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Products => Test Equipment => Topic started by: simba15 on October 18, 2021, 03:49:49 pm

Title: Keithley 2231A-30-3 Communication
Post by: simba15 on October 18, 2021, 03:49:49 pm
Hi there,

I am working with a large number of the Keithley 2231A-30-3.

I would like to communicate with it VIA PC but Tek, states you must use the Keithley USB adapter ($$$)

I have found the pin-out of the propriety connector (2=rx,3=tX).

Has any one been able to get this power supply to communicate to their pc? ( may only respond to read only commands)

Thanks.
Title: Re: Keithley 2231A-30-3 Communication
Post by: simba15 on January 11, 2022, 02:30:35 pm
So I connected a FTDI TTL adapter tx/rx and tried with EEZ studio to get a response for a *IDN? command.

I cant get a response in the software but i can see that both Tx/Rx lights illuminate. (there is a response of some kind.)

Any ideas where the issue could be?

I will try with "Test controller" software.
Title: Re: Keithley 2231A-30-3 Communication
Post by: alm on January 11, 2022, 02:35:30 pm
Did you try different baud rates / flow control / parity / stop bit configurations? If it outputs anything on power on, you could capture that with a scope or logic analyzer and check the repetition rate and count the number of bits.
Title: Re: Keithley 2231A-30-3 Communication
Post by: simba15 on January 11, 2022, 02:48:50 pm
Quote from: alm on January 11, 2022, 02:35:30 pm
Did you try different baud rates / flow control / parity / stop bit configurations? If it outputs anything on power on, you could capture that with a scope or logic analyzer and check the repetition rate and count the number of bits.

So the Manual Lists the Baud rate and flow settings 9600,8,N,1 ( this is what the program is set for)

If i use a incorrect baud rate 57600 or other, the RX light dose not illuminate.

I will try and scope the RX Line.
Title: Re: Keithley 2231A-30-3 Communication
Post by: BennoG on February 19, 2024, 06:24:58 am
was you been able to communicate with the device ?
It uses 3.3V level RS232 signals at 9600 baud.

I found it to be very slow for the measurements of the output Voltage and Current (300+ ms per query)
Have you come around this problem ?

Benno
Title: Re: Keithley 2231A-30-3 Communication
Post by: simba15 on April 23, 2024, 03:24:17 pm
interesting!

I probably fried it with standard RS232 levels as it stopped responding at some point. ( duh... it says (TTL) lol)

I have 10 or so of them so I may try again with 3.3v levels.

Thanks.
Title: Re: Keithley 2231A-30-3 Communication
Post by: BennoG on April 23, 2024, 03:48:35 pm
Be also aware that the RS232 output uses the same ground level as CH3 output.
So I put also a isolator in the USB-RS232 converter (there is 5V on the 9 pin sub-D to supply the psu part of the logic)

P.S. I figured a way around the slow communication, see my other post in  on the 2231A, including C# source code and a nice HMI you can use to click on.

Benno