Problem with VISA Read

[Фарах]

hello!

i am working on interface composed of master and 2 slaves based on protocol rs-485

firstly i did simple example for read-write serial communication and i got this error

Error -1073807339 occurred at VISA Read

i installed all the drivers for my version and problem hadn't solved

please help me

i have a labview 2018 version on win-10 64bit

thanks alot

[Bob_Schor]

The most likely reason for the Error is that there is an error in the LabVIEW Code, which you failed to post.  I'm going to guess that you used Bytes at Port, but that's only a guess.  There may well be a different Error.  Do you know your hardware is working and that you know how to communicate with it using VISA?  [Have you tested it with MAX]?

Bob Schor

[Фарах]

thnx Bob for reply..

no i didn't use bytes at ports..

firstly i am working on simulation this system before implementing it

i have a model in proteus and hex code written on codevisionavr and the labview

[RavensFan]

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@Фарах wrote:

thnx Bob for reply..

i have a model in proteus and hex code written on codevisionavr and the labview

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I don't know what that means.

Have you read the manual for your device that explains the communication protocol?

Your picture shows you sent a command "farah".   That seems like a very oddly named command.  Are you sure about that?

But what concerns me is that it looks like that is all you send and that you didn't sent a termination character such as a linefeed or carriage return.   Most communication protocols that rely on ASCII readable characters employ a termination character that is sent so the device know when it received the entire command, and returns a response ending with one so you know when you've received the entire response.  Since it doesn't look like you have one at the end of "farah", then the device is probably sitting there waiting for the end of the command, and never returns a response causing your VISA Read to timeout after 10 seconds.

[Фарах]

Mr.Bob i think the problem not with termination characters..

i  also tried the ready examples in labview and i got the same error

[RavensFan]

I'll repeat:

"Have you read the manual for your device that explains the communication protocol?"

[Фарах]

yes

[RavensFan]

Did it tell you anything?

Is "farah" a valid command?  And what is it supposed to do?  Are you supposed to send a termination character, either carriage return or linefeed?