BPI-Leaf-S3 OLED+DHT11 dislay temperature, humidity, and progress bar

Webduino & Arduino STEAM education BPI-Leaf-S3/BPI-PicoW-S3/Centi-S3
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We have designed a program to display the voltage of potentiometer and progress bar on the OLED screen in the previous page. What if we use SSD1306 OLED screen in combination with some sensors, like DHT11?

DHT11 is a basic and low cost digital temperature and humidity sensor. It uses capacitive humidity sensor and thermistor to measure the humidity in the surrounding area, and converts it to the digital signal. Then the signal will be transimitted to the microcontroller from the data pins, which can receive the humidity data through the single line communication protocol.

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How to connect

DHT11 Board
GND GND
DAT GPIO1
VCC 5V
SSD1306 OLED Board
GND GND
VCC 5V
SCL 16
SDA 15

Micropython

Micropython establishment of operating environment - Banana Pi Wiki (banana-pi.org)

Micropython framebuf documents

Micropython ssd1306.py on Github

Micropython DHT driver documents

Program code

from machine import Pin,I2C
from ssd1306 import SSD1306_I2C
import time
import dht

dht11 = dht.DHT11(Pin(1))

sda_pin=Pin(15,Pin.PULL_UP)
scl_pin=Pin(16,Pin.PULL_UP)

i2c = I2C(1,sda=sda_pin, scl=scl_pin, freq=800_000)
print(i2c.scan())
oled = SSD1306_I2C(128, 64, i2c, addr=0x3c)

#Init, white background
oled.fill(1)
oled.rect(0,22,128,10,0)
oled.rect(0,53,128,10,0)

while True:
    #Read DHT11
    dht11.measure() # Measure and read data once.
    temperature = dht11.temperature() # -20℃ ~ 60℃
    humidity = dht11.humidity() # 5%RH ~ 95%RH
    
    #Set temperature text, centered
    text_1 = str(temperature) + " C"
    start_x_1 = 64 - len(text_1)*4
    oled.fill_rect(0,14,128,8,1)
    oled.text(text_1,start_x_1,14,0)
    
    #Set temperature bar
    bar_1 = round ((temperature+20)/80 * 128)
    oled.fill_rect(bar_1,23,128-bar_1,8,0)
    oled.fill_rect(0,23,bar_1,8,1)
    
    #Set humidity text, centered
    text_2 = str(humidity) + " %RH"
    start_x_2 = 64 - len(text_2)*4
    oled.fill_rect(0,45,128,8,1)
    oled.text(text_2,start_x_2,45,0)
    
    #Set humidity bar
    humidity_bar = round (humidity/100 * 128)
    oled.fill_rect(humidity_bar,54,128-humidity_bar,8,0)
    oled.fill_rect(0,54,humidity_bar,8,1)
    
    #Show
    oled.show()
    
    print("Temperature={0}℃,Humidity={1}%RH".format(temperature,humidity))

Video demo:

Banana Pi BPI-Leaf-S3 wiki page: https://wiki.banana-pi.org/BPI-Leaf-S3

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