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pythonserial-portpyserialuart

PySerial can read but not write


I'm trying to use PySerial to connect to an FTDI FT232R chip. I have verified communication with my RealTerm and, using RealTerm, can both send and receive data. However, my implementation in Python can only receive data.

I am trying to write using this line:

for i in range(0,100):
    print "Loop "+str(i)
    print "Sending byte"
    ser.flush()
    print ser.write("B".encode('ascii'))
    time.sleep(1)

Solution

  • Comunication depends on the configuration of the chip, the connecting cable and the parameters of PySerial.

    This looks like a problem of the connections of the cable or the communications protocol (handshaking).

    This last one is the simplest to check. It can be Xon/Xoff, hardware, or none, but it has to be the same at both sides.

    If the handshaking is by hardware it depends on other lines of the cable besides trx and rcv.