.. note:: Hello, welcome to the SunFounder Raspberry Pi & Arduino & ESP32 Enthusiasts Community on Facebook! Dive deeper into Raspberry Pi, Arduino, and ESP32 with fellow enthusiasts. **Why Join?** - **Expert Support**: Solve post-sale issues and technical challenges with help from our community and team. - **Learn & Share**: Exchange tips and tutorials to enhance your skills. - **Exclusive Previews**: Get early access to new product announcements and sneak peeks. - **Special Discounts**: Enjoy exclusive discounts on our newest products. - **Festive Promotions and Giveaways**: Take part in giveaways and holiday promotions. 👉 Ready to explore and create with us? Click [|link_sf_facebook|] and join today! .. _py_plant_monitor: 6.8 Plant Monitor =============================== Welcome to the Plant Monitor project! In this project, we will be using an ESP32 board to create a system that helps us take care of our plants. With this system, we can monitor the temperature, humidity, soil moisture, and light levels of our plants, and ensure that they are getting the care and attention they need to thrive. **Required Components** In this project, we need the following components. It's definitely convenient to buy a whole kit, here's the link: .. list-table:: :widths: 20 20 20 :header-rows: 1 * - Name - ITEMS IN THIS KIT - LINK * - ESP32 Starter Kit - 320+ - |link_esp32_starter_kit| You can also buy them separately from the links below. .. list-table:: :widths: 30 20 :header-rows: 1 * - COMPONENT INTRODUCTION - PURCHASE LINK * - :ref:`cpn_esp32_wroom_32e` - |link_esp32_wroom_32e_buy| * - :ref:`cpn_esp32_camera_extension` - |link_esp32_extension_board| * - :ref:`cpn_breadboard` - |link_breadboard_buy| * - :ref:`cpn_wires` - |link_wires_buy| * - :ref:`cpn_resistor` - |link_resistor_buy| * - :ref:`cpn_dht11` - |link_dht11_buy| * - :ref:`cpn_lcd` - |link_i2clcd1602_buy| * - :ref:`cpn_pump` - \- * - :ref:`cpn_l293d` - \- * - :ref:`cpn_button` - |link_button_buy| * - :ref:`cpn_photoresistor` - |link_photoresistor_buy| * - :ref:`cpn_soil_moisture` - |link_soil_moisture_buy| **Schematic** .. image:: ../../img/circuit/circuit_6.8_plant_monitor_l293d.png The system uses a DHT11 sensor to measure the temperature and humidity levels of the surrounding environment. Meanwhile, a soil moisture module is used to measure the moisture level of the soil and a photoresistor is used to measure the light level. The readings from these sensors are displayed on an LCD screen, and a water pump can be controlled using a button to water the plant when needed. IO32 has an internal pull-down resistor of 1K, and by default, it is at a low logic level. When the button is pressed, it establishes a connection to VCC (high voltage), resulting in a high logic level on IO32. **Wiring** .. note:: It is recommended here to insert the battery and then slide the switch on the expansion board to the ON position to activate the battery supply. .. image:: ../../img/wiring/6.8_plant_monitor_l293d_bb.png :width: 800 **Code** .. note:: * Open the ``6.8_plant_monitor.py`` file located in the ``esp32-starter-kit-main\micropython\codes`` path, or copy and paste the code into Thonny. Then, click "Run Current Script" or press F5 to execute it. * Make sure to select the "MicroPython (ESP32).COMxx" interpreter in the bottom right corner. .. code-block:: python from machine import ADC, Pin import time import dht from lcd1602 import LCD # DHT11 dht11 = dht.DHT11(Pin(13)) # Soil moisture moisture_pin = ADC(Pin(14)) moisture_pin.atten(ADC.ATTN_11DB) # Photoresistor photoresistor = ADC(Pin(35)) photoresistor.atten(ADC.ATTN_11DB) # Button and pump button = Pin(32, Pin.IN) motor1A = Pin(27, Pin.OUT) motor2A = Pin(26, Pin.OUT) # I2C LCD1602 setup lcd = LCD() # Rotate the pump def rotate(): motor1A.value(1) motor2A.value(0) # Stop the pump def stop(): motor1A.value(0) motor2A.value(0) button_state = False # Define the button callback function to toggle the button state def button_callback(pin): global button_state button_state = not button_state # Attach the button callback function to the rising edge of the button pin button.irq(trigger=Pin.IRQ_RISING, handler=button_callback) page = 0 temp = 0 humi = 0 try: while True: # If the button is pressed and button state is True if button_state: print("rotate") rotate() # If the button is pressed again and button state is False if not button_state: print("stop") stop() time.sleep(2) # Clear the LCD display lcd.clear() # Toggle the value of the page variable between 0 and 1 page=(page+1)%2 # When page is 1, display temperature and humidity on the LCD1602 if page is 1: try: # Measure temperature and humidity dht11.measure() # Get temperature and humidity values temp = dht11.temperature() humi = dht11.humidity() except Exception as e: print("Error: ", e) # Display temperature and humidity lcd.write(0, 0, "Temp: {}\xDFC".format(temp)) lcd.write(0, 1, "Humi: {}%".format(humi)) # If page is 0, display the soil moisture and light else: light = photoresistor.read() moisture = moisture_pin.read() # Clear the LCD display lcd.clear() # Display the value of soil moisture and light lcd.write(0, 0, f"Moisture: {moisture}") lcd.write(0, 1, f"Light: {light}") except KeyboardInterrupt: # Stop the motor when KeyboardInterrupt is caught stop() * When the code is running, the I2C LCD1602 alternately displays temperature and humidity, as well as soil moisture and light intensity analog values, with a 2-second interval. * Press the button to start the water pump, and press it again to stop the water pump. .. note:: If the code and wiring are correct, but the LCD still fails to display any content, you can adjust the potentiometer on the back to increase the contrast.