MAMEWorld Forums - EmuChat - Re: MAME0148 Debugger & Cheats Question

> Debugger Window Frame #3: Top-right frame right of Instruction calls area

They represent the "Instruction calls" (aka opcode and operand) as bytes, a Z80 16 bit jump opcode is represented by C3 and with an operand of $BEEF we have JP $BEEF which we be represented by C3 EF BE (lo/hi byte order on the operand).

> [Cheats Question]
> I would have posted these on Pugsy's forum but new accounts cannot be created right
> now:

It's back on for a few days at least (spambot registrations...)

> Question 1: how does "FFDAE840" relate to "00B5D08"? I can set a breakpoint at
> "FFDAE840" and the debugger stops and the cheat works. However, I don't understand
> how instruction "FFDAE840" relates to "00B5D08". Is "00B5D08" a rom address (since
> this is a ROM cheat)?

The simple formula for this is:
FF800000 + ( 00B5D08 * 8 ) = FFDAE840
That works for all ROM addresses

> Question 2: is there a way to force an instruction call using the cheat system? For
> example: I want to mimic an input press (such as a low-punch button), so I want to
> find the originating (very first) instruction call outside of mame and have the cheat
> system force that call when a condition occurs during a fight.

This may help:

http://www.mamecheat.co.uk/forums/viewtopic.php?f=16&t=2945#p11110

EDIT: That URL may not be what you want, but it's a similar principle

Edited by Pugsy (07/11/13 09:50 PM)