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→Strings -
The **Roland xx looks like a boot banner and is called differently in the firmware. I'm sure that's why it has different start and stop markers. Ditto for the early Version string. Interestingly, the early Version is way at the other end of the addresses in the code. This adds to the DFU / Bank swap theory.
When I finally load the firmware (I still haven't at this point) I spend ages looking for what calls these strings. I find it difficult to navigate but fascinating. It is very difficult to navigate any production firmware disassembly I expect. I have no prior experience, but it seems the firmwareH8300H is kind of a different level, a bit of an oddity. Basically zero xrefsIt's used a lot in Japanese electronics, not so much in Europe I think. I think it's in the Gameboy Advance? One or two strings can be discovered, which have a different call system to the diagnostic strings (the ones I'm most interested in) especially because I have to repair so many subsystems, ICs, and traces.
I don't know at this point that these diagnostic strings are highly likely to be called by the Monitor Version 1.00, which is highly likely a Machine Language diagnostic tool which must operate over UART.
There was actually some DOS software that I had a crack at too which apparently loaded H8 firmware but I never got it to open the file.
== Ghidra - ==
I find Ghidra and compile Dev version for some reason I can't recall. I think so I can load third party CPUs. H8300H is not supported in Ghidra. I find a plugin, https://github.com/shizmob/ghidra-h8-300 and try to compile that and load in Ghidra. It won't compile though -
Later I also tried https://github.com/carllom/sleigh-h8 which I also don't get running in Ghidra -
== Cutter - ==