VISA

[Stockholm822]

hii all

i am new user here.. i have created a Random signal and it consist of  2040 pixel each of them has 32 bits.. I wana send this signal via rs232 and wana read the same signal in labview..  to read it i have already solided 2 and 3 pins of rs232 output.. After i send it  i  become always error 74 code ( error occured Unflattern from string) ..why is it so  Can anyone help me..  thank u  best Regards..

[BTC_Admin]

It means that the string you're reading back from VISA is not in a format that can be used to convert it to 2D array of double.

I don't have a RS232 loopback dongle with me right now, but I think your issue is due to termination character (termination is enabled by default in "VISA Configure Serial Port.vi".) Since you have a string with binary data, when you read it back on the other end, the termination character is probably messing up the format. You could disable termination character in VISA configure and see if that fixes your issue.  You seem to have everything else looking correct in that section.

-DP

[crossrulz]

I don't have LabVIEW readily available right now, but I would create an indicator for the string that is being written and the string that is being read.  Then verify the strings are the same.  That would verify that the termination character isn't getting in your way.  But if you are doing binary data, it is best not to use the termination character on your serial port.

Other than that, I would need to look at your conversions.  I've seen some strange attempts and it is kind of picky.

[Stockholm822]

Hii BTC admin and crossrulz i havent comminicated any Signal in labview before.. that is why i can not achieve...  do i have to remove property node at the visa part or ?  thanks

[BTC_Admin]

All you have to do is to connect a FALSE boolean to VISA configure connector that says "Enable Termination Char (T)", as shown in the attached image.

-DP

[Stockholm822]

Hii BTC

first thank u for your answer but  i have enabled thermination Char but i see the same error again...

[crossrulz]

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@Stockholm822 wrote:

Hii BTC

first thank u for your answer but  i have enabled thermination Char but i see the same error again...

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We told you to DISABLE the termination character.  Did you do any other debugging like looking at the strings that were written and read by the VISA functions?

[BTC_Admin]

Good Morning...  You have to disable the termination char.  You mentioned that you have a loopback (pin 2 & 3 connected), so I assumed that you ensured that loopback is fine - but did you communication (perhaps through a terminal program or checking returned string in your vi) to make sure that what you send out on transmit does echo back on receive? Do you see a positive number in "bytes read" indicator on your vi?

-DP

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@Stockholm822 wrote:

Hii BTC

first thank u for your answer but  i have enabled thermination Char but i see the same error again...

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[Stockholm822]

i am so sorry i mentioned disable   and i have tested rs232  there is an example in ni file  i have tried it and it worked  but not with this example which i posted.I think it is difficut...:(

[Stockholm822]

Hiii all i have tried to solve my problem  but i still cant  at first i became a time out error i think i solved it.. at the communication part of rs 232 in the programm i added  timeout and buffer .. now i see error 74 after i run the programm.. how can i solve it   do u have any idea ???

best regards