[Rcxemul-discussion] Strange things afoot

[David E. <d.a...@du...>]

I'm hot on the trail of the reason why the firmware won't unlock. I've
discovered that the last time I tried it, there was only one byte in the
entire firmware transferred wrongly. This put the checksum off by 8:

Expected
0xA000 77 79 1E 11 1E 88 1E 00 0D 42 1D 20 47 1E 6E 6A 

Observed
0xA000 77 79 1E 11 1E 88 1E 00 0D 42 15 20 47 1E 6E 6A 

Note that we have 1D in the expected firmware image, and 15 in the
observed. I have no idea why! I've traced through the tons of debug
information that I have and I'm still at a loss. 0x1D is definitely the
value that gets transmitted by the firmware downloader, but 0x15 is
being written.

I'm going to try again to see if it's the same byte that gets written
wrongly. If it is, I'm going to have to trace the receive handler for
that particular byte to see why it's not getting set correctly.