Circuit Documentation
Summary
This circuit integrates a Raspberry Pi Pico W microcontroller with an RGB LED and a resistor. The microcontroller is programmed to interact with various peripherals, including sensors and an LCD display, and to connect to a Wi-Fi network for MQTT communication. The RGB LED is controlled by the microcontroller to display different colors, and a resistor is used to limit the current to the LED.
Component List
Raspberry Pi Pico W
- Description: A microcontroller board based on the RP2040 microcontroller, featuring Wi-Fi connectivity.
- Pins: VBUS, VSYS, GP16, GP17, GND, GP18, GP19, GP20, GP21, GP22, RUN, GP26, GP27, GP28, ADC_VREF, 3V3 OUT, 3V3_EN, GP0, GP1, GP2, GP3, GP4, GP5, GP6, GP7, GP15, GP14, GP13, GP12, GP11, GP10, GP9, GP8.
RGB LED (Wokwi compatible)
- Description: A four-pin RGB LED capable of displaying a range of colors by mixing red, green, and blue light.
- Pins: R, COM, G, B.
Resistor
- Description: A passive two-terminal electrical component that implements electrical resistance as a circuit element.
- Resistance: 330 Ohms.
Wiring Details
Raspberry Pi Pico W
- GP17: Connected to the blue pin (B) of the RGB LED.
- GP18: Connected to the green pin (G) of the RGB LED.
- GP19: Connected to the red pin (R) of the RGB LED.
- 3V3 OUT: Connected to pin1 of the Resistor.
RGB LED (Wokwi compatible)
- R (Red): Connected to GP19 of the Raspberry Pi Pico W.
- G (Green): Connected to GP18 of the Raspberry Pi Pico W.
- B (Blue): Connected to GP17 of the Raspberry Pi Pico W.
- COM (Common Anode): Connected to pin2 of the Resistor.
Resistor
- pin1: Connected to 3V3 OUT of the Raspberry Pi Pico W.
- pin2: Connected to the COM pin of the RGB LED.
Documented Code
import machine
import network
import time
import dht
from machine import Pin
from machine import I2C
from lcd_api import LcdApi
from i2c_lcd import I2cLcd
from time import sleep
import utime
from umqtt.simple import MQTTClient
SSID = "project"
PASSWORD = "12345678"
MQTT_BROKER = "test.mosquitto.org"
MQTT_TOPIC = "JN_17102024"
# Set up the DHT11 sensor
dht_pin = machine.Pin(4) # Change this to the GPIO pin you connected the DHT11 data pin to
dht_sensor = dht.DHT11(dht_pin)
degree_celsius_symbol = chr(223)
ldr_pin = machine.ADC(26) # LDR sensor (light detection)
microwave_sensor = machine.Pin(16, machine.Pin.IN)
light = machine.Pin(6, machine.Pin.OUT) # LED 1
fan = machine.Pin(7, machine.Pin.OUT) # LED 2
button1 = machine.Pin(8, machine.Pin.IN)
button2 = machine.Pin(9, machine.Pin.IN)
light.value(1)
fan.value(1)
current_mode = None
I2C_ADDR = 0x27
totalRows = 2
totalColumns = 16
sensor = dht.DHT11(Pin(6))
i2c = I2C(1, sda=machine.Pin(2), scl=machine.Pin(3), freq=400000)
lcd = I2cLcd(i2c, I2C_ADDR, totalRows, totalColumns)
lcd.clear()
lcd.putstr(" WELCOME ")
lcd.move_to(0,1)
lcd.putstr("________________")
time.sleep(1)
lcd.clear()
lcd.putstr("SELECT MODE")
time.sleep(1)
def connect_wifi():
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
if not wlan.isconnected():
print('Connecting to Wi-Fi...')
lcd.clear()
lcd.putstr("CONNECTING")
lcd.move_to(0,1)
lcd.putstr("WIFI....")
time.sleep(2)
wlan.connect(SSID, PASSWORD)
while not wlan.isconnected():
time.sleep(1)
print('Connected to Wi-Fi:', wlan.ifconfig())
lcd.clear()
lcd.putstr("WIFI")
lcd.move_to(0,1)
lcd.putstr("CONNECTED")
time.sleep(2)
# Function to handle MQTT messages
def mqtt_callback(topic, msg):
print((topic, msg))
# Check message and control LED
if msg == b'a':
light.value(0)
elif msg == b'b':
light.value(1)
elif msg == b'c':
fan.value(0)
elif msg == b'd':
fan.value(1)
# Connect to the MQTT broker and subscribe to the topic
def connect_mqtt():
client = MQTTClient('raspberry_pi_pico', MQTT_BROKER)
lcd.clear()
lcd.putstr("MQTT")
lcd.move_to(0,1)
lcd.putstr("CONNECTING..")
time.sleep(2)
client.set_callback(mqtt_callback)
client.connect()
client.subscribe(MQTT_TOPIC)
print(f"Subscribed to topic {MQTT_TOPIC}")
lcd.clear()
lcd.putstr("MQTT")
lcd.move_to(0,1)
lcd.putstr("CONNECTED")
time.sleep(2)
while True:
client.check_msg() # Continuously check for incoming messages
time.sleep(1)
if button2.value() == 0:
break
def sensor_control():
while True:
movement_detected = microwave_sensor.value()
dht_sensor.measure()
temperature_c = dht_sensor.temperature()
temperature_string = f'{temperature_c}{degree_celsius_symbol}C'
humidity = dht_sensor.humidity()
print(movement_detected)
if movement_detected == 1:
lcd.clear()
lcd.putstr("MOVEMENT")
lcd.putstr(" DET")
time.sleep(2)
for i in range(60, 0, -1): # Reverse loop from 100 to 1
if i>=40:
fan.value(0)
lcd.clear()
lcd.putstr("Time:")
lcd.putstr(str(i)) # Countdown
lcd.putstr(" SECS")
lcd.move_to(0,1)
lcd.putstr("T:")
lcd.putstr(str(temperature_string))
lcd.putstr(" H:")
lcd.putstr(str(humidity))
lcd.putstr("%")
time.sleep(1)
light_value = ldr_pin.read_u16()
if light_value <= 10000:
light.value(0)
if light_value >= 20000:
light.value(1)
if temperature_c >= 35:
fan.value(0)
if temperature_c <= 34:
fan.value(1)
if button1.value() == 0:
break
if movement_detected == 0:
lcd.clear()
lcd.putstr("NO MOVEMENT")
light.value(1)
fan.value(1)
if button1.value() == 0:
break
# Main function
while True:
if button1.value() == 0:
current_mode = "app_mode"
if current_mode == "app_mode":
lcd.clear()
lcd.putstr("APP MODE")
lcd.move_to(0,1)
lcd.putstr("IOT CONTROL")
time.sleep(1)
connect_wifi()
connect_mqtt()
if button2.value() == 0:
current_mode = "automatic_mode"
if current_mode == "automatic_mode":
lcd.clear()
lcd.putstr("AUTOMATIC MODE")
lcd.move_to(0,1)
lcd.putstr("SENSOR CONTROL")
time.sleep(1)
sensor_control()
The code provided is for the Raspberry Pi Pico W microcontroller. It includes functionality for connecting to a Wi-Fi network, handling MQTT messages, controlling an RGB LED, and reading from sensors. The code also includes a user interface with an LCD display to show status messages and sensor readings.