Sending G-code commands to Hyrel System 30M using python I am using python 3.6 with pySerial library to connect to the Hyrel System 30M 3D Printer. I am able to read the data from the device but unable to write any commands to it

Here is the code:



    ser = serial.Serial()
    ser.port = 'COM4'
    ser.baudrate = 38400
    out = ser.readline()
    ser.write(b'M106 T14 S30\n') %This is the command to turn on the fan at 30% power


Can somebody suggest me how to write commands to printer through python
If the one in your question is your complete code, a possibility is that your computer is just buffering the output for the serial port, withholding it in memory.  Try to add

ser.flush()


after your last line.  This command will... well... flush anything into the buffer through the actual connection.