Re : Re: NI-DEVICE, terminate reads on EOS?

[IaiEng]

I'm using NI-DEVICE version 1.5 for a new product on the XP Embedded operating system.

I'd like a version of NI-DEVICE that will terminate a read and execute the InputQueueEventHandler on an application defined EOS character without an EOI from the bus controller. Any chance I could see this in the very near future (say 2-3 months)?

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[Robert M]

Hi laiEng,

Unfortunately there are currently no plans to release a version of NI-DEVICE with this feature.  Terminating a read without an EOI from the bus controller would not meet 488.2 specifications.  I'm sorry for any convenience this causes.  If you feel this answer does not meet with your expectations and you would like to open a more in-depth discussion, please contact your National Instruments sales representative.

Hope this helps,

Message Edited by Robert M on 09-20-2005 02:22 PM

[IaiEng]

However NI-DEVICE does allow non-compliant IEEE488.2 interfaces using Relaxed Mode. Ins't this request along the same lines?

[GPIB_Guru]

It is one of our ongoing battles to figure out how to correctly implement it. The only bus that it is an issue on is GPIB since USB and Ethernet don't have a concept of character-only termination. The complication comes in that sometimes a NL is an end and sometimes a NL is not an end (if you are in the middle of binary data). Essentially, NI-Device doesn't know the difference. One option is to inform the user that they got a NL and allow them to indicate whether or not it is a proper END. This would require that the users parser be smart enough to understand that it got a binary NL and to inform NI-Device as such.

There are currently no plans to add this (or some other option) to NI-Device, but your request has been noted and will be taken under consideration for future versions of NI-Device.

[IaiEng]

Whay about an unsupported change?

Jason

[GPIB_Guru]

What do you mean by an unsupported change?

[IaiEng]

A change to NI-DEVICE that isn't supported by NI; a one-off version; a custom release.

The other option I see is for me to use the DDK, but my understanding is that the DDK doesn't contain the source code and project files required to build the Windows version of NI-DEVICE.

[NicoTAS]

Hi,

I'm also using NI-Device in a system connected to a 488 GPIB bus. And I encountered the same problem.
I don't know if an issue has been found since the post is one year old, but I would accept any information or advice.

Every messages I receive are MSg_Unterminated and terminating on eos would have been great!

Thanks a lot,

Nicolas

[Robert M]

Unfortunately no changes have been made to NI-Device that address your issue and there are no plans to make the changes.

[NI_Device_user_sb]

Hello, I'm currently working on NI-Device and I encountered the same problem. My purpose is to work with 488.1 and 488.2 controllers and NI-Device capturing all gpib messages. But I found one solution which is not good enough (I think so): It's polling the Input Buffer with functions of C4882::MsgBuffer class like GetMsgLength() and GetBuffer(). This solution is not the best because, if I have only 488.1 messages, it will cause the buffer to be full so it needs to study a specific case. And I suppose it would be a time consuming solution. And that's not in accordance with my project goal.