R&S CMU200 GPIB Prologix problem - Page 1
Forum section: electronics / rf-microwave

author: om4ik
author_rank: Contributor
timestamp: October 08, 2019, 06:48:42 am
content: HiI am new owner of Rohde Schwarz CMU 200. I want to connect it with PC via GPIB interface but adaptors for GPIB are so expensive so I borrow Prologix USB from my friend. I connect it to PC install sw and then connect to CMU 200 but I havent any luck to communicate with it. I try command id? for testing comunication but no answer. I have got also old Lecroy osciliscope with GPIB port so I connect prologix there and no problem. After send id? Lecroy answer type. When I reconnect it back to CMU 200 no comunication. Adress is also right set.On manual of CMU200 there is wrote remote mode is automaticly set by REN (remote enable) signal on GPIB PIN 17. But on my CMU 200 when I connect GPIB adaptor and try to communicate no remote mode is visible on screen so I thing theres problem with this signal. I am not sure if my CMU has 100% OK GPIB port or problem is on incompatibility with prologix (i heard prologix has problem with R&S equipment). Someone has experience with it ?Thanx Igor

author: Roland_W
author_rank: Contributor
timestamp: October 08, 2019, 05:21:37 pm
content: Hi,Someones have the same problem as you, and on the NI found solution for it :https://forums.ni.com/t5/Instrument-Control-GPIB-Serial/GBIP-Control-using-prologix-usb-converter/td-p/1841041/page/2?profile.language=enYou could find software for testing communication :https://forums.ni.com/t5/Example-Program-Drafts/Prologix-GPIB-USB-Controller/ta-p/3539152?profile.language=en

author: E Kafeman
author_rank: Regular Contributor
timestamp: October 09, 2019, 04:00:39 pm
content: Some Prologix adapter are not fully GPIB compatible. It is more like a slow serialport emulating GPIB.Experimenting with VISA settings and software for different end of command line settings using ";" and both 0d and 0a as terminators can eventual improve.More expensive then Prologix but I do never have problems with NI and HP/Keysight USB-adapters as well as their GPIB-PCI adapters and is normally running 5-6 instruments on same bus and is using full bandwidth for live screen updates with minimal delay.

author: om4ik
author_rank: Contributor
timestamp: October 31, 2019, 06:26:29 am
content: Thanx for replyies. I wrote email to Prologix an they helps me (but answer was all the time in spam). For basic comunitation in terminal with for example *idn? its now OK. The problem was in addressing secondary GPIB (CMU200 has primary and secondary GPIB and secondary GPIB addressing is manually configurable on setup when (if your CMU has many addons) you can address any of this addons to any secondary gpib address. But prologix comunicate with this secondary GPIB with addressibg which is +96 more then address you set on CMU. For example if for RF is selected secondary GPIB address number 1, you must add 96 so in communication with prologix must set address 97. Now it works. Second problem is FRERES (sweep utility by R&S) which probably need VISA standart. I dont know if is possible to use prologix for this application. For today I havent got any lucky.Thanx Igor