How to read internal tags in a task? How to set the specified path?

[yue792069154]

I have a question to ask: How to read internal tags in a task? How to set the specified path?

[kasemir]

Good question. This library is just like the original C version in that it sends symbol paths with the read/write requests and there a symbol "ABC" represents a public controller tag. No idea what the path for an internal tag would be, also not sure if the PLC would return data for internal tags.

[yue792069154]

Thank you. I have another question that I need your help with:

For example, the label name defined by PLC is "REALArrayValue", and the data type is REAL[1000,100].

When using the function readTag ("REALArrayValue", 1000), only data indexed to 123 can be read, and data above 123 cannot be read. How can I write it to read data indexed to 124, 125, 126, and above normally?

When I used readTag ("REALArrayValue [1] [1]"), I reported an error as follows:

etherip.data.CipException: Status: 0x05 [Path destination unknown, The path is referencing an object class, instance or structure element that is not known or is not contained in the processing node. Path processing shall stop when a path destination unknown error is encountered.] - Extended: 0x00

I earnestly request your help。

Best Regards,
wen Le

[kasemir]

"REAL[1000,100]" will pose two problems.
One, I have no idea how to handle multi-dimensional data, not sure how that describes itself, how to decode etc., so you'd have to figure that out yourself.
Second, there's a PLC buffer limit of around 500 bytes. With a REAL using 4 bytes, and allowing for protocol overhead, you won't be able to read larger than about REAL[100].

[kasemir]

To access a single element of an array, see #23