Ryvius86, I've seen this, and its unfortunately really vague. I was hoping to find undocumented recon, such as someone loading each register, resetting and viewing the registers - on real HW of course.
Let's take for example, the game Rompers on Namco System 1:
the game boots up, and loads stuff into the subcpu's ram & registers, then resets the chips.
If all of the registers of the hd63701 cpu are cleared on reset, boot fails. I know the [somewhat related] hd6309 chip has a "v" register which survives a hw reset - it's even documented. ..but.. info on the hd63701 about these things seems a little lacking
![Sad :(](https://neo-source.com/Smileys/default/sad.gif)
best regards,
- dink