patient's heart rate and apply the results as needed.
The data collected by the heartbeat detector (a light-emitting device whose light is modified as it flows through human blood) is transformed into electrical pulses at the transmitter unit. When the Microcontroller picks up on these pulses, it calculates the heart rate and communicates that information and other data collected to the medical team via a Gsm network. An IC called a Max 232 connects the Microcontroller to the GSM modem.
The GSM modem at the receiving end grabs the information and passes it to the Microcontroller. The Microcontroller then performs an analysis using the input from the Personal computer and displays the outcome on the LCD. Medical professionals can keep tabs on the patient and begin the necessary treatment after reviewing the results on the screen.
The following are some real-world applications for GSM technology.
AT&T Health GlowCaps
These plain pill bottles serve as a gentle prompt to the patient to take their prescribed medications. It uses GSM technology to contact the patient on their mobile phone at the specified pill-taking time, at which point the cap will light up, the buzzer will sound, and the patient will be reminded to take their medication. Each time a bottle is uncorked, it is documented.
Ultrasound technology
With the help of a portable ultrasound transducer that connects to a smartphone, it is possible to send ultrasound images captured with a handheld device to a distant location using a global system for mobile communications (GSM).
A Continuous Glucose Monitor (CGM)
The patient's blood sugar levels can be tracked and reported to the doctor. A sensor is implanted under the skin and monitors blood glucose levels, sending the data to a receiver (a mobile phone) at regular intervals.
As part of this guide, we analyzed GSM's architecture and learned how it operates in practice. We wrote a Python program to turn our Raspberry Pi 4 into a fully functional mobile phone. No technical difficulties were encountered as we watched text and phone calls travel between the raspberry pi and our mobile phone. You should feel confident in your ability to apply the ideas and understand the circuits of GSM now. One way to up the difficulty level of this Project is to try to make a live video call using the raspberry pi 4 mobile. Next, we'll look at connecting the pcf8591 ADC/DAC analog-digital converter module to a Raspberry Pi.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Breadboard | Amazon | Buy Now | |
| 2 | Jumper Wires | Amazon | Buy Now | |
| 3 | LCD 16x2 | Amazon | Buy Now | |
| 4 | nRF24L01 | Amazon | Buy Now | |
| 5 | Arduino Uno | Amazon | Buy Now | |
| 6 | Raspberry Pi 4 | Amazon | Buy Now | |
We're glad you could join us for another lesson in our series on programming for the Raspberry Pi 4. The previous chapter covered how to interface the USB barcode scanner with raspberry pi 4. We looked at different types of barcodes and what each stripe represents as well as the different types of barcode scanners available today. We also built a python program for the intelligent shopping cart and now our familiarity with barcodes and scanners and how they function has significantly increased. The benefits and drawbacks of its use were also discussed, but what we're interested in for this article is the transmission of radio frequency signals using the nrf24l01 Module in a raspberry pi 4.
nRF24L01 RF module
Raspberry pi 4
Arduino Uno
Jumper wires
Power supply
16x2 liquid crystal display
Wireless communication systems, such as ESPS266 WiFi modules, are widely used in the design process. Further, the media chosen is determined by the function it will serve. It's no secret that the nRF24L01 is a widely used wireless channel for local area network communication. These modules have a band rate of 250Kbps to 2Mbps and transmit on the 2.4GHz (ISM band), which is permitted in many states and suitable for usage in industrial and healthcare settings. There is also the claim that these modules can communicate at a distance of up to 100 meters with the correct antennae.
This tutorial demonstrates how to set up wireless communication between an Arduino UNO and a Raspberry Pi by utilizing the nRF24L01 - 2.4GHz RF Transceiver module. Raspberry Pi will broadcast data via nRF24L01, and Arduino Board will receive the data and display it on a 16x2 LCD. In addition to its built-in WiFi and Bluetooth Low Energy (BLE) capabilities, the nRF24L01 is also capable of wireless communication via BLE.
Both parts of the tutorial are equally important. In the first, we'll see how to connect the nRF24L01 to an Arduino so that it can function as a receiver, and in the second, we'll do the same thing with a Raspberry Pi can send out signals.
There are many different types of electromagnetic waves. Still, the ones utilized for radar signals and communications fall into roughly 3 kHz to 300 GHz range, known as "radio frequencies."
The term "radio frequency" is more commonly used to refer to electrical than mechanical oscillations. There are, however, examples of mechanical RF systems. Although radio frequency (RF) refers to an oscillation rate, the term "radio frequency" (RF) is sometimes used interchangeably with "radio" to describe the practice of communicating without the need for wires.
Numerous wireless technologies rely on RF fields, including cordless and cell phones, radio and television broadcasting stations, satellite telecommunication networks, Bluetooth communication modules and WiFi, and two-way radios.
External communications include various products like garage doors and microwave ovens, which use radio frequencies. The infrared frequencies of various wireless devices, like TV remote controllers, computer mice, and some wireless computer keyboards, have shorter electromagnetic wavelengths.
The frequency of radio transmission is expressed in hertz (Hz) units, which stand for the count of cycles per second. Radio waves can travel from one thousand hertz (kHz) to several gigahertz (GHz). Microwaves, a form of radio wave, operate at much higher frequencies. Because of this, we can't see radio frequencies (RFs).
The wavelength' of a radio wave is proportional to the square root of the frequency 'f.' The relationship between frequency and wavelength can be expressed in megahertz and meters, respectively.
s = 300/f
At higher frequencies, electromagnetic radiation is manifested as infrared (IR), ultraviolet (UV), visible (Visible), X-ray (XR), and gamma-ray (GJ).
The following are some of the defining features of RF:
Low energy consumption
It has an excellent operational range (three to thirty meters), a data rate of up to two megabits per second, the ability to pass through walls, and can transmit in any direction.
Due to their half-duplex design, the nRF24L01 modules can only send or receive data but not do both. The Module's data transmission and reception are handled by the generic Nordic semi-conductor nRF24L01 IC. The IC uses the simple serial peripheral interface (SPI) protocol for communication, making it compatible with virtually all microcontrollers. Arduino makes things much simpler because there are numerous library resources available. The following table depicts the pin configurations of a typical nRF24L01 module.
The Module is battery efficient, as its operating voltage ranges from 1.9V to 3.6V, and it draws minimal current (only 12mA) during regular operation. Most pins can be connected directly with 5V chipsets like Arduino, even though the voltage rating is 3.3V. Each Module also includes 6 Pipelines, which is a huge time saver. Simply put, each Module can exchange information with up to six others. Therefore, the Module can be used for IoT applications requiring the creation of star or mesh networks. With an extensive network address of 125 unique IDs, we may use 125 such components in a contained space without worrying about them interfering with one another.
Given that the Module supports 125 separate channels, creating a network containing 125 fully available modems at a single location is theoretically possible. Each device can simultaneously interface with up to six others on the same channel.
Transmission with this Module only uses about 12mA of power, less than a single display LED screen. The Module requires a voltage of 1.9V to 3.6V to function. Still, the other pins are 5V logic compatible, allowing us to connect it directly to an Arduino without needing logic-level converters.
Three of these terminals are used for SPI communication and must be hooked up to the SPI pins on the Arduino; however, the SPI pins on different Arduino boards are labelled differently. Connecting the CSN and CE pins to any input pin on the Arduino board toggles between standby and active modes and transmit and command modes for the Module. The last connector is an interrupt pin, which is optional.
The NRF24L01 modules can be found in a wide range of versions. The model with a built-in antenna is the clear frontrunner. This reduces the transmission range of the Module to around 100 meters but allows for a smaller module size.
In the second variant, an SMA connector replaces the onboard antenna, allowing us to use a duck transmitter for enhanced signal strength.
The third variant displayed here also features the duck antenna with an RFX2401C microprocessor with an integrated Power Amplifier and Low-Noise Amplifier). This can increase the NRF24L01's transmission range in open areas by 1000.
The components in the circuit design for linking nRF24L01 to Arduino are few, and the process is straightforward. SPI will be used to link the nRF24l01, and I2C will connect the 16x2 LCD.
Because only the SPI adapter is required to link the Raspberry Pi and the nRF24L01, the corresponding circuit schematic is pretty straightforward.
Python3 will be used for Raspberry Pi's programming. The Arduino platform is not the only one that can use C/C++. However, if you're programming in Python, you can get a library for nRF24l01 that's already been made. Keep in mind that the library and the python program must be in the same folder for the python program to use it. Create a folder to house your applications and library files after you have downloaded and extracted the library. After the necessary libraries have been installed, you can begin coding immediately. Importing libraries like the GPIO library for communicating with the Raspberry Pi's GPIO pins and the time library for using the Pi's clock and date functions are the first steps in writing any program.
import RPi.GPIO as GPIO
import time
import spidev
from lib_nrf24 import NRF24
It would be best if you switched to the "Broadcom SOC channel" for the GPIO setting. Pins are referred to by their "Broadcom SOC channel" numbers, which follow the letters "GPIO" (GPIO01, GPIO02, etc.). The Board Numbers are not these.
GPIO.setmode(GPIO.BCM)
After that, we'll assign a permanent address for the pipe. To send data to Arduino, you'll need to use this address. There will be a hexadecimal representation of the address.
pipes = [[0xE0, 0xE0, 0xF1, 0xF1, 0xE0], [0xF1, 0xF1, 0xF0, 0xF0, 0xE0]]
Start the radio with the CE pin (GPIO08) and the CSN pin (GPIO25).
radio.begin(0, 25)
Change the power levels to minimal, the channel address to 76, the data rate to 1 Mbps, and the payload size to 32 bits.
radio.setPayloadSize(32)
radio.setChannel(0x76)
radio.setDataRate(NRF24.BR_1MBPS)
radio.setPALevel(NRF24.PA_MIN)
Start the data writing process by opening the pipes and displaying some nRF24l01 basics.
radio.openWritingPipe(pipes[0])
radio.printDetails()
Get your message ready to send as a string. Arduino UNO will receive this message.
sendMessage = list("Hi..Arduino UNO")
while len(sendMessage) < 32:
sendMessage.append(0)
Send the string's first character to the stereo and continue doing so until the radio is ready to receive it. In addition, a debug statement detailing the time and date the message was delivered should be printed.
While True:
start = time.time()
radio.write(sendMessage)
print("Sent the message: {}".format(sendMessage))
send
radio.start listening()
A timed-out error message should be printed if the thread is finished and the conduit is closed.
while not radio.available(0):
time.sleep(1/100)
If time.time() - start > 2:
print("Timed out.") # print error message if radio disconnected or not functioning anymore
break
If you want to send another message, turn off the radio and disconnect from the connection for three seconds.
radio.stopListening() # close radio
time.sleep(3) # give a delay of 3 seconds
If you know the fundamentals of Python, you can easily comprehend the Raspberry program. You will find a fully functional Python program at the end of this tutorial.
If you follow the steps below, running the software will be a breeze.
You should keep the Python source code and library files together.
My Sender program file is nrfsend.py, and all the related files are in the same directory.
Access Raspberry Pi's command prompt. Use the cd command to get to the directory containing the python script.
Navigate to the directory, type "sudo python3 your program.py," and hit enter to run the program. In less than a minute, you'll likely see nRf24's essentials laid out, and the broadcaster will begin broadcasting its bulletins at three-second intervals. Once the send is complete, the debug message will appear.
The Arduino UNO will now display the same code as the receiver.
The Arduino UNO can be programmed in a manner not dissimilar to that of the Raspberry Pi. Our procedures will be very similar; however, we'll use a different language for programming and other processes. The procedure will incorporate the nRF24l01 readout. Download the nRF24l01 Arduino library from GitHub. To get started, make sure all required libraries are installed. We're using a 16x2 I2C LCD, so we need to include the Wire.h library; the nRF24l01 communicates via SPI, so we also need the SPI library.
#include<SPI.h>
#include <Wire.h>
Don't forget to add the RF24 and LCD libraries so you may use them.
#include<RF24.h>
#include <LiquidCrystal_I2C.h>
Put the LCD's I2C address—27 in this case, as it's a 16x2 display—into the appropriate function.
LiquidCrystal_I2C lcd(0x27, 16, 2);
Pin 9 serves as the RF24's Common Emitter, and pin 10 serves as its Common Source Negative.
RF24 radio(9, 10) ;
Turn the radio on and tune in to channel 76. In addition, open the pipe for reading by setting the address to that of the Raspberry Pi.
radio.begin();
radio.setPALevel(RF24_PA_MAX) ;
radio.setChannel(0x76) ;
const uint64_t pipe = 0xE0E0F1F1E0LL ;
radio.openReadingPipe(1, pipe) ;
Start the I2C data transfer and initialize the LCD screen.
Wire.begin();
lcd.begin();
lcd.home();
lcd.print("Ready to Receive");
Turn on the radio's receiver and enter a message length of 32.
radio.startListening() ;
char receivedMessage[32] = {0}
The message will be read and saved immediately if a radio is connected. Display the message on the screen and send it to the serial monitor till the following message is received. Put the radio on hold while you tune in, then try again later. Right this way, in ten microseconds.
if (radio.available()) {
radio.read(receivedMessage, sizeof(receivedMessage));
Serial.println(receivedMessage) ;
Serial.println("Turning off the radio.") ;
radio.stopListening() ;
String stringMessage(receivedMessage) ;
lcd.clear();
delay(1000);
lcd.print(stringMessage);
}
Copy and paste the code below into your server and allow time for the response to arrive.
import RPi.GPIO as GPIO # import gpio
import time #import time library
import spidev
from lib_nrf24 import NRF24 #import NRF24 library
GPIO.setmode(GPIO.BCM) # set the gpio mode
# set the pipe address. This address should be entered on the receiver to
pipes = [[0xE0, 0xE0, 0xF1, 0xF1, 0xE0], [0xF1, 0xF1, 0xF0, 0xF0, 0xE0]]
radio = NRF24(GPIO, spidev.SpiDev()) # use the gpio pins
radio.begin(0, 25) # start the radio and set the ce,csn pin ce= GPIO08, csn= GPIO25
radio.setPayloadSize(32) #set the payload size as 32 bytes
radio.setChannel(0x76) # set the channel as 76 hex
radio.setDataRate(NRF24.BR_1MBPS) # set radio data rate
radio.setPALevel(NRF24.PA_MIN) # set PA level
radio.setAutoAck(True) # set acknowledgement as true
radio.enableDynamicPayloads()
radio.enableAckPayload()
radio.openWritingPipe(pipes[0]) # open the defined pipe for writing
radio.printDetails() # print basic detals of radio
sendMessage = list("Hi..Arduino UNO") #the message to be sent
while len(sendMessage) < 32:
sendMessage.append(0)
While True:
start = time.time() #start the time for checking delivery time
radio.write(sendMessage) # just write the message to radio
print("Sent the message: {}".format(sendMessage)) # print a message after succesfull send
radio.startListening() # Start listening the radio
while not radio.available(0):
time.sleep(1/100)
if time.time() - start > 2:
print("Timed out.") # print error message if the radio disconnected or not functioning anymore
break
radio.stopListening() # close radio
time.sleep(3) # give delay of 3 seconds
#include<SPI.h> // spi library for connecting nrf
#include <Wire.h> // i2c libary fro 16x2 lcd display
#include<RF24.h> // nrf library
#include <LiquidCrystal_I2C.h> // 16x2 lcd display library
LiquidCrystal_I2C lcd(0x27, 16, 2); // i2c address is 0x27
RF24 radio(9, 10) ; // ce, csn pins
void setup(void) {
while (!Serial) ;
Serial.begin(9600) ; // start serial monitor baud rate
Serial.println("Starting.. Setting Up.. Radio on..") ; // debug message
radio.begin(); // start radio at ce csn pin 9 and 10
radio.setPALevel(RF24_PA_MAX) ; // set power level
radio.setChannel(0x76) ; // set chanel at 76
const uint64_t pipe = 0xE0E0F1F1E0LL ; // pipe address same as sender i.e. raspberry pi
radio.openReadingPipe(1, pipe) ; // start reading pipe
radio.enableDynamicPayloads() ;
radio.powerUp() ;
Wire.begin(); //start i2c address
lcd.begin(); // start lcd
lcd.home();
lcd.print("Ready to Receive"); // print starting message on lcd
delay(2000);
lcd.clear();
}
void loop(void) {
radio.startListening() ; // start listening forever
char receivedMessage[32] = {0} ; // set incmng message for 32 bytes
if (radio.available()) { // check if message is coming
radio.read(receivedMessage, sizeof(receivedMessage)); // read the message and save
Serial.println(receivedMessage) ; // print message on serial monitor
Serial.println("Turning off the radio.") ; // print message on serial monitor
radio.stopListening() ; // stop listening radio
String stringMessage(receivedMessage) ; // change char to string
lcd.clear(); // clear screen for new message
delay(1000); // delay of 1 second
lcd.print(stringMessage); // print received mesage
}
delay(10);
}
The RF module's performance will be affected by the same factors as any other RF component. For instance, a transmitter's output power can be increased to extend the range of a transmission. However, this will cause a greater consumption of electricity by the transmitters (TX) device, reducing the useful life of battery-operated gadgets. Increasing the system's transmit power also makes it more vulnerable to interference from a second RF source.
Similarly, boosting the receiver's sensitivity increases the usable communication range but increases the risk of an error brought on by interference from other RF equipment. Matching antennas on both ends of a communication link can potentially boost the overall system's performance.
Finally, the regarded remote distance of any given system is typically measured in an open-air line-of-sight outline without any interference; nevertheless, problems such as floors, walls, and dense structures will frequently grasp the radio wave signals; thus, the actual operational distance will typically be less than specified.
The most common uses of radio frequency communication are in the areas of wireless data and voice transfer, home automation, and remote control, as well as in the industrial and commercial sectors.
RF-controlled switches can be used in home automation applications as an alternative to traditional switches. An RF remote allows one to operate lights and other electronics without leaving their current location. Those with mobility issues will benefit the most from this app. RF communication is helpful in industrial settings for directing autonomous robots and motorized vehicles. These robot vehicles are often employed in hazardous tasks humans cannot undertake. A data transmission unit is required to direct the motion of the robotic vehicles.
Multiple factors make radio frequency (RF) transmission preferable to infrared (IR) (infrared). The more extended range of RF signals makes them ideal for long-distance communications. Unlike radio frequency (RF), which can go across obstacles, infrared (IR) generally requires a clear path from transmitter to receiver. The reliability of RF transmission is far greater than that of infrared remote communications. While radio frequency (RF) communications require other IR-emitting devices that can disrupt a precise frequency range, infrared (IR) communications.
These are some of RF's drawbacks.
Preschoolers, expectant mothers, the elderly, those with pacemakers, little birds, flora, wildlife, insects, etc., are all negatively impacted by unregulated RF radiation.
More lightning has been seen in nearby cellular towers that use radio frequency than in other areas.
Some fruit crops in the vicinity of RF towers are also negatively impacted.
Because RF waves are accessible in both line-of-sight (LOS) and non-LOS zones of the transmitter, hackers can easily break into the system and decode sensitive personal or government data.
This problem can be avoided by employing highly protected methods like AES, WEP, WPA, etc., while transmitting data over radio frequency waves. Spread spectrum and frequency hopping modulation methods can also be applied to RF signals to prevent such eavesdropping.
This concludes the comprehensive instruction on wireless communication between a Raspberry Pi and an Arduino UNO via nRf24l01 modules. The 16 * 2 liquid crystal display will show the message. Pipe addresses are crucial on the Arduino UNO and the Raspberry Pi 4. In the following tutorial, we will learn how to Call and Text using Raspberry Pi and GSM Module in pi 4.
First, we will design a database for our website, then we will design the RFID circuit for scanning the student cards and displaying present students on the webpage, and finally, we will design the website that we will use to display the attendees of a class.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Breadboard | Amazon | Buy Now | |
| 2 | Jumper Wires | Amazon | Buy Now | |
| 3 | LCD 16x2 | Amazon | Buy Now | |
| 4 | LCD 16x2 | Amazon | Buy Now | |
| 5 | Raspberry Pi 4 | Amazon | Buy Now | |
Additionally, the Database server offers a DBMS that can be queried and connected to and can integrate with a wide range of platforms. High-volume production environments are no problem for this software. The server's connection, speed, and encryption make it a good choice for accessing the database.
There are clients and servers for MySQL. This system contains a SQL server with many threads that support a wide range of back ends, utility programs, and application programming interfaces.
We'll walk through the process of installing MySQL on the RPi in this part. The RFID kit's database resides on this server, and we'll utilize it to store the system's signed users.
There are a few steps before we can begin installing MySQL on a Raspberry Pi. There are two ways to accomplish this.
sudo apt update
sudo apt upgrade
Installing the server software is the next step.
Here's how to get MySQL running on the RPi using the command below:
sudo apt install MariaDB-server
Having installed MySQL on the Raspberry Pi, we'll need to protect it by creating a passcode for the "root" account.
If you don't specify a password for your MySQL server, you can access it without authentication.
Using this command, you may begin safeguarding MySQL.
sudo mysql_secure_installation
Follow the on-screen instructions to set a passcode for the root account and safeguard your MySQL database.
To ensure a more secured installation, select "Y" for all yes/no questions.
Remove elements that make it easy for anyone to access the database.
We may need that password to access the server and set up the database and user for applications like PHPMyAdmin.
For now, you can use this command if you wish to access the Rpi's MySQL server and begin making database modifications.
sudo MySQL –u root -p
To access MySQL, you'll need to enter the root user's password, which you created in Step 3.
Note: Typing text will not appear while typing, as it does in typical Linux password prompts.
Create, edit, and remove databases with MYSQL commands now available. Additionally, you can create, edit, and delete users from inside this interface and provide them access to various databases.
After typing "quit;" into MySQL's user interface, you can exit the command line by pressing the ESC key.
Pressing CTRL + D will also exit the MYSQL command line.
You may proceed to the next step now that you've successfully installed MySQL. In the next few sections, we'll discuss how to get the most out of our database.
The command prompt program MySQL must be restarted before we can proceed with creating a username and database on the RPi.
The MySQL command prompt can be accessed by typing the following command. After creating the "root" user, you will be asked for the password.
To get things started, run the command to create a MySQL database.
The code to create a database is "CREATE DATABASE", and then the name we like to give it.
This database would be referred to as "rfidcardsdb" in this example.
To get started, we'll need to create a MySQL user. The command below can be used to create this new user.
"rfidreader" and "password" will be the username and password for this example. Take care to change these when making your own.
create user “rfidreader" @localhost identified by "password."
We can now offer the user full access to the database after it has been built.
Thanks to this command, " "rfidreader" will now have access to all tables in our "rfidcardsdb" database.
grant all on rfidcardsdb.* to "rfidreader" identified by "password."
We have to flush the permission table to complete our database and user set up one last time. You cannot grant access to the database without flushing your privilege table.
The command below can be used to accomplish this.
Now we have our database configured, and now the next step is to set up our RFID circuit and begin authenticating users. Enter the “Exit” command to close the database configuration process.
An RFID reader reads the tag's data when a Rfid card is attached to a certain object. An RFID tag communicates with a reader via radio waves.
In theory, RFID is comparable to bar codes in that it uses radio frequency identification. While a reader's line of sight to the RFID tag is preferable, it is not required to be directly scanned by the reader. You can't read an RFID tag that is more than three feet away from the reader. To quickly scan a large number of objects, the RFID tech is used, and this makes it possible to identify a specific product rapidly and effortlessly, even if it is sandwiched between several other things.
There are major parts to Cards and tags: an IC that holds the unique identifier value and a copper wire that serves as the antenna:
Another coil of copper wire can be found inside the RFID card reader. When current passes through this coil, it generates a magnetic field. The magnetic flux from the reader creates a current within the wire coil whenever the card is swiped near the reader. This amount of current can power the inbuilt IC of the Card. The reader then reads the card's unique identifying number. For further processing, the card reader transmits the card's unique identification number to the controller or CPU, such as the Raspberry Pi.
Connect the reader to the Raspberry the following way:
use the code spi bcm2835 to see if it is displayed in the terminal.
lsmod | grep spi
SPI must be enabled in the setup for spi bcm2835 to appear (see above). Make sure that RPi is running the most recent software.
Make use of the python module.
sudo apt-get install python
The RFID RC522 can be interacted with using the Library SPI Py, found on your RPi.
cd ~
git clone https://github.com/lthiery/SPI-Py.git
cd ~/SPI-Py
sudo python setup.py install
cd ~
git clone https://github.com/pimylifeup/MFRC522-python.git
To test if the system is functioning correctly, let's write a small program:
cd ~/
sudo nano test.py
now copy the following the code into the editor
import RPi.GPIO as GPIO
import sys
sys.path.append('/home/pi/MFRC522-python')
from mfrc522 import SimpleMFRC522
reader = SimpleMFRC522()
print("Hold a tag near the reader")
try:
id, text = reader.read()
print(id)
print(text)
finally:
GPIO.cleanup()
Here we will write a short python code to register users whenever they swipe a new card on the RFID card reader. First, create a file named addcard.py.
copy the following code.
import pymysql
import cv2
from mfrc522 import SimpleMFRC522
import RPi.GPIO as GPIO
import drivers
display = drivers.Lcd()
display.lcd_display_string('Scan your', 1)
display.lcd_display_string('card', 2)
reader = SimpleMFRC522()
reader = SimpleMFRC522()
id, text = reader.read()
display = drivers.Lcd()
display.lcd_display_string('Type your name', 1)
display.lcd_display_string('in the terminal', 2)
user_id = input("user name?")
# put serial_no uppercase just in case
serial_no = '{}'.format(id)
# open an sql session
sql_con = pymysql.connect(host='localhost', user='rfidreader', passwd='password', db='rfidcardsdb')
sqlcursor = sql_con.cursor()
# first thing is to check if the card exist
sql_request = 'SELECT card_id,user_id,serial_no,valid FROM cardtbl WHERE serial_no = "' + serial_no + '"'
count = sqlcursor.execute(sql_request)
if count > 0:
print("Error! RFID card {} already in database".format(serial_no))
display = drivers.Lcd()
display.lcd_display_string('The card is', 1)
display.lcd_display_string('already registered', 2)
T = sqlcursor.fetchone()
print(T)
else:
sql_insert = 'INSERT INTO cardtbl (serial_no,user_id,valid) ' + \
'values("{}","{}","1")'.format(serial_no, user_id)
count = sqlcursor.execute(sql_insert)
if count > 0:
sql_con.commit()
# let's check it just in case
count = sqlcursor.execute(sql_request)
if count > 0:
print("RFID card {} inserted to database".format(serial_no))
T = sqlcursor.fetchone()
print(T)
display = drivers.Lcd()
display.lcd_display_string('Congratulations', 1)
display.lcd_display_string('You are registered', 2)
GPIO.cleanup()
The program starts by asking the user to scan the card.
Then it connects to the database using the pymysql.connect function.
If we enter our name successfully, the program inserts our details in the database, and a congratulations message is displayed to show that we are registered.
Using the LCD command library, you can:
sudo apt install git
cd /home/pi/
git clone https://github.com/the-raspberry-pi-guy/lcd.git
cd lcd/
sudo ./install.sh
After installation is complete, try running one of the program files
cd /home/pi/lcd/
Next, we will install the mfrc522 library, which the RFID card reader uses. This will enable us to read the card number for authentication. We will use:
Pip install mfrc522
Next, we will import the RPI.GPIO library enables us to utilize the raspberry pi pins to power the RFID card and the LCD screen.
Import RPi.GPIO
We will also import the drivers for our LCD screen. The LCD screen used here is the I2C 16 * 2 LCD.
Import drivers
Then we will import DateTime for logging the time the user has swiped the card into the system.
Import DateTime
In order to read the card using the rfid card, we will use the following code:
reader = SimpleMFRC522()
display = drivers.Lcd()
display.lcd_display_string('Hello Please', 1)
display.lcd_display_string('Scan Your ID', 2)
try:
id, text = reader.read()
print(id)
display.lcd_clear()
finally:
GPIO.cleanup()
The LCD is divided into two rows, 1 and 2. To display text in the first row, we use:
Display.lcd_display_string(“string”,1)
And 2 to display in the second row.
After scanning the card, we will connect to the database we created earlier and search whether the scanned card is in the database or not.
If the query is successful, we can display if the card is in the database; if not, we can proceed, then the user needs to register the card.
If the user is registered, the system saves the logs, the username and the time the card was swapped in a text file located in the/var/www/html root directory of the apache server.
Note that you will need to be a superuser to create the data.txt file in the apache root directory. For this, we will use the following command in the Html folder:
Sudo touch data.txt
Then we will have to change the access privileges of this data.txt file to use the program to write the log data. For this, we will use the following code:
Sudo chmod 777 –R data.txt
The next step will be to display this data on a webpage to simulate an online attendance register. The code for the RFID card can be found below.
#! /usr/bin/env python
# Import necessary libraries for communication and display use
import RPi.GPIO as GPIO
from mfrc522 import SimpleMFRC522
import pymysql
import drivers
import os
import numpy as np
import datetime
# read the card using the rfid card
reader = SimpleMFRC522()
display = drivers.Lcd()
display.lcd_display_string('Hello Please', 1)
display.lcd_display_string('Scan Your ID', 2)
try:
id, text = reader.read()
print(id)
display.lcd_clear()
# Load the driver and set it to "display"
# If you use something from the driver library use the "display." prefix first
try:
sql_con = pymysql.connect(host='localhost', user='rfidreader', passwd='password', db='rfidcardsdb')
sqlcursor = sql_con.cursor()
# first thing is to check if the card exist
cardnumber = '{}'.format(id)
sql_request = 'SELECT user_id FROM cardtbl WHERE serial_no = "' + cardnumber + '"'
now = datetime.datetime.now()
print("Current date and time: ")
print(str(now))
count = sqlcursor.execute(sql_request)
if count > 0:
print("already in database")
T = sqlcursor.fetchone()
print(T)
for i in T:
print(i)
file = open("/var/www/html/data.txt","a")
file.write(i +" Logged at "+ str(now) + "\n")
file.close()
display.lcd_display_string(i, 1)
display.lcd_display_string('Logged In', 2)
else:
display.lcd_clear()
display.lcd_display_string(“Please register”, 1)
display.lcd_display_string(cardnumber,2)
except KeyboardInterrupt:
# If there is a KeyboardInterrupt (when you press ctrl+c), exit the program and cleanup
print("Cleaning up!")
display.lcd_clear()
finally:
GPIO.cleanup()
Now we are going to design a simple website with Html that we are going to display the information of the attending students of a class, and to do this, we will have to install a local server in our raspberry pi.
Web, database, and mail servers all run on various server software. Each of these programs can access and utilize files located on a physical server.
A web server's main responsibility is to provide internet users access to various websites. It serves as a bridge between a server and a client machine to accomplish this. Each time a user makes a request, it retrieves data from the server and posts it to the web.
A web server's largest issue is to simultaneously serve many web users, each of whom requests a separate page.
For internet users, convert them to Html pages and offer them in the browser. Whenever you hear the term "webserver," consider the device in charge of ensuring successful communication in a network of computers.
Among its responsibilities is establishing a link between a server and a client's web browser (such as Chrome to send and receive data (client-server structure). As a result, the Apache software can be used on any platform, from Microsoft to Unix.
Visitors to your website, such as those who wish to view your homepage or "About Us" page, request files from your server via their browser, and Apache returns the required files in a response (text, images, etc.).
Using HTTP, the client and server exchange data with the Apache webserver, ensuring that the connection is safe and stable.
Because of its open-source foundation, Apache promotes a great deal of customization. As a result, web developers and end-users can customize the source code to fit the needs of their respective websites.
Additional server-side functionality can be enabled or disabled using Apache's numerous modules. Encryption, password authentication, and other capabilities are all available as Apache modules.
To begin, use the following code to upgrade the Pi package list.
sudo apt-get update
sudo apt-get upgrade
After that, set up the Apache2 package.
sudo apt install apache2 -y
That concludes our discussion. You can get your Raspberry Pi configured with a server in just two easy steps.
Type the code below to see if the server is up and functioning.
sudo service apache2 status
You can now verify that Apache is operating by entering your Raspberry Pi's IP address into an internet browser and seeing a simple page like this.
Use the following command in the console of your Raspberry Pi to discover your IP.
hostname-i
Only your home network and not the internet can access the server. You'll need to configure your router's port forwarding to allow this server to be accessed from any location. Our blog will not be discussing this topic.
The standard web page on the Raspberry Pi, as depicted above, is nothing more than an HTML file. First, we will generate our first Html document and develop a website.
Let's start by locating the Html document on the Raspbian system. You can do this by typing the following code in the command line.
cd /var/www/html
To see a complete listing of the items in this folder, run the following command.
ls -al
The root account possesses the index.html file; therefore, you'll see every file in the folder.
As a result, to make changes to this file, you must first change the file's ownership to your own. The username "pi" is indeed the default for the Raspberry Pi.
sudo chown pi: index.html
To view the changes you've made, all you have to do is reload your browser after saving the file.
Here, we'll begin to teach you the fundamentals of HTML.
To begin a new page, edit the index.html file and remove everything inside it using the command below.
sudo nano index.html
Alternatively, we can use a code editor to open the index.html file and edit it. We will use VS code editor that you can easily install in raspberry pi using the preferences then recommended software button.
You must first learn about HTML tags, which are a fundamental part of HTML. A web page's content can be formatted in various ways by using tags.
There are often two tags used for this purpose: the opening and closing tags. The material inside these tags behaves according to what these tags say.
The p> tag, for example, is used to add paragraphs of text to the website.
<p>The engineering projects</p>
Web pages can be made more user-friendly by using buttons, which can be activated anytime a user clicks on them.
<button>Manual Refresh</button>
<button>Sort By First Name</button>
<button>Sort By last Name</button>
A typical HTML document is organized as follows:
Let us create the page that we will use in this project.
<html>
<head>
</head>
<body>
<div id="pageDiv">
<p> The engineering projects</p>
<button type="button" id="refreshNames">Manual Refresh</button><br/>
<button type="button" id="firstSort">Sort By First Name</button><br/>
<button type="button" id="lastSort">Sort By Last Name</button>
<div id="namesFromFile">
</div>
</div>
</body>
</html>
<!DOCTYPE html>: HTML documents are identified by this tag. This does not necessitate the use of a closing tag.
<html>: This tag ensures that the material inside will meet all of the requirements for HTML. There is a /html> tag at the end of this.
</head>: It contains data about the website, but when you view it in a browser, you won't be able to see anything.
A metadata tag in the head tag can be used to set default character encoding in your website, for instance. This has a /head> tag at the end of it.
<head>
<meta charset="utf-8">
</head>
Also, you can have a title tag inside the head tag. This tag sets the title of your web page and has a closing </title> tag.
<head>
<meta charset="utf-8">
<title> My website </title>
</head>
<body>: The primary focus of the website page is included within this tag. Everything on a web page is usually contained within body tags once you've opened it. This has a /body> tag at the end of it. Many other tags can be found in this body tag, but we'll focus on the ones you need to get started with your first web page.
We will go ahead and style our webpage using CSS with the lines of codes below;
<head>
<!--
body {
width:100%;
background:#ccc;
color:#000;
text-align:left;
margin:0
;padding:10px
;font:16px/18pxArial;
}
button {
width:160px;
margin:0 0 10px;}
#pageDiv {
width:160px;
margin:20px auto;
padding:20px;
background:#ddd;
color:#000;
}
#namesFromFile {
margin:20px 0 0;
padding:10px;
background:#fff;
color:#000;
border:1px solid #000;
border-radius:10px;
}
-->
</style>
</head>
The style tags is a cascading style sheet syntax that lets developers style the webpages however they prefer.
You can add images to your web page by using the <img> tag. It is also a void element and doesn’t have a closing tag. It takes the following format
<img src="URL of image location">
For example, let’s add an image of the Seeeduino XIAO
<p>The Engineering projects</p>
<img src="https://www.theengineeringprojects.com/wp-content/uploads/2022/04/TEP-Logo.png">
Reload the browser to see the changes
This is the last step of this project, and we will implement a program that reads our data.txt file from the apache root directory and display it on the webpage that we designed. Since we already have our webpage up and running, we will use the javascript programming language to implement this function of displaying the log list on the webpage. All changes that we are about to implement will be done in the index.html file; therefore, open it in the visual studio code editor.
JavaScript is a dynamic computer programming language. It is lightweight and most commonly used as a part of web pages, whose implementations allow client-side scripts to interact with the user and make dynamic pages. It is an interpreted programming language with object-oriented capabilities.
One of the major strengths of JavaScript is that it does not require expensive development tools. You can start with a simple text editor such as Notepad.
Well, javascript as mentioned earlier is a very easy to use language that simply requires us to put the script tags inside the html tags.
<script> script program </script>
<header>
<script>
Here goes our javascript program
</script>
</header>
The javascript code first opens the data.txt file, then it reads all the contents form that file. Then it uses the xmlHttpRequest function to display the contents on the webpage. The buttons on the webpage activate different functions in the code.For instance manual refresh activates:
function refreshNamesFromFile(){
var namesNode=document.getElementById("namesFromFile");
while(namesNode.firstChild)
{ namesNode.removeChild(namesNode.firstChild);
}
getNameFile();
}
This function reads the content of the data.txt
The sort by buttons activate the sort function to sort the logged users either by first name or last name. The function that gets activated by these buttons is:
function sortByName(e)
{ var i=0, el, sortEl=[], namesNode=document.getElementById("namesFromFile"), sortMethod, evt, evtSrc, oP;
evt=e||event;
evtSrc=evt.target||evt.srcElement;
sortMethod=(evtSrc.id==="firstSort")?"first":"last";
while(el=namesNode.getElementsByTagName("P").item(i++)){
sortEl[i-1]=[el.innerHTML.split(" ")[0],el.innerHTML.split(" ")[1]];
}
sortEl.sort(function(a,b){
var x=a[0].toLowerCase(), y=b[0].toLowerCase(), s=a[1].toLowerCase(), t=b[1].toLowerCase();
if(sortMethod==="first"){
return x<y?-1:x>y?1:s<t?-1:s>t?1:0;
}
else{
return s<t?-1:s>t?1:x<y?-1:x>y?1:0;
}
});
while(namesNode.firstChild){
namesNode.removeChild(namesNode.firstChild);
}
for(i=0;i<sortEl.length;i++){
oP=document.createElement("P");
namesNode.appendChild(oP).appendChild(document.createTextNode(sortEl[i][0]+" "+sortEl[i][1]));
namesNode.appendChild(document.createTextNode("\r\n"));
//insert tests -> for style/format
if(sortEl[i][0]==="John"){
oP.style.color="#f00";
}
if(sortEl[i][0]==="Sue")
{ oP.style.color="#0c0";
oP.style.fontWeight="bold";
}
}
}
Automated attendance systems are excessively time-consuming and sophisticated in the current environment. It is possible to strengthen company ethics and work culture by using an effective smart attendance management system. Employees will only have to complete the registration process once, and images get saved in the system's database. The automated attendance system uses a computerized real-time image of a person's face to identify them. The database is updated frequently, and its findings are accurate in a user interactive state because each employee's presence is recorded.
Smart attendance systems have several advantages, including the following:
Students in elementary, secondary, and postsecondary institutions can utilize this system to keep track of their attendance. It can also keep track of workers' schedules in the workplace. Instead of using a traditional method, it uses RFID tags on ID cards to quickly and securely track each person.
1) Real-time tracking – Keeping track of staff attendance using mobile devices and desktops is possible.
2)Decreased errors – A computerized attendance system can provide reliable information with minimal human intervention, reducing the likelihood of human error and freeing up staff time.
3) Management of enormous data – It is possible to manage and organize enormous amounts of data precisely in the db.
4) Improve authentications and security – A smart system has been implemented to protect the privacy and security of the user's data.
5) Reports – Employee log-ins and log-outs can be tracked, attendance-based compensation calculated, the absent list may be viewed and required actions are taken, and employee personal information can be accessed.
This tutorial taught us to build a smart RFID card authentication project from scratch. We also learned how to set up an apache server and design a circuit for the RFID and the LCD screen. To increase your raspberry programming skills, you can proceed to building a more complex system with this code for example implementing face detection that automatically starts the authentication process once the student faces the camera or implement a student log out whenever the student leaves the system. In the following tutorial, we will learn how to build a smart security system using facial recognition.
Rather than investing in new electronic equipment, we will use an Arduino board and some basic components to measure the capacitance. To make this project, we should have some working knowledge about the capacitor. Here, we will not discuss the in-depth working of capacitors, but we will talk briefly so that it would be easy to understand the working principle of our project.
The capacitor is an electronic component that basically stores the energy when applied to an electric field. It has two parallel terminals connected by two parallel conducting plates separated by a dielectric material. Dielectric materials are electrical insulators(resist to pass the current) that can be polarised by applying an electric field. When we connect a battery with the capacitor then due to potential difference, the electric field is created between two oppositely charged plates of the capacitor and this way the capacitor stores the energy.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Capacitor | Amazon | Buy Now | |
| 2 | Resistor | Amazon | Buy Now | |
| 3 | LCD 16x2 | Amazon | Buy Now | |
| 4 | Arduino Uno | Amazon | Buy Now | |
To make this project, we will need some software to install. As we will make our project in the simulation, so for that we will install Proteus simulation software and for coding, we will use the Arduino IDE.
A brief about Proteus, it is a tool used for simulation and design of electronic circuits. Here we can design different types of electronic circuits and run the simulation. Although Proteus has a very big database for electronic components, still we need to install some libraries which we will use in this project.
You can download this whole project for example Proteus Simulation and Arduino Code, by tapping the below button:
Capacitance Measurement using ArduinoIn this project, we will use the following components-
Now let's talk about the working of this project. The capacitance of any capacitor is the amount of charge that is stored in that capacitor and its unit is Faraday (F). To measure the capacitance, we will use some basic properties of the capacitor.
So when we connect a power supply with a resistor across the terminals of a capacitor, it will take a certain amount of time to fully charge. And when we connect any discharging resistor as a load across it, then it will take a certain amount of time to fully discharge. And this charging and discharging time will be proportional to the capacitance of the capacitor and the charging resistor in the RC circuit.
We will use the time constant formula for the calculation of capacitance. The time constant of any capacitor is known as the time taken by the capacitor to charge 63 percent of applied voltage or the time taken by the capacitor to discharge to 33 percent of stored voltage.
Here,
T (Tau) = Time constant(Seconds)
R = Resistance (Ohms)
C= Capacitance (Farads)
Using the above principle, we will charge the capacitor using a resistor to reach the charge of the capacitor to 63 percent of applied voltage and we will measure the time taken by the capacitor to reach that point. As we know the resistor’s value and time constant, using these two, we can calculate the capacitance:
Note-Whenever uploading the code on the Arduino UNO, disconnect any wire which is connected to Rx(D0) and Tx(D1) pins, otherwise, it will give an error while uploading the code.
Now, we have a list of all the required components. Let's start connecting them.
While working on the real components, make sure you have connected the backlight of the LCD module and set the contrast properly otherwise nothing will be visible on the LCD module.
I hope we have covered all the points related to this project such as circuit diagrams, codes, and working simulation. And I think this will be a very useful project for your daily tinker life. Please let us know if you face any difficulties while making this project in the comment section below.
We will be happy to hear if you will make this project used in your projects.
Thanks for reading this article. All the best and see you in the next project.
We all use calculators in our daily life, whether you are working in an office or counting money at the bank, you are buying your daily grocery or doing shopping online, you will find calculators in different forms everywhere. In fact, the computer was initially considered a giant calculator. So if it is that common, why do we not make our own calculator?
Before going into the details of the project, it is good to know some history of that, let’s know some facts about the calculator. So the first known device for calculation is Abacus. And the first digital calculator was made by Texas Instruments in 1967 before that all calculators were mostly mechanical and they did not need any electronic circuits. The first all-transistor calculator was made by IBM and it is claimed that the calculator performed all the four basic operations such as addition, subtraction, multiplication, and division.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Keypad 4x4 | Amazon | Buy Now | |
| 2 | LCD 16x2 | Amazon | Buy Now | |
| 3 | Arduino Mega 2560 | Amazon | Buy Now | |
In this, we will be going to use the Proteus simulation tool and we will make our whole project using this software only. But no need to worry while using the actual components because if our project works perfectly with simulation, it will definitely work with actual hardware implementation. And the best part of the simulation is, here we will not damage any components by making any inappropriate connections.
If you don’t have an idea about Proteus, Proteus is a software for the simulation of electronic circuits and here we can use different types of microcontrollers and run our applications on them.
So for this project, we need to install this software. This software has a big database for all electronics components but still, it lacks some, therefore we have to install some libraries for modules which we are going to use in this project.
In this project, we will take input from the user using a keypad and perform the operation using Arduino UNO and display the result on an LCD display.
Our project will work the same as a normal digital calculator such that the user will enter two numerical values and select arithmetic operations which she/he wants to perform on the given values. Once the user clicks on the equal button, thereafter Arduino UNO will calculate the output and display the result on the LCD module.
Now, let’s start designing our circuit diagram for the calculator.
Now we have all the required components in the workplace as follows.
Let's start connecting them.
That is all for connection. Make sure all the connections are correct, especially for keypad’s row and column connections otherwise we will get the wrong values from the keypad input.
And while working on the actual components, power the backlight of the LCD module and set the appropriate contrast, else nothing will be visible even if that has been displayed.
In the above-mentioned image, the first argument for RS pin, second for Enable pin, and rest four for data pins.
And required operation will be stored in the ‘op’ variable and a flag will be set for taking the second number.
That is all the code, we need to run an Arduino Calculator.
Now, we have completed the coding and circuit part, it is time to run the simulation in the Proteus.
I hope we have covered everything related to Arduino calculator i.e. Simulation, Code, Working etc. but still if you find anything confusing, ask in the comments.
Thanks for reading this project out. All the best for your projects!
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | LEDs | Amazon | Buy Now | |
| 2 | Resistor | Amazon | Buy Now | |
| 3 | LCD 16x2 | Amazon | Buy Now | |
| 4 | Arduino Mega 2560 | Amazon | Buy Now | |
As you all already know the importance of traffic lights and their usage has solved a number of traffic problems, traffic is becoming denser on each road in the whole world by the hour. This leads us to consider traffic density at such roads as well. A number of different solutions have been developed in recent times to help with this problem such as roundabouts. This is done so to ensure the safety of vehicles on road and of people walking on pedestrian walks. With the world going towards automation and autonomous systems, this is the right time to switch traffic lights to an autonomous traffic light system too and make the system intelligent.
We will be going through how to make an autonomous traffic system by using Arduino as a microcontroller. However, we’re not making an actual system rather we will be making a simulation of the said traffic system on a circuit simulating software Proteus. So make sure you already have the latest version of Proteus installed on your PCs and laptops. If not, you should first install the Proteus Software by following the embedded link. Proteus is open database software, meaning people can easily make their own circuit simulating libraries for the software and can easily integrate those libraries. This helps in making the software versatile and easy to use. You can easily add your own components or download libraries of components and place them within the software.
To start working with this project, you need to install and include the following libraries on your Proteus software:
This is a smart 4-way traffic light system. The pedestrian lights work such that whenever a certain traffic light is green its opposite pedestrian lights turn on. An addition of ultrasonic sensors have been made in the traffic light sequence. One ultrasonic sensor is placed at each traffic light. Each ultrasonic sensor controls the time of their respective green traffic light. When the ultrasonic sensor output is high, the traffic light opens for one second, when the ultrasonic sensor output is intermediate the traffic light opens for two seconds and when the ultrasonic sensor output is low the traffic lights open for 3 seconds.
The main components and their use in this project is given below:
We will go through the details of some of the important components being used in this project.
Arduino is an open-source programmable board that serves as a microcontroller and processes information based upon inputs and gives information to actuators in terms of output. Arduino Mega is based upon the chip ATmegaGA2560 and has 53 digital I/O pins.
Liquid Crystal Displays used in electronics are of two basic sizes, 16x2 and 24x2. These represent the number of columns and rows of the LCD. Each pixel can store one character in it. It is also known as a character LCD. It comes equipped with a backlight. The intensity or glow of the backlight can be controlled by attaching a potentiometer at specified pins.
Figure 2: LCD display
An ultrasonic sensor uses SONAR technology to identify objects. It is basically used to find the distance of objects from the sensor. The ultrasonic sensor works by sending out ultrasonic waves and when these waves or parts of waves hit an object, they are reflected backward and the time from their propagation to their return is then noted. This time is then converted into the distance because we already know the speed by which those waves are traveling.
Figure 3: Ultrasonic Sensor
In order to simulate this project on Proteus software, we will first make the circuit diagram on Proteus. After that, we will write our code on Arduino IDE software and integrate it with the circuit made in Proteus.
Open Proteus and open a new project. Import the following components in your Proteus worksheet.
Place the component in your worksheet as illustrated in the figure below:
Figure 5: Placement of components
After placing the components, make the connections as follows:
With this, your circuit connections are complete and we will now move on to the firmware setup of this circuit.
We have divided the Arduino code in 3 segments:
We will look at these sections separately now.
The first step in the code is the declaration of variables that we will utilize in our program. At first is the declaration of ultrasonic sensor pins and setting them up with their respective pins of Arduino board. The syntax of this code is as follows.
Figure 6: Ultrasonic declaration code
Now we will include the library of LCD into our Arduino program, you can download this library from within the software. After that we will declare the LCD by defining the LCD pins. The syntax for which is as follows:
In the next step, we will declare traffic light variables and define their Arduino pins.
Figure 8: Traffic light variable declaration
Now, we will declare the variables of pedestrian LEDs and then allot them their Arduino pins being used in the circuit.
Figure 9: Declaration of pedestrian LEDs
Now, there are two variables being used for each ultrasonic sensor for the calculation of their distance and time duration. We will declare those variables now.
Figure 10: Declaration of variables being used for calculations
Void setup is the part of Arduino program that only runs once, in this section the program that only needs to run once is put, such as declaring pins as output pins or input pins.
Only the echo pins of ultrasonic sensor are input pins while all other pins are going to be output pins for this project.
We will first set up ultrasonic pins as follows:
Now we will declare traffic light pins as output pins. The syntax for this is given as follows:
Figure 12: Setup of Traffic light Pins as Output
Now we will setup our pedestrian LEDs.
Figure 13: Setup of Pedestrian LEDs as Output
Now we will initialize our LCD, this basically tells the microcontroller to start the LCD and give power to it. The syntax is given below.
Figure 14: Initializing LCD
This part of Arduino Program runs in a loop and consists of the main code of the program in which all the calculations are being done.
In the first part of the program, we will set the trigger pin of the first ultrasonic sensor to low and high. This would generate a pulse and send out a wave. After that we will read a pulse input from the echo pin. This will give us the duration in which the wave was propagated and returned. After that we will calculate the distance from the duration of the wave.
Figure 15: Syntax of 1st Ultrasonic Sensor
This distance calculation is for our first traffic light. Now we will use the if loop to check our distance value.
If the value falls between our set limit for the loop, the signal will turn green for three seconds. This will also be displayed on the LCD.
Figure 17: Arduino Code
After that in our if loop, the yellow lights 1 and 2 will turn on to indicate transition.
Figure 18: Arduino Code
Now we will use the if loop to check our distance value.
If the value falls between our set limit for the loop of intermediate traffic, the signal will turn green for two seconds. This will also be displayed on the LCD.
Figure 19: Arduino Code
After that in our if loop, the yellow lights 1 and 2 will turn on to indicate transition.
Now we will use the if loop to check our distance value again.
If the value falls between our set limit for the loop of low traffic, the signal will turn green for one second. This will also be displayed on the LCD.
Figure 21: Arduino Code
After that in our if loop, the yellow lights 1 and 2 will turn on to indicate transition.
Figure 22: Arduino Code
Now we will set the trigger pin of the second ultrasonic sensor to low and high. This would generate a pulse and send out a wave. After that we will read a pulse input from the echo pin. This will give us the duration in which the wave was propagated and returned. After that we will calculate the distance from the duration of the wave.
Figure 23: Arduino Code
This distance calculation is for our Second traffic light. Now we will use the if loop to check our distance value.
Figure 24: Arduino Code
If the value falls between our set limit for the loop, the signal will turn green for three seconds. This will also be displayed on the LCD.
After that in our if loop, the yellow lights 2 and 3 will turn on to indicate transition.
Figure 26: Arduino Code
Now we will use the if loop to check our distance value.
If the value falls between our set limit for the loop of intermediate traffic, the signal will turn green for two seconds. This will also be displayed on the LCD.
Figure 27: Arduino Code
After that in our if loop, the yellow lights 2 and 3 will turn on to indicate transition.
Figure 28: Arduino Code
Now we will use the if loop to check our distance value again.
If the value falls between our set limit for the loop of low traffic, the signal will turn green for one second. This will also be displayed on the LCD.
Figure 29: Arduino Code
After that in our if loop, the yellow lights 2 and 3 will turn on to indicate transition.
Now we will set the trigger pin of the third ultrasonic sensor to low and high. This would generate a pulse and send out a wave. After that, we will read a pulse input from the echo pin. This will give us the duration in which the wave was propagated and returned. After that we will calculate the distance from the duration of the wave.
Figure 31: Arduino Code
This distance calculation is for our third traffic light. Now we will use the if loop to check our distance value.
Figure 32: Arduino Code
If the value falls between our set limit for the loop, the signal will turn green for three seconds. This will also be displayed on the LCD.
Figure 33: Arduino Code
After that in our if loop, the yellow lights 3 and 4 will turn on to indicate transition.
Figure 34: Arduino Code
Now we will use the if loop to check our distance value.
If the value falls between our set limit for the loop of intermediate traffic, the signal will turn green for two seconds. This will also be displayed on the LCD.
After that in our if loop, the yellow lights 3 and 4 will turn on to indicate transition.
Figure 36: Arduino Code
Now we will use the if loop to check our distance value again.
If the value falls between our set limit for the loop of low traffic, the signal will turn green for one second. This will also be displayed on the LCD.
Figure 37: Arduino Code
After that in our if loop, the yellow lights 3 and 4 will turn on to indicate transition.
Figure 38: Arduino Code
Now we will set the trigger pin of the fourth ultrasonic sensor to low and high. This would generate a pulse and send out a wave. After that, we will read a pulse input from the echo pin. This will give us the duration in which the wave was propagated and returned. After that, we will calculate the distance from the duration of the wave.
Figure 39: Arduino Code
This distance calculation is for our fourth traffic light. Now we will use the if loop to check our distance value.
If the value falls between our set limit for the loop, the signal will turn green for three seconds. This will also be displayed on the LCD.
Figure 41: Arduino Code
After that in our if loop, the yellow lights 4 and 1 will turn on to indicate transition.
Figure 42: Arduino Code
Now we will use the if loop to check our distance value.
If the value falls between our set limit for the loop of intermediate traffic, the signal will turn green for two seconds. This will also be displayed on the LCD.
After that in our if loop, the yellow lights 4 and 1 will turn on to indicate transition.
Figure 44: Arduino Code
Now we will use the if loop to check our distance value again.
If the value falls between our set limit for the loop of low traffic, the signal will turn green for one second. This will also be displayed on the LCD.
Figure 45: Arduino Code
After that in our if loop, the yellow lights 4 and 1 will turn on to indicate transition.
Figure 46: Arduino Code
At first, after writing the code, generate its hex file and put that hex file on the Arduino board on your Proteus software. After that, run the simulation. The results of the simulation are shown below thoroughly.
At first, when sensor one gives the output within 500 cm, the traffic light will turn on for one second only.
Figure 47: Simulation Results
However, if the sensor one value is between 500 and 900 cm, the traffic light 1 will be green for 2 seconds with the LCD displaying the remaining time.
Figure 48: Simulation Results
If the sensor values are above 900 cm, then the lights will be green for 3 seconds.
When the sensor two gives the output within 500 cm, traffic light 2 will turn on for one second only.
Figure 50: Simulation Results
However, if the sensor two value is between 500 and 900 cm, the traffic light 2 will be green for 2 seconds with the LCD displaying the remaining time.
Figure 51: Simulation Results
If the sensor values are above 900 cm, then the lights will be green for 3 seconds.
Figure 52: Simulation Results
When sensor three gives the output within 500 cm, traffic light 3 will turn on for one second only.
However, if the sensor three value is between 500 and 900 cm, the traffic light 3 will be green for 2 seconds with the LCD displaying the remaining time.
Figure 54: Simulation Results
If the sensor values are above 900 cm, then the lights will be green for 3 seconds.
Figure 55: Simulation Results
When sensor four gives the output within 500 cm, traffic light 4 will turn on for one second only.
Figure 56: Simulation Results
However, if the sensor four value is between 500 and 900 cm, the traffic light 4 will be green for 2 seconds with the LCD displaying the remaining time.
Figure 57: Simulation Results
If the sensor values are above 900 cm, then the lights will be green for 3 seconds.
Figure 58: Simulation Results
Phew! I know that this was an extremely long project, but that is a part of an engineer’s life. Multiple receptions and running recurring patterns smoothly requires skill and patience only an engineer can possess. I hope you guys made it through. Kudos to your nerves of steel. Thanks for reading.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | LCD 16x2 | Amazon | Buy Now | |
| 2 | DHT11 | Amazon | Buy Now | |
| 3 | Arduino Uno | Amazon | Buy Now | |
#include<dht.h>// DHT11 humidity sensor library
#include<LiquidCrystal.h> //LCD library
dht DHT; //Creating sensor object
#define DHT11_PIN A3 // Sensor is connected to Arduino pin 3
LiquidCrystal lcd(8, 9, 10, 11, 12, 13);// LCD connected with Arduino on these pins
void setup()
{
Serial.begin(9600); //setting baud rate
Serial.println(" =====================================================");
Serial.println(" || Welcome to Temperarue and Humidity Detector ||");
Serial.println(" =====================================================");
Serial.println("");
lcd.begin(20, 4); // initialinzing the LCD order
lcd.setCursor(4,1); //Setting the cursor on LCD
lcd.print("Welcome to");//printing on LCD
lcd.setCursor(2,2);
lcd.print("Humidity detector");
delay(2000);//adding delay of 2 secons or 2000 msec
}
void loop()//method used to run the code repeatedly
{
int chk = DHT.read11(DHT11_PIN); //Reading data from sensor
Serial.print(" Humidity = ");//prints on the serial monitor
Serial.print(DHT.humidity);// prints obtained humidity on serial port
Serial.print(" g/m^3");
lcd.clear();//clears all the data on LCD
delay(1000);//adding delay of 1 second
lcd.display(); //starting the display of LCD after clearing
lcd.setCursor(0,0);
lcd.print("Humidity=");
lcd.print(DHT.humidity);
lcd.print(" g/m^3");
Serial.print(" \tTemperature = ");//prints on the serial monitor
Serial.print(DHT.temperature, 1);//prints obtained temperature on serial port
Serial.println(" degrees");
lcd.setCursor(0,1);
lcd.print("Temperature=");//prints on LCD
lcd.print(DHT.temperature, 1);//prints the obtained temperature on LCD
lcd.print(" deg");
lcd.setCursor(1,2);
lcd.print("www.TheEngineering");
lcd.setCursor(4,3);
lcd.print("Projects.com");
delay(2000);//adding the delay of 2 seconds
}
Hello friends, I hope you all are doing great. In today’s tutorial, we will have a look at Introduction to 16x2 LCD Module. LCD stands for liquid crystal display it is mostly used in different electronic projects and devices to display different values. LCD uses liquid crystals for the generation of visible images. 16 x 2 liquid crystal display is a basic LCD module used in DIY electronic projects and circuits. In this LCD module, there are two rows every row consists of sixteen numbers.
With the two rows in this module, there are sixteen columns. The VA dimensions of these modules are (66 x 16) millimeters and the thickness is 13.2 millimeters. Its operating voltage is plus five or plus three volts. In today's post, we will have a look at working, applications, circuits, features, advantages and disadvantages. So let's get started with Introduction to 16x2 LCD Module.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | LCD 16x2 | Amazon | Buy Now | |
| Pin No: | Pin Name: | Parameters |
| Pin#1 | Ground | This pin is used to connect the ground. |
| Pin#2 | +5 Volt | At this pinout plus five volts are applied to on the LCD. |
| Pin#3 | VE | This pin used to select the contract of the display. |
| Pin#4 | Register Select | This pinout is used to MCU controller connected led to a shift from command to data mode. |
| Pin#5 | Read and Write | It used for reading and wiring of data. |
| Pin#6 | Enable | It linked with the MCU to toggle among zero and one. |
| Pin#7 | Data Pin 0 | The pinouts from zero to seven are data pinouts and these are linked with the MCU for transmission of data. This liquid crystal module can also operate on the four-bit mode by working on o, 1, 2, and 3 pinouts and others are free. |
| Pin#8 | Data Pin 1 | |
| Pin#9 | Data Pin 2 | |
| Pin#10 | Data Pin 3 | |
| Pin#11 | Data Pin 4 | |
| Pin#12 | Data Pin 5 | |
| Pin#13 | Data Pin 6 | |
| Pin#14 | Data Pin 7 | |
| Pin#15 | LED Positive | This pinout is for turn backlight of led into positive. |
| Pin#16 | LED Negative | Backlight liquid crystal display pinout negative terminal. |
| Sr.No | Hex Code | Parameters |
| 1 | 1 | This command will remove data displaying on the screen of lcd. |
| 2 | 2 | It used to move back home. |
| 3 | 4 | It used to change location of a cursor to left side. |
| 4 | 6 | It changes the position of cursor to right side. |
| 5 | 5 | It used for shift display on right. |
| 6 | 7 | It used for Shift display one left |
| 7 | 8 | It used to off the display and cursor will also off. |
| 8 | 0A | It used for both display off, a cursor on. |
| 9 | 0C | It used for display on, cursor also off. |
| 10 | 0E | By using this command we can on display, the cursor will be blinking |
| 11 | 0F | By this command Display will be on, the cursor also blinking. |
| 12 | 10 | It changes the location of a cursor to left. |
| 13 | 14 | It set cursor location to right. |
| 14 | 18 | It changes the location of the complete display to the left side. |
| 15 | 1C | It changes the location of the complete display to right side. |
| 16 | 80 | It used to move the cursor to the first line. |
| 17 | C0 | It send the cursor to starting of the second line. |
| 18 | 38 | 2 lines and 5×7 matrix. |
So it is the detailed article on the 16x2 LCD Module if you have any question about ask in comments. Thanks for reading.