라즈베리파이4 GPIO 제어

Digital Input/Ouput

import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM)

def setup_digital(pin):
    GPIO.setup(pin, GPIO.OUT)

def digital_on(pin):
    print("digital_on", pin)
    GPIO.output(pin, 1)

def digital_off(pin):
    print("digital_off", pin)
    GPIO.output(pin, 0)

def get_digital_staus(pin):
    return GPIO.input(pin)

Analog Input

import spidev
import time

sample = 10
sampleValue = []

spi = spidev.SpiDev()
spi.open(0,0)
spi.max_speed_hz = 1000000

def adc_read(channel):
    r = spi.xfer2([1, (0x08+channel)<<4, 0])
    adc_out = ((r[1]&0x03)<<8) + r[2]
    return adc_out

Custom Sensor

DHT22

• pip3 install adafruit-circuitpython-dht

• sudo apt-get install libgpiod2

import time
import board
import adafruit_dht

dhtDevice = adafruit_dht.DHT22(board.D22)

def read_temp():
    return dhtDevice.temperature

def read_huminity():
    return dhtDevice.humidity

PH Sensor

def phSensor_read(channel):
    for i in range(sample):
        adc = adc_read(channel)
        sampleValue.append(adc)
        time.sleep(0.10)

    sampleValue.sort()

    avg = 0
    for i in range(2, 8):
        avg += sampleValue[i]
    
    phValue = float(avg * 5 / 1024 /6)
    phValue = float(3.5 * phValue)

    sampleValue.clear()
    return phValue

Turbidity Sensor

def turbidity_read(channel):
    sampleValue = []
    for i in range(sample):
        adc = adc_read(channel)
        voltage = adc * (5.0 / 1024.0)
        sampleValue.append(voltage)

    sampleValue.sort()
    avg = 0
    for i in range(2, 8):
        avg += sampleValue[i]
    voltage = avg / 6
    return voltage