gpib

[kstipe]

ok, now back to the question at hand, why won't the instument take my commands? From the manual I have taken the commands that is says it will accept and I have tried putting them into the communicate with instrument pannel. when I click write nothing happens other than the IBCNTL number changing to the number of characters I have in my command. (not very helpful)    When I click read it errors out.

Can communicate with instrument pannel actually send commands? or is it just used to test whether the program is sending and recieving communications?

I also am confused as to what you had me to to configure the GPIP and the \r. I just don't really understand that.  

Thank you for dealing with my lack of knowledge.

[Dennis_Knutson]

That command is not supposed to return data so the read will of course time out. Looking at the manual, only those commands that have a ? prefix will return data. Those are queries and you can click the query button instead of a separate write and read. Just try the ?ID query.

EOS stands for end-of-string and each command must be terminated with the correct character for the instrument to recognize it. The EOS for this is the carriage return character. You must configure EOS in MAX or click the EOS button in the communicator. Otherwise, the only thing sent with the command is the current GPIB standard EOI (end-or-identify) control signal.

The VISA interactive control makes it a bit easier (in my opinion) since you can directly type the \ code equivalent of a carriage return into the write string. When you open it, the default command there is *IDN?\n. You would need to change it to ?ID\r in order to send the correct command terminated with a carriage return (the \r)

There are numerous GPIB tutorials available and you want want to review some of them. Normally, it's much easier to establish control. Your instrument does not comply with IEEE-488.2. IEEE-488.2 said that instruments would only require EOI and standarized some commands such as *IDN? to return the instrument's identity.

[kstipe]

So it turns out that the gpib to serial converter we were going to get only works from a serial port from your computer to a GPIB port to your instrument, so GPIB is out.

Thank you for all of your help. I will be opening another thread about serial once I start to get to know IT a little better.

Thanks again.

[Dennis_Knutson]

Since the instrument you talked about does have a GPIB interface, I don't understand your comment. Though using a serial to GPIB is not something I would recomend anyway. A real GPIB controller is the best choice.

[kstipe]

the SP-150 does have both, but I am just learning on the SP-150 in order to learn labview and (serial) for a custom machine that I need to program for later on.  the SP-150 was just a starting point to teach myself on, but since the other machine doesnt have GPIB, there in no point in learning it at this time

[kstipe · Accepted solution]

What ended up working in the end was updating from 8.x to 2011 labview. I believe the problem I had was when I would type in the command it would read "250.0 NM"  where as in 2011 when I typed it in it auto corrected it to "250.0\sNM"  To my knowledge that was the only thing going wrong. I could be wrong though.