SNPX string writing issues

[JTremblayAGT]

We have variables that describe the direction of an external axis and writing them does not work correctly.

The variable is a string variable of length 2:
$[ProgName]RAIL.DIR = 'Y+'

However, writing to it through SNPX with StringSystemVariables,Write results in only 'Y' being written into the variable.

Also, it seems like the new method Snpx.SetVariable doesn't work with Karel variable.

[Rufus31415]

Is it because you are writing a string of maximum size and there is a problem with the last character?
Or is it because of the character +?

It's possible that Snpx.SetVariable doesn't work for Karel variables. I haven't tried it, but I will at some point. However, it directly uses the SNPX variable write command, which may only support system variables.

[JTremblayAGT]

I just tried and it seems like writing the maximum number of characters is the issue.

[Rufus31415]

I observed what happens at the frame level using Wireshark. Even when reading, the size is truncated. When you read the SNPX documentation, strings are null-terminated : https://cdn.logic-control.com/docs/kepware/Manuals/Drivers/GE/GE%20SNPX%20Driver.pdf . So I think that the trailing zero counts in the string size at the protocol level. I'm afraid there's nothing we can do about it.

[JTremblayAGT]

that's odd since on the controller itself everything works just fine when writing into the strings. I can increase the size of the strings.