And hoping that the new format (“.sdc1”) could be recognized. But when I request to open such a file, it always receives ERROR: <function ChirpMain.open_file at 0x10cf2c540>: Unknown file format With no indication of exactly where or what I’ve done to the CHIRP. There’s nothing in stdout but that! I had thought that log messages had been swallowed somehow. I was wrong: apparently there are none.
It's hard to say without seeing your code, but... did you make your match_model() also indicate that those files match?
So, what IS the “correct” way to register a second file format? Since the SD-card image is simply the radio memory (without the CHIRP prefix,) it’d seem to be a snap to fake or ignore the prefix and put the memories into the correct locations in CHIRP.
I'm not sure what "CHIRP prefix" you mean exactly. There's a "metadata footer" that chirp adds to image files, but most drivers are (should be) 1:1 with the memory mapping of the radio until the end of memory and the metadata footer starts.
--Dan