G5100 Programmable Function Generator - Page 1
Forum section: electronics / testgear

author: richsf
author_rank: Contributor
timestamp: January 22, 2024, 06:26:14 pm
content: Hi, I have a G5100 Function Generator with the Circuit Specialists brand, however quite a few companies put there name on this equipment possibly initially manufactured by a company Seintek, S. Korea, which does not sell direct to end users. I got it in about 2003 new.There is a RS-232 serial interface, and other than how to set the baud rate from the front panel, I have no other information. The RS-232 port does echo characters, but doesn't provide any power up message or respond to anything I type at it.Before anyone suggests it, I have the original user manual, I have covered all the bases trying to get support with no responses. The product is obsolete of course.Does anyone have any information on how to use the RS-232 interface ? There was a program that shipped with the unit, but I'm sure I lost it.I think only someone that has this equipment and either has the original program or uses the RS-232 on it can help. The dealers have nothing.Thanks

author: thm_w
author_rank: Super Contributor
timestamp: January 22, 2024, 10:51:25 pm
content: The manual you are talking about seems to have all of the commands listed:https://www.peaktech.de/media/9f/b1/68/1617260670/PeakTech_1015_GPIB_englisch.pdfI would start first by sending: "*IDN?" + CR LF see if it you get a response, then go from there.

author: richsf
author_rank: Contributor
timestamp: January 23, 2024, 12:25:09 pm
content: First, thank you very much. That manual covers the commands, the manual that I got with the unit which I purchased new in about 2003/4 came with a paper manual that did not cover the commands, and the pdfs I had found on-line matched my limited manual, however this G5100 does have a DB9, and a setup menu on the front panel that sets baud rate.My Firmware version is 7.01 which shows in the panel display, and shows serial #G000721.I am using minicom, and I have confirmed that the G5100 is echoing characters at 9600 baud, and if I change the baud rate it does not echo, so it is not echoing in any kind of hardware loop back, the characters are being received and the firmware is echoing them back. I also observe that if I turn on hardware flow control in minicom the function generator does not echo, not sure what that means, probably that they didn't implement it. When hardware flow control is off it does echo. The only thing the front panel allows you to do is to set the baud rate, 9600 is the top rate.*IDN? does not respond with the Model information that the manual describes. No commands respond that I have tried.So, it is a mystery. I'll pop it open and see if there is anything to see there. Maybe the firmware version is an early one that had some bug.Any suggestions or theories are welcome, and thanks again for the manual. It has allowed me to know what "Should Work".I don't have any schematic or service info, I'll see if there is an EPROM inside, maybe I need a later firmware version.As a hobby, I fix old radios and this signal generator has a sweep function for checking bandwidth and aligning, and the front panel is a bit awkward to use, serial control would be a big improvement.

author: thm_w
author_rank: Super Contributor
timestamp: January 23, 2024, 11:22:51 pm
content: Yeah 9600 or less should work, according to the manual.The cable pinout shows a straight through RS232 connection, so make sure you are not using a null modem cable.Make sure minicom or whatever app is set to send CR+LFhttps://arstechnica.com/civis/threads/telling-minicom-to-send-cr-lf.566236/

author: richsf
author_rank: Contributor
timestamp: January 23, 2024, 11:27:42 pm
content: I do have a proper RS-232 connection, I did set the CR-LF option in mincomThe G5100 is actually echoing characters.Still puzzled.