am2320.py 文件源码

def measure(self):
        buf = self.buf
        address = self.address
        # wake sensor
        try:
            self.i2c.writeto(address, b'')
        except OSError:
            pass
        # read 4 registers starting at offset 0x00
        self.i2c.writeto(address, b'\x03\x00\x04')
        # wait at least 1.5ms
        time.sleep_ms(2)
        # read data
        self.i2c.readfrom_mem_into(address, 0, buf)
        # debug print
        print(ustruct.unpack('BBBBBBBB', buf))
        crc = ustruct.unpack('<H', bytearray(buf[-2:]))[0]
        if (crc != self.crc16(buf[:-2])):
            raise Exception("checksum error")