64 lines
2.1 KiB
Python
64 lines
2.1 KiB
Python
#!/usr/bin/env python3
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#############################################################################
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# Filename : ADC.py
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# Description : ADC and DAC
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# Author : freenove
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# modification: 2018/09/15
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########################################################################
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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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self.address = 0x48 #default address of PCF8591
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self.bus=smbus.SMBus(1)
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self.cmd=0x40 #command
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def analogRead(self,chn):#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.cmd+chn)
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value=sorted(value)
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return value[4]
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def analogWrite(self,value):#write DAC value
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self.bus.write_byte_data(address,cmd,value)
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def loop(self):
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while True:
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self.value = self.analogRead(2) #read the ADC value of channel 0,1,2,3
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#analogWrite(value) #write the DAC value
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self.voltage = self.value / 256.0 * 3.3 #calculate the voltage value
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print ('ADC Value : %d, Voltage : %.2f'%(self.value,self.voltage))
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time.sleep(0.01)
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def recvADC(self,channel):
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while(1):
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self.value = self.analogRead(channel) #read the ADC value of channel 0,1,2,
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self.value1 = self.analogRead(channel)
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if self.value==self.value1:
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break;
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self.voltage = self.value / 256.0 * 3.3 #calculate the voltage value
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self.voltage = round(self.voltage,2)
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return self.voltage
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def destroy():
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self.bus.close()
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def loop():
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while True:
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adc=Adc()
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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)
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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() |