108 lines
4.5 KiB
Python
108 lines
4.5 KiB
Python
import smbus
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import time
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class Adc:
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def __init__(self):
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# Get I2C bus
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self.bus = smbus.SMBus(1)
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# I2C address of the device
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self.ADDRESS = 0x48
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# PCF8591 Command
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self.PCF8591_CMD =0x40 #Command
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# ADS7830 Command Set
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self.ADS7830_CMD_SD_SINGLE = 0x84 # Single-Ended Inputs
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self.ADS7830_CMD_SNGL_CHANNEL_0 = 0x00 # +IN = CH0, -IN = GND
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self.ADS7830_CMD_SNGL_CHANNEL_1 = 0x40 # +IN = CH1, -IN = GND
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self.ADS7830_CMD_SNGL_CHANNEL_2 = 0x10 # +IN = CH2, -IN = GND
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self.ADS7830_CMD_SNGL_CHANNEL_3 = 0x50 # +IN = CH3, -IN = GND
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self.ADS7830_CMD_SNGL_CHANNEL_4 = 0x20 # +IN = CH4, -IN = GND
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self.ADS7830_CMD_SNGL_CHANNEL_5 = 0x60 # +IN = CH5, -IN = GND
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self.ADS7830_CMD_SNGL_CHANNEL_6 = 0x30 # +IN = CH6, -IN = GND
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self.ADS7830_CMD_SNGL_CHANNEL_7 = 0x70 # +IN = CH7, -IN = GND
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self.ADS7830_CMD_PD_POWER_DOWN = 0x00 # Power Down Between A/D Converter Conversions
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self.ADS7830_CMD_PD_REF_OFF = 0x04 # Internal Reference OFF and A/D Converter ON
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self.ADS7830_CMD_PD_REF_ON = 0x08 # Internal Reference ON and A/D Converter OFF
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self.ADS7830_CMD_PD_REF_ON_AD_ON = 0x0C # Internal Reference ON and A/D Converter ON
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for i in range(3):
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aa=self.bus.read_byte_data(self.ADDRESS,0xf4)
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if aa < 150:
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self.Index="PCF8591"
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else:
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self.Index="ADS7830"
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def analogReadPCF8591(self,chn):#PCF8591 read ADC value,chn:0,1,2,3
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value=[0,0,0,0,0,0,0,0,0]
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for i in range(9):
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value[i] = self.bus.read_byte_data(self.ADDRESS,self.PCF8591_CMD+chn)
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value=sorted(value)
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return value[4]
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def analogWritePCF8591(self,value):#PCF8591 write DAC value
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self.bus.write_byte_data(self.ADDRESS,cmd,value)
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def recvPCF8591(self,channel):#PCF8591 write DAC value
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while(1):
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value1 = self.analogReadPCF8591(channel) #read the ADC value of channel 0,1,2,
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value2 = self.analogReadPCF8591(channel)
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if value1==value2:
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break;
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voltage = value1 / 256.0 * 3.3 #calculate the voltage value
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voltage = round(voltage,2)
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return voltage
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def recvADS7830(self,channel):
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"""Select the Command data from the given provided value above"""
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if channel == 0:
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COMMAND_SET = (self.ADS7830_CMD_SD_SINGLE | self.ADS7830_CMD_SNGL_CHANNEL_0)
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elif channel == 1:
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COMMAND_SET = (self.ADS7830_CMD_SD_SINGLE | self.ADS7830_CMD_SNGL_CHANNEL_1)
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elif channel == 2:
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COMMAND_SET = (self.ADS7830_CMD_SD_SINGLE | self.ADS7830_CMD_SNGL_CHANNEL_2)
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elif channel == 3:
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COMMAND_SET = (self.ADS7830_CMD_SD_SINGLE | self.ADS7830_CMD_SNGL_CHANNEL_3)
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elif channel == 4:
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COMMAND_SET = (self.ADS7830_CMD_SD_SINGLE | self.ADS7830_CMD_SNGL_CHANNEL_4)
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elif channel == 5:
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COMMAND_SET = (self.ADS7830_CMD_SD_SINGLE | self.ADS7830_CMD_SNGL_CHANNEL_5)
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elif channel == 6:
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COMMAND_SET = (self.ADS7830_CMD_SD_SINGLE | self.ADS7830_CMD_SNGL_CHANNEL_6)
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elif channel == 7:
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COMMAND_SET = (self.ADS7830_CMD_SD_SINGLE | self.ADS7830_CMD_SNGL_CHANNEL_7)
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self.bus.write_byte(self.ADDRESS, COMMAND_SET)
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while(1):
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value1 = self.bus.read_byte(self.ADDRESS)
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value2 = self.bus.read_byte(self.ADDRESS)
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if value1==value2:
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break;
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voltage = value1 / 256.0 * 3.3 #calculate the voltage value
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voltage = round(voltage,2)
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return voltage
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def recvADC(self,channel):
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if self.Index=="PCF8591":
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data=self.recvPCF8591(channel)
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elif self.Index=="ADS7830":
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data=self.recvADS7830(channel)
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return data
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def i2cClose(self):
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self.bus.close()
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def loop():
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adc=Adc()
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while True:
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Left_IDR=adc.recvADC(0)
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print (Left_IDR)
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Right_IDR=adc.recvADC(1)
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print (Right_IDR)
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Power=adc.recvADC(2)*3
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print (Power)
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time.sleep(1)
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print ('----')
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def destroy():
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pass
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# Main program logic follows:
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if __name__ == '__main__':
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print ('Program is starting ... ')
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try:
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loop()
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except KeyboardInterrupt: # When 'Ctrl+C' is pressed, the child program destroy() will be executed.
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destroy()
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