Using pyserial to interface with a power supply

Question

I am using a RS-232 to USB converter to connect my Agilent E3640A to my laptop. I am trying to return the manufacture's name using the command "*IDN" as stated in their manual. When i try to read the line, I get an empty string. I am also just having trouble putting the device in remote mode. Here is the link to their manual : https://all-guidesbox.com/model/agilent-technologies/e3640a.html

It seems that my power supply is not properly connected to my PC according to Keysight Connection Helper. It produces this error code:

! VI_ERROR_TMO: A timeout occurred
Visa ErrorCode: 0xBFFF0015 (-1073807339)
 ! Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index

My Code:

ser = serial.Serial()
ser.timeout = 20
ser.baudrate = 9600
ser.port = 'COM8'
print('Connected to ' + ser.name)
ser.open()
ser.reset_input_buffer()
ser.reset_output_buffer()
#ser.write('SYST:INT{RS232}'.encode('utf-8'))
ser.write(b'SYST:REM')
ser.flush()
ser.write('*IDN?'.encode('utf-8'))
ser.flush()
print(ser.readline())

Actual Output:

Connected to COM8
b''

Desired Output:

Connected to COM8
‘‘Agilent Technologies,E3640A,0,X.X-Y.Y-Z.Z’’

You need to terminate your command with a newline character (`\n`). — jasonharper, Oct 24 '19 at 18:22
So I just tried that: ser.write('*IDN?\n'.encode('utf-8')). ser.write(b'SYST:REM\n'). I still got the same output — Nycbros, Oct 24 '19 at 18:26
Double check that 9600 is the correct baud rate - it can be changed from the front panel. Sorry, no other ideas. — jasonharper, Oct 24 '19 at 18:49
can you use any program like hyperterm or minicom and first validate that you can send commands manually — gelonida, Oct 24 '19 at 18:49
I can confirm that 9600 is the correct baud rate. I am not familiar with hyperterm or minicom — Nycbros, Oct 24 '19 at 18:54
I just updated my question with a just discovered error message — Nycbros, Oct 24 '19 at 21:24
Until you can demonstrate that this works with a terminal program, it's really premature to be treating it as a programming problem. Time to learn about minicom or hyperterm or screen or whatever you like. — Chris Stratton, Oct 25 '19 at 04:05
Turns out I just had a bad cable. Do I just delete this post now? — Nycbros, Oct 28 '19 at 19:07

Using pyserial to interface with a power supply

0 Answers0