Quote from: names_are_hard on June 18, 2021, 05:33:01 PMThere was some discussion in https://chdk.setepontos.com/index.php?topic=13773.10
I seem to recall CHDK / srsa already knew this, from some other thread, but I couldn't find it and there were no details.
QuoteAFAIK the earlier "dual digic" ran a separate firmware on each CPU, see https://magiclantern.fandom.com/wiki/7D_internals and https://web.archive.org/web/20130309115612/http://www.magiclantern.fm/whats-new/104-releases/140-first-7d-alpha-released
I've only confirmed this on 200D. I'd expect all Digic 7 and 8 to be similar. Maybe the dual processor Digic 4, 5 and 6 will use a similar API? Maybe not.
Single Digic 6 (on P&S at least) has a somewhat similar situation: "Omar" is another Cortex R4, similar but not identical to the main core, which runs its own stripped down instance of DryOS. It's not too hard to run code there, but obviously synchronization would be more complicated https://chdk.setepontos.com/index.php?topic=11316.msg119473#msg119473