Hi,
I have been trying to get a Rohde & Schwarz CMU-200 Universal Radio Communication Tester over GPIB with the NI GPIB-ENT. The Rohde & Schwarz device is a little unique in that it has multiple secondary addresses and requires you to specify one for it to work. I can succesfully execute the following commands in MATLAB:
>> g = gpib('ni',0,21,'SecondaryAddress',96);
>> fopen(g)
>> query(g,'*IDN?')
ans =
Rohde&Schwarz,CMU 200-1100.0008.02,104806,V4.30
>> fclose(g)
This would be find if I wanted to write my own driver. However, Rohde & Schwarz has a VXIplug&play driver available for use. The MATLAB Instrument Control Toolbox can generate a MATLAB driver from this VXIplug&play driver, but I am required to connect in a different way using a VISA resource string. When I try the following, it fails:
>> d = icdevice('rohdeschwarz_cmu200', 'GPIB0::21::0::INSTR');
Warning: Warnings messages were produced while parsing. Check the functions you intend to use for correctness. Warning text can be viewed using:
[notfound,warnings]=loadlibrary(...)
>> connect(d)
??? The VXIplug&play driver could not connect to the instrument using the specified resource.
If this error is not an instrument error, use MIDEDIT to inspect the driver.
For further investigation, I tried opening a connection to the device using the visa() function in MATLAB, I am unable to query the instrument. Here are the commands I type:
>> g = visa('ni','GPIB0::21::0::INSTR');
fopen(g);
>> query(g,'*IDN?')
??? Error using ==> icinterface.query
VISA: No listeners condition is detected (both NRFD and NDAC are deasserted).
I am not sure what that error message means. However, I tried using the NI Spy tool. A ton of messages were returned, but one in particular stuck out at me:
11. viOpen (0x0007CD78, "GPIB0::21::INSTR", 0, 0, 0x0007CDC0)
Process ID: 0x00000858 Thread ID: 0x00000A68
Start Time: 09:23:07.882 Call Duration: 00:00:00.281
Status: 0x3FFF007D (VI_SUCCESS_DEV_NPRESENT)
It seems as though the secondarry address information has been stripped out of the VISA string. I have a feeling this has to do with a bug in MATLAB. I have been in contact with the MathWorks. However, if anyone on this board could offer their opinions on what the problem may be or any other insights, it would be appreciated!
Thanks.
