Project Files of Raspberry Pi 3 Model B Library for Proteus: WiFi Sensor Station

RASPBERRY PI 3 MODEL B LIBRARY FOR PROTEUS - V1.0 (BCM2837 QUAD CORE, 1 GB, WI-FI + BLUETOOTH, 40-PIN HEADER, ETHERNET)
YOUR PYTHON PROGRAM RUNS ON THE BOARD - DEMO: A WI-FI AIR STATION (PMS5003 UART, AHT20 I2C, FAN RELAY, PHONE + LAPTOP)
Designed by The Engineering Projects www.TheEngineeringProjects.com

IMPORTANT LINKS
Article (read it first - pictures, step by step, every feature explained):
  https://www.theengineeringprojects.com/2026/10/raspberry-pi-3-model-b-library-for-proteus.html
Report a bug or suggest a feature (our forum):
  https://www.theengineeringprojects.com/forum/category/raspberry-pi-3-model-b-proteus-library
The demo's parts are our libraries (included) - their articles:
  PMS5003:  https://www.theengineeringprojects.com/2026/10/pms5003-particle-sensor-library-for-proteus-v1-0.html
  AHT20:    https://www.theengineeringprojects.com/2026/10/aht20-sensor-library-for-proteus-v1-0.html
  Relay:    https://www.theengineeringprojects.com/2026/10/relay-module-library-for-proteus-v1-0.html
  Laptop:   https://www.theengineeringprojects.com/2026/10/laptop-wifi-monitor-library-for-proteus.html
  Phone:    https://www.theengineeringprojects.com/2026/10/mobile-wifi-monitor-library-for-proteus.html
The earlier boards of this series:
  https://www.theengineeringprojects.com/2026/10/raspberry-pi-model-b-library-for-proteus.html
  https://www.theengineeringprojects.com/2026/10/raspberry-pi-1-model-b-plus-library-for-proteus.html
  https://www.theengineeringprojects.com/2026/10/raspberry-pi-2-model-b-library-for-proteus.html
Support us (the libraries are free):
  https://www.theengineeringprojects.com/donate

FILE STRUCTURE
Raspberry-Pi-3-Model-B-TEP-v1.0/
|-- Proteus Library Files/
|   |-- TEPAHT20.LIB                                     96.9 KB   AHT20 (demo), to LIBRARY
|   |-- TEPLAPTOP.LIB                                    39.5 KB   the laptop (demo), to LIBRARY
|   |-- TEPMOBILE.LIB                                    13.1 KB   the phone (demo), to LIBRARY
|   |-- TEPPMS5003.LIB                                   71.0 KB   PMS5003 (demo), to LIBRARY
|   |-- TEPRELAY.LIB                                    490.4 KB   the relay (demo), to LIBRARY
|   |-- TEPRPI3B.LIB                                     56.0 KB   the Raspberry Pi 3 Model B, to LIBRARY
|-- Proteus Model Files/
|   |-- TEPAHT20.DLL                                    336.5 KB   AHT20, to MODELS
|   |-- TEPNET.DLL                                       2.37 MB   the Pi + monitors + network, to MODELS
|   |-- TEPPMS5003.DLL                                  297.5 KB   PMS5003, to MODELS
|   |-- TEPRELAY.DLL                                    330.0 KB   the relay, to MODELS
|   |-- TEPPi/python/                                   17.54 MB   Python 3.11.9 embeddable (33 files)
|   |-- TEPPi/runtime/                                  856.3 KB   TEP Pi runtime, gpiozero (61 files)
|-- Python Code/
|   |-- air_station.py                                    4.8 KB   the demo
|   |-- blink.py                                          0.3 KB   an LED on GPIO17 (the default)
|-- Proteus Simulation/
|   |-- air_station.py                                    4.8 KB   the program of the demo
|   |-- Pi-3-Model-B-WiFi-Air-Station.pdsprj             32.9 KB   the demo: Wi-Fi air station
|   |-- TEPAHT20.DLL                                    336.5 KB   copy of the model
|   |-- TEPNET.DLL                                       2.37 MB   copy of the model
|   |-- TEPPMS5003.DLL                                  297.5 KB   copy of the model
|   |-- TEPRELAY.DLL                                    330.0 KB   copy of the model
|-- README.txt                                          ~18.0 KB   this file
Total: 25.81 MB (unzipped). The source code of the models and of the TEP Pi runtime is not included.

WHAT IS IT?
The Raspberry Pi 3 Model B (V1.2, 2016) as one Proteus part - and a way to run Raspberry Pi programs in Proteus 8.5.
Proteus cannot run Raspberry Pi OS, so this library does not emulate Linux. It does what matters for electronics: the
board runs YOUR PYTHON PROGRAM (a .py file, the PROGRAM property) against the circuit on the sheet, with the Python
libraries a Pi uses for its pins - and, new on this board, its Wi-Fi.
  * At Run the board starts Python 3.11 (included: the TEPPi folder) with our TEP Pi runtime, then your program.
    The program and Proteus work in lockstep: while the program runs, Proteus waits; while the program sleeps, waits
    for a pin, a bus or the network, Proteus runs. So time.sleep(0.5) is 0.5 s of simulation, a busy loop still moves
    the clock (about 3 us per GPIO call, as Python on the Pi 3's 1.2 GHz Cortex-A53), and every edge is on time.
    time.time(), time.strftime() and datetime.now() follow the simulation's clock too.
  * Wi-Fi: wlan0 joins the network in the WIFISSID / WIFIPASS properties (default: our router "TEP-WiFi", password
    12345678 - the network of our ESP32 / Arduino Wi-Fi parts and the Laptop / Mobile WiFi Monitors) as Raspberry Pi
    OS does at boot: 2.3 to 3.5 s after Run the Pi has 192.168.1.51 (192.168.1.(50 + the part's number)), the name
    raspberrypi.local. One network interface at a time: wlan0 while the Ethernet cable is out (ETHERNET OUT, the
    default here), eth0 when the cable is in at Run (ETHERNET IN).
  * Threads work (gpiozero's threads, your own threading.Thread, Timer, Queue): every wait is in simulation time; an
    error in a thread is printed as Python prints it ("Exception in thread ...").
  * The Python libraries for the pins (the same names, numbers and messages as on a Pi):
      RPi.GPIO      setmode, setup, output, input, cleanup, add_event_detect / event_detected / wait_for_edge with
                    callbacks and bouncetime, PWM (software PWM made by the board, steady while the program sleeps)
      gpiozero      LED, PWMLED, Button, OutputDevice, Buzzer, Servo, MotionSensor, DistanceSensor, CPUTemperature
                    and the rest (gpiozero 2.0.1, unchanged, on RPi.GPIO)
      serial        pyserial on /dev/serial0 (on a Pi 3 = /dev/ttyS0, the mini UART - the other UART serves Bluetooth;
                    /dev/ttyAMA0 is accepted too): TXD GPIO14, RXD GPIO15, any baud rate, timeouts, back-to-back
                    bytes (a sensor's 32-byte frames)
      smbus2 / smbus  I2C bus 1 on GPIO2 (SDA) / GPIO3 (SCL) at 100 kHz, the Pi's 1.8 k pull-ups: read_byte,
                    write_byte, the byte / block reads and writes, write_quick, i2c_rdwr with i2c_msg; a device that
                    does not answer gives OSError [Errno 121] Remote I/O error
      spidev        SPI0 on GPIO11 (SCLK), GPIO10 (MOSI), GPIO9 (MISO), CE0 = GPIO8, CE1 = GPIO7, modes 0 to 3, up to
                    8 MHz; xfer / xfer2 take up to 4096 bytes (spidev's bufsiz), writebytes2 any length
      1-Wire        the DS18B20's files under /sys/bus/w1/devices (w1-gpio on GPIO4), as the kernel makes them
      Adafruit_DHT, adafruit_dht + board   DHT11 / DHT22 on any GPIO
      socket        TCP and UDP on wlan0 or eth0, http.server / socketserver, urllib.request, select
  * The Pi's own files: /proc/cpuinfo (Revision a02082, four ARMv8 processors), /proc/device-tree/model ("Raspberry Pi
    3 Model B Rev 1.2"), the CPU temperature in /sys/class/thermal (gpiozero's CPUTemperature), /proc/loadavg,
    /proc/meminfo (1 GB).
  * The Pi Terminal (our TEP window, no Windows title bar): the shell prompt (pi@raspberrypi:~ $ python3 ...), the
    program's output (OUT) and errors (ERR, as Python prints them on a Pi), a line for input() (IN); its Board tab
    shows the GPIOs (BCM numbers), the LEDs, the supply pins and RESTART PROGRAM. Click the HDMI socket or the
    processor to open it.
  * The LEDs: PWR (red) and ACT (green: it flickers while the board boots and when the program prints) standing at the
    left edge above the micro-USB, and the RJ45 jack's own LEDs - LNK (green) and 100 (yellow), lit with the cable in.
  * The header's supply pins power the modules wired to them, as on the bench: 5V, 3V3 and GND as logic levels (an
    analog VCC reading sees 5 V on either rail).
The board is drawn our way at its real size (85 x 56 mm, rounded corners, four mounting holes) from the Raspberry Pi 3
Model B drawing: the 40-pin header along the top edge, the white Wi-Fi / Bluetooth chip antenna on the left edge under
pin 1, the DSI display connector with the microSD card under it, PWR / ACT at the left edge above the micro-USB, the RUN
pads beside the top-right mounting hole, the BCM2837 (BROADCOM BCM2837RIFBG - the 1 GB RAM is on the underside, as on
the real board), the SMSC LAN9514, the two stacked USB pairs and the RJ45 on the right, the micro-USB power socket,
HDMI, the CSI camera connector and the black 4-pole A/V jack along the bottom. The 40 pins leave the top edge as one
comb 50 thou apart, each with a colour-coded tag: 5V red, 3V3 orange, GND black, GPIO green, I2C blue, SPI pink, UART
purple, ID_SD / ID_SC grey.

ONE DEVICE (search "RASPBERRY" in Pick Devices):
  RASPBERRY PI 3 MODEL B   "Raspberry Pi 3 Model B" V1.0 (category Microprocessor ICs > Raspberry Pi), prefix PI,
                           model TEPNET.DLL (with the TEPPi folder)
The same TEPNET.DLL also runs our Raspberry Pi Model B, 1 Model B+ and 2 Model B, our Ethernet and Wi-Fi shields,
modules and boards and the Laptop / Mobile WiFi Monitors; it replaces any older TEPNET.DLL (keep only this newest one
in MODELS).

TEST STATUS
V1.0: verified in Proteus 8.5 on 24 Oct 2026 with the demo project as shipped. What the Proteus runs showed:
* Pi-3-Model-B-WiFi-Air-Station: wlan0 joins TEP-WiFi and the program prints "serving on http://192.168.1.51:8000/"
  at 2.5 s of simulation; then a line with each PMS5003 frame - PM1.0 / PM2.5 / PM10 1 / 1 / 1 ug/m3 while the
  sensor's fan settles, 24.0 C and 50.0 % from the AHT20, "fan OFF (AUTO)".
* The Laptop WiFi Monitor (192.168.1.21) and the Mobile WiFi Monitor (192.168.1.41) open http://192.168.1.51:8000/
  (Browser, Go): HTTP 200, the readings, FAN ON / FAN OFF / AUTO.
* SMOKE in the PMS5003's pop-up (fast mode: frames 0.2 to 0.8 s apart): PM2.5 34, 68 ug/m3 - over 35, AUTO switches
  the fan's relay on ("fan ON (AUTO)"): RLY1 pulls in, K1 ON in its pop-up, NO closed, D1 lit; the phone's page says
  Fan: ON (AUTO).
* FAN OFF on the phone's page: the terminal prints "the page: /fan/off - fan OFF (MANUAL)", the relay drops out, D1
  goes dark, and the fan stays off in MANUAL while PM2.5 climbs to 284 ug/m3. After 30 s the PMS5003's fan has
  settled and the frames come every 2.3 s again.
* The Board tab: GPIO14 HIGH (TXD idle), GPIO15 HIGH (the PMS5003's TX idle), GPIO2 / GPIO3 with the Pi's pull-ups,
  GPIO17 HIGH with the fan off (LOW while it is on); PWR lit, LNK / 100 dark (no cable).
* Speed on our test PC: about 5 to 15 % of real time with the five pop-ups and both pages open.

INSTALLATION (about 3 minutes)
1. Close Proteus. Extract the WHOLE ZIP to a normal folder (e.g. Desktop).
2. Copy everything in "Proteus Library Files" to the LIBRARY folder of Proteus, for example:
     C:\Program Files (x86)\Labcenter Electronics\Proteus 8 Professional\LIBRARY
   (on some PCs: C:\ProgramData\Labcenter Electronics\Proteus 8 Professional\LIBRARY - use the folder that already holds
   Proteus's own .LIB files). TEPRPI3B.LIB is the Pi; TEPPMS5003.LIB, TEPAHT20.LIB, TEPRELAY.LIB, TEPLAPTOP.LIB and
   TEPMOBILE.LIB are the demo's parts.
3. Copy everything in "Proteus Model Files" - the DLLs AND the TEPPi folder - to the MODELS folder:
     C:\Program Files (x86)\Labcenter Electronics\Proteus 8 Professional\MODELS
   TEPPi holds Python 3.11 and the TEP Pi runtime; the Pi finds it next to TEPNET.DLL, in MODELS or next to your
   project. Replace an older TEPNET.DLL and TEPPi folder (these are the newest).
4. Delete TEPRPI3B.IDX (and the .IDX of a part library you replaced) from the LIBRARY folder if it is there.
5. Start Proteus. In Pick Devices (P) search "RASPBERRY".
Nothing else to install: Python is in TEPPi (no Python on the PC needed, none is changed).

RUN THE DEMO
Keep the .py file and the DLLs beside the project in "Proteus Simulation" (the TEPPi folder in MODELS).
  Pi-3-Model-B-WiFi-Air-Station.pdsprj - PI1 runs air_station.py on Wi-Fi (ETHERNET OUT): U1 = a PMS5003 particle
  sensor (TX to GPIO15 RXD, RX from GPIO14 TXD, VCC 5V; SET and RESET open - the sensor's own pull-ups), U2 = an AHT20
  (I2C 0x38, VIN 3V3), RLY1 = a 1-channel 5 V relay module (IN on GPIO17, active LOW, VCC 5V) whose contact switches
  the fan's supply - here R1 220R and the LED D1 in the fan's place (COM from 5V, NO to the load); PC1 = the Laptop
  WiFi Monitor and MOB1 = the Mobile WiFi Monitor on the same network. Every part is the Advance version: its pop-up
  window opens at Run with the live values and the controls to change them.
  Press Run: wlan0 joins "TEP-WiFi", the program starts http.server on port 8000, and each PMS5003 frame (every 2.3 s;
  the sensor's fan settles for 30 s, the first readings are low) brings a line: PM1.0, PM2.5 and PM10, the AHT20's
  temperature and humidity, the fan's state. On the laptop or the phone open http://192.168.1.51:8000/ (Browser,
  the address, Go): the page shows the readings and the links FAN ON, FAN OFF and AUTO. In AUTO (at the start) the fan
  goes on above 35 ug/m3 of PM2.5 and off below 25 - press SMOKE in the PMS5003's pop-up to see it switch; FAN ON /
  FAN OFF on the page switch it by hand (MANUAL) until you press AUTO. The program is pure Python - pyserial, smbus2,
  gpiozero and http.server, its own PMS5003 frame parser and AHT20 code.

YOUR OWN PROGRAMS
Write the program with any editor, put the .py next to your project and set the Pi's PROGRAM property to its name (or
a full path). Start from Python Code\blink.py (an LED on GPIO17). Python's standard library is there; other
pure-Python packages work when you copy them next to your program. Use BCM numbers (GPIO.setmode(GPIO.BCM),
gpiozero's LED(17)) or GPIO.setmode(GPIO.BOARD) with the header's pin numbers.
A program that never sleeps and never touches a pin for 3 real seconds is left running on its own (the simulation
goes on); input() waits for a line typed in the Pi Terminal.

THE 40-PIN HEADER (BCM numbers - the tags on the board)
   1 3V3        2 5V          3 GPIO2 SDA    4 5V          5 GPIO3 SCL    6 GND         7 GPIO4 (1-Wire)
   8 GPIO14 TXD 9 GND        10 GPIO15 RXD  11 GPIO17     12 GPIO18      13 GPIO27     14 GND
  15 GPIO22    16 GPIO23     17 3V3         18 GPIO24     19 GPIO10 MOSI 20 GND        21 GPIO9 MISO
  22 GPIO25    23 GPIO11 SCLK 24 GPIO8 CE0  25 GND        26 GPIO7 CE1   27 ID_SD      28 ID_SC
  29 GPIO5     30 GND        31 GPIO6       32 GPIO12     33 GPIO13      34 GND        35 GPIO19
  36 GPIO16    37 GPIO26     38 GPIO20      39 GND        40 GPIO21
3.3 V logic: GPIO2 / GPIO3 have the Pi's 1.8 k pull-ups to 3.3 V; RPi.GPIO's pull-ups / pull-downs are weak drives.
ID_SD / ID_SC (27, 28, GPIO0 / GPIO1) are kept for a HAT's ID EEPROM; leave them free, as on a real Pi.

PROPERTIES (double-click the Pi > Edit Properties)
  PROGRAM    the Python program (default blink.py; a name next to the project or a full path)
  AUTOOPEN   the Pi Terminal at Run: YES (default) or NO
  ETHERNET   the cable to the router at Run: OUT (default: the network on wlan0) or IN (eth0)
  WIFISSID   the Wi-Fi network wlan0 joins (default TEP-WiFi)
  WIFIPASS   its password (default 12345678)
  PYTHON     a python.exe of your own (empty: TEPPi's)
  RUNTIME    the TEP Pi runtime folder (empty: TEPPi's)

TROUBLESHOOTING
* "TEP Pi: the TEPPi folder ... was not found": copy the TEPPi folder from "Proteus Model Files" into MODELS (or next
  to the project).
* "python3: can't open file": the PROGRAM file is not next to the project - put it there or give a full path.
* ModuleNotFoundError for a package: only the libraries above are built in; copy a pure-Python package's folder next to
  your program.
* The program waits for Wi-Fi forever: check WIFISSID / WIFIPASS (the simulation log says "not found" or "wrong
  password"), or the cable is in (ETHERNET IN: then eth0 carries the network).
* The page does not open: the address is http://192.168.1.51:8000/ (the port the program serves), and the program must
  have printed "serving on".
* No PM readings: the PMS5003's TX goes to GPIO15 (RXD), 9600 baud; its SET must be open or HIGH (LOW = sleep).
* OSError: [Errno 121] Remote I/O error: no part answers at that address - check its VCC / GND and SDA / SCL.
* The relay does not switch: its VCC needs 5 V (the IN pin takes the Pi's 3.3 V); IN is active LOW - gpiozero's
  OutputDevice(17, active_high=False).
* A paused simulation shows the SIMULATION LOG: click the Schematic Capture tab.

BUG REPORTS AND FEATURE REQUESTS
Please post them in our forum with a screenshot, the program, the Pi Terminal's text and the simulation log:
  https://www.theengineeringprojects.com/forum/category/raspberry-pi-3-model-b-proteus-library

SUPPORT US
This library is free. If it saves you time, please support our work:
  https://www.theengineeringprojects.com/donate

WEBSITE
  https://www.theengineeringprojects.com/

LICENCES AND THIRD-PARTY NOTES
* The Raspberry Pi board model, the TEP Pi runtime, the Pi Terminal and the network (TEPNET.DLL, the compiled .pyc files
  in TEPPi\runtime with the stand-ins RPi, smbus2, smbus, spidev, serial, Adafruit_DHT, adafruit_dht, board), the
  symbols and artwork (TEPRPI3B.LIB), the part models (TEPPMS5003, TEPAHT20 and TEPRELAY .DLL / .LIB, the Laptop and
  Mobile WiFi Monitors' TEPLAPTOP.LIB / TEPMOBILE.LIB in TEPNET.DLL) and the demo program are made by The Engineering
  Projects. Our stand-ins follow the APIs of RPi.GPIO, smbus2, py-spidev, pyserial, Adafruit_DHT and
  adafruit-circuitpython-dht; none of their code is copied. The source code of the models is not included (nor the
  runtime's: it ships compiled for the included Python 3.11).
* TEPPi\python is the official embeddable Python 3.11.9 for Windows (32-bit) from python.org, unchanged, under the
  Python Software Foundation License (TEPPi\python\LICENSE.txt).
* TEPPi\runtime\gpiozero is gpiozero 2.0.1.post3 and TEPPi\runtime\colorzero is colorzero 2.0, unchanged, under the BSD
  3-Clause licence (their LICENSE files in the dist-info folders).
* Proteus is a product of Labcenter Electronics and is not included. Raspberry Pi is a trademark of Raspberry Pi Ltd.
  This library is not made or endorsed by Raspberry Pi Ltd or Labcenter.

MODEL SCOPE AND LIMITS
Modelled: the 26 GPIOs of the 40-pin header (inputs, outputs, RPi.GPIO's pull-ups / pull-downs, edges, software PWM),
the I2C, SPI, UART, 1-Wire and DHT buses as the Pi's drivers drive them, the supply pins, Wi-Fi (wlan0: the join, DHCP,
TCP and UDP to every TEP network part) and Ethernet (eth0, the cable), one interface at a time, the LEDs, a 0.5 s boot
before the program starts, the Pi's /proc and /sys files above, the Pi Terminal. Not modelled: Raspberry Pi OS (no
desktop, no shell commands, no apt, no os.system), Bluetooth, wlan0 and eth0 at the same time, Wi-Fi scanning from the
program, the four cores (one program, its threads take turns), the HDMI and A/V outputs, the camera and display
connectors, USB, the microSD card's files, hardware PWM (GPIO18 is software PWM here), a HAT's ID EEPROM, C programs and
C extensions, the real CPU's speed (each GPIO call takes about 3 us; pure Python code takes no simulation time),
real-time jitter. The model's own choices: the board's IP address (192.168.1.51 for PI1), the boot time, the router;
the simulation runs below real time.

VERSION
TEP Raspberry Pi 3 Model B library V1.0 (Oct 2026). Device RASPBERRY PI 3 MODEL B (TEPRPI3B.LIB / TEPNET.DLL with
TEPPi: Python 3.11.9 and the TEP Pi runtime 0.2). Demo program air_station.py V1.0, blink.py.