Giuliano Zaro

oh, add the same "debug print" in case 2. This is when P0 is sent periodically

is this message ("test output") what you get in rx_buffer?

and "'P0' complete" where does it come from?

That's not what I meant when I said to print out rx_buffer and also, in case - 4, inside Else you do an unnecessaru sscanf. what I was thinking something...

Since I don't see message: "MMU 1" "MMU - ENABLED" it seems that sscanf or the debug print itself is the issue. I highly suspect sscanf but you may continue...

What you get here is a PC error, not a Marlin fault. Sure system you are using doesn't send a M112?

@ellensp I suspect he has a lcd due to his statement: > The above setup sends Marlin into a boot loop What I don't understandi is that a message before...

I checked and C89 is really old and we are using, as older, c++11 that is year after C89

I don't know where to look at. All seems bring to sscanf, but no real evidence, just suspects. To remove any doubt you may replace sscanf, where `finda` variable is...

Then sscanf is not guilty. No idea how to find where/why marlin hangs, sorry