通过python中的rs485进行通信

Question

I am new in python. I am trying to catch data from temperature sensor via RS485 in python

Here my code:

ser = serial.Serial(
port='COM3',
baudrate=19200,
parity=serial.PARITY_NONE,
stopbits=serial.STOPBITS_ONE,
bytesize=serial.EIGHTBITS)

print ser.write('{02RDD}\r')

Response: >> 8

The response is always string length (ex ser.write("abcd"), response is "4") no matter what I send.

Please help me how to solve this problem, Thanks

Answer 1

If you want to read from the serial port use ser.read() or ser.readline() .

The ser.write() , which you have used, only returns the number of bytes sent, which should correspond to the length of the string. So it seems to work correctly.

You should maybe go though the examples that are given in the pyserial documentation to make youself more familiar with the library.