Instrument Control (GPIB, Serial, VISA, IVI)

cancel
Showing results for 
Search instead for 
Did you mean: 

How to send commands and data upon request

Hello guys, 

I have gpib-usb-hs+ module and I am required to send the following commands and data in the following sequence:

MLA18

{DATA} (6 BYTES)

UNL

MTA18

{DATA} (5 BYTES)

UNT

 

I need this exact sequence with no UNL or UNT at the beginning or the end where they are not a must.

Currently each time I send MLA my program sends automatically send UNL.

I have tried to use c# library and ATEasy programming.

 

Would be very glad to hear your opinion on this issue).

0 Kudos
Message 1 of 5
(126 Views)

I don't know exactly what UNL, UNT or MLA is, but assuming these are some constants related to Newline, line feed and based on your description of usage with GPIB.

 

These might be useful - https://www.ni.com/en-us/support/documentation/supplemental/06/termination-characters-in-ni-visa.htm...

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000YHpGCAW&l=en-US

https://forums.ni.com/t5/Instrument-Control-GPIB-Serial/Default-GPIB-termination-character/td-p/2425...

 

With additional details, the above links may be irrelevant

-Santhosh
Semiconductor Validation & Production Test
Soliton Technologies
0 Kudos
Message 2 of 5
(82 Views)

Thank you for your reply. 

The links you sent are talking about various ending char, in my case the NI module adds a termination command (UNL-Unlisten) before every MLA(My listen address).

I need to find a solution to bypass this automatic addition. 

0 Kudos
Message 3 of 5
(69 Views)

This is the original IEEE-488 configuration with the very low-level communications.

> To SEND commands:

  • Setup Talk address (for controller)
  • Unlisten ('?')
  • Listen Address (particular instrument)
  • Data/Address Bytes

> To Hear Responses:

  • Set Listen Address (for controller)
  • Setup Talk Address (for particular instrument)
  • Receive Data/Address Bytes
  • Unlisten ('?')

Repeat for next instrument or continue to listen for further responses. 

 

Most of these low-level commands are handled within the simpler SCPI command sets. 

Help the Community (and future reviewers) by marking posts as follows:
If it helped - KUDOS
If it answers the issue - SOLUTION
0 Kudos
Message 4 of 5
(51 Views)

I 100% agree with you, yet in my case I want to send MLA without UNL being sent automatically/by itself before MLA.

 

I need a clear package of 

MLA 

* DATA*

UNL 

MTA

* DATA*

UNT

 

no unnecessary addons

 

0 Kudos
Message 5 of 5
(27 Views)