89 lines
1.8 KiB
Python
89 lines
1.8 KiB
Python
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#import sys
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import wiringpi
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from wiringpi import GPIO
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PIN = 6
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def oneWireReset(pin):
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wiringpi.pinMode(pin, GPIO.OUTPUT)
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wiringpi.digitalWrite(pin, GPIO.HIGH)
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wiringpi.digitalWrite(pin, GPIO.LOW)
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wiringpi.delayMicroseconds(500)
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wiringpi.digitalWrite(pin, GPIO.HIGH)
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wiringpi.delayMicroseconds(60)
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wiringpi.pinMode(pin, GPIO.INPUT)
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if not wiringpi.digitalRead(pin):
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ack = 1
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else:
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ack = 0
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wiringpi.delayMicroseconds(500)
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return ack
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def writeBit(pin, bit):
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wiringpi.pinMode(pin, GPIO.OUTPUT)
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wiringpi.digitalWrite(pin, GPIO.LOW)
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wiringpi.delayMicroseconds(2)
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wiringpi.digitalWrite(pin, bit)
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wiringpi.delayMicroseconds(80)
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wiringpi.digitalWrite(pin, GPIO.HIGH)
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wiringpi.delayMicroseconds(1)
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def oneWireSendComm(pin, byte):
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i = 0
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while i < 8:
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sta = byte & 0x01
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writeBit(pin, sta)
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byte >>= 1
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i += 1
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def readBit(pin):
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wiringpi.pinMode(pin, GPIO.OUTPUT)
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wiringpi.digitalWrite(pin, GPIO.HIGH)
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wiringpi.digitalWrite(pin, GPIO.LOW)
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wiringpi.delayMicroseconds(2)
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wiringpi.digitalWrite(pin, GPIO.HIGH)
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wiringpi.pinMode(pin, GPIO.INPUT)
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wiringpi.delayMicroseconds(2)
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tmp = wiringpi.digitalRead(pin)
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wiringpi.delayMicroseconds(40)
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return tmp
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def oneWireReceive(pin):
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i = 0
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k = 0
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while i < 8:
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j = readBit(pin)
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k = (j << 7) | (k >> 1)
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i += 1
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k = k & 0x00FF
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return k
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def tempchange(lsb, msb):
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if (msb >= 0xF0):
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msb = 255 - msb
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lsb = 256 - lsb
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tem = -(msb*16*16 + lsb)
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else:
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tem = (msb*16*16 + lsb)
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temp = tem*0.0625
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print("Current Temp: %.2f"%(temp))
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def main():
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wiringpi.wiringPiSetup()
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if oneWireReset(PIN):
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oneWireSendComm(PIN, 0xcc)
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oneWireSendComm(PIN, 0x44)
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if oneWireReset(PIN):
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oneWireSendComm(PIN, 0xcc)
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oneWireSendComm(PIN, 0xbe)
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lsb = oneWireReceive(PIN)
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msb = oneWireReceive(PIN)
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tempchange(lsb, msb)
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if __name__ == '__main__':
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main()
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