Since I don't use windows and therefore also a TwinCat,
I have been looking for a way to convert my ESI files under Linus and write them to the EEPROM.
I have to say that there is already such a tool in C,
but you can only use it for their hardware.
So I thought I'd write one in Python under the GPL.
it's still in the early stages, but the test data I have is written 1:1 bit-accurately in the same way as the siitool does.
github.com/multigcs/esitool/
