Does anyone know, why a string variable takes one bytes more in ODEntries[] array, than it is defined in code?

I have a CANopen OD object, which is four characters long. Like this: variableName:STRING(4):='ABCD'.

But in ODEntries[] array its length is 5 (ODEntries[].wLen=5). Why is it like this?

I would like to read this object by expedited SDO, and now it doesn't fit in four bytes. Damn.

And I'am working with CoDeSys 2.3.9.4

I am not anywhere where I can test it but in most programming languages a sting will have a null character (0x00) as a deliminator so that the processor knows where the string ends.

Can you move the object character by character? Whatever is reading it would have to know that it doesn't contain a null delimiter but it should be possible.

Yes, it is a NULL character, the fifth one I mean.

So, it looks like the OD needs to have that extra place too, to have the memory organized. It works if I manually set the ODEntries[].wLen=4. Then I can send it by expedited SDO. Or maybe just limit the object to 3 characters.

Thanks nOrM!

If you declare an array as array[4] the size will be 5 (0-4).

It is not an array. It is a STRING type variable, with length 4.

But wait a moment, does STRING(4) mean same as an ARRAY[0..4] OF BYTE, when thinking it with memory space needs?

Wasn't The ODEntries[] an array.

I made an declaration yesterday with STRING[255] it's became 256 in length.

ODEntries is an ARRAY OF STRUCT.

But that was a valid test, thanks!