kopia lustrzana https://github.com/GuyCarver/MicroPython
92 wiersze
2.3 KiB
Python
92 wiersze
2.3 KiB
Python
#Driver for CJMCU-IR temperature sensor. Uses mlx90614 but adds serial interface to it.
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from machine import UART
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from utime import sleep_ms
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#Format of data output from the device:
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#length: 9
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# Byte0 Header Flags 0x66
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# Byte1 Header Flags 0x66
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# Byte2 data output mode (0x01 continuous output; 0x02 query output, the default for continuous output mode)
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# Byte3 Measured data length (counted by Byte)
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# Byte4 Temperature 1 Upper 8 bits
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# Byte5 Temperature 1 Lower 8 bits
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# Byte6 Temperature 2 Upper 8 bits
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# Byte7 Temperature 2 Lower 8 bits
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# Byte8 data parity (all data accumulation, take the low 8-bit)
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#
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#Celcius Temperature calculation method:
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#
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#Temperature = Data High 8 bits << 8 | Lower 8 bits of data, the result is the actual temperature multiplied by 100.
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#
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#Command instructions:
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#Lenght: 4
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#Byte0 Header Flags 0x66
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#Byte1 Header Flags 0x66
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#Byte2 Sets the command:
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# 0x01 Continuous output mode
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# 0x02 Query output mode
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# 0x11 Set the baud rate to 9600
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# 0x12 Set the baud rate to 57600
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# 0x13 Set the baud rate to 115200
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#Byte3 End of frame flag 0x56
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def c2f( aValue ):
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'''Celcius to Farenheit conversion.'''
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return (aValue * 9.0 / 5.0) + 32.0
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class cjmcu(object) :
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"""docstring for cjmcu"""
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_CONTINUOUS = const(1)
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_POLL = const(2)
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_RATEBASE = 0x11
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_BAUD9600 = const(0)
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_BAUD19200 = const(1)
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_BAUD38400 = const(2)
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def __init__(self, aLoc):
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print('super')
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super(cjmcu, self).__init__()
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print('creating uart')
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sleep_ms(1000)
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self._uart = UART(aLoc, 19200)
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print('init')
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sleep_ms(1000)
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self._mode = _POLL
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self._output = bytearray(4)
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self._output[0] = 0x66
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self._output[1] = 0x66
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self._output[2] = self._mode
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self._output[3] = 0x56
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self._input = bytearray(9)
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self.update()
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def write( self ) :
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print('write', self._output)
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self._uart.write(self._output)
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def read( self ) :
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print('read', len(self.input))
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self._uart.readinto(self._input)
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def update( self ) :
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self.write()
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self.read()
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def setbaud( self, aBaud ) :
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self._output[2] = _BAUDBASE + aBaud
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self.update()
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self._output[2] = self._mode
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self._uart.deinit()
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self._uart.init(9600 << aBaud)
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def temps( self ) :
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v1 = (self._input[4] << 8) | self._input[5]
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v2 = (self._input[6] << 8) | self._input[7]
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return (v1 / 100.0, v2 / 100.0)
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