PlantSeminar_PythonServer/InputReader.py at master · FrancescoDAlterio/PlantSeminar_PythonServer · GitHub

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import time
import os
import RPi.GPIO as GPIO


class InputReader():


    def read_analogic_sensor(self,sensor_pin):
        GPIO.setmode (GPIO.BCM)

        # change these as desired - they're the pins connected from the
        # SPI port on the ADC to the Cobbler
        SPICLK = 18
        SPIMISO = 23
        SPIMOSI = 24
        SPICS = 25

        # set up the SPI interface pins
        GPIO.setup (SPIMOSI, GPIO.OUT)
        GPIO.setup (SPIMISO, GPIO.IN)
        GPIO.setup (SPICLK, GPIO.OUT)
        GPIO.setup (SPICS, GPIO.OUT)

        try:
            sensor_pin_toInt = int (sensor_pin)
        except:
            return -1

        return self.__readadc(sensor_pin_toInt, SPICLK, SPIMOSI, SPIMISO, SPICS)


    def read_digital_sensor(self,sensor_pin):
        try:
            sensor_pin_toInt = int (sensor_pin)
        except:
            return -1

        GPIO.setmode (GPIO.BCM)
        GPIO.setup (sensor_pin_toInt, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)

        return GPIO.input (sensor_pin_toInt)


    # read SPI data from MCP3008 chip, 8 possible adc's (0 thru 7)
    def __readadc(self,adcnum, clockpin, mosipin, misopin, cspin):
        if ((adcnum > 7) or (adcnum < 0)):
            return -1
        GPIO.output (cspin, True)

        GPIO.output (clockpin, False)  # start clock low
        GPIO.output (cspin, False)  # bring CS low

        commandout = adcnum
        commandout |= 0x18  # start bit + single-ended bit
        commandout <<= 3  # we only need to send 5 bits here
        for i in range (5):
            if (commandout & 0x80):
                GPIO.output (mosipin, True)
            else:
                GPIO.output (mosipin, False)
            commandout <<= 1
            GPIO.output (clockpin, True)
            GPIO.output (clockpin, False)

        adcout = 0
        # read in one empty bit, one null bit and 10 ADC bits
        for i in range (12):
            GPIO.output (clockpin, True)
            GPIO.output (clockpin, False)
            adcout <<= 1
            if (GPIO.input (misopin)):
                adcout |= 0x1

        GPIO.output (cspin, True)

        adcout >>= 1  # first bit is 'null' so drop it
        return adcout