hi everyone! as i tried some experiences on over 100 z80-based classic arcade machines (using mame emulator), i started to do the same on 6502-based ones - for now i'm just trying to "poke" something in the display area, but nothing appears there - do anyone can see what is happening there? thanks in advance!
https://drive.google.com/file/d/1CRMMU7 ... G2VXy/view
trying to target classic 6502 arcade machines with xa65
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nitrofurano
- Posts: 4
- Joined: 26 Aug 2018
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leepivonka
- Posts: 168
- Joined: 15 Apr 2016
Re: trying to target classic 6502 arcade machines with xa65
I'm not familiar with MAME, but I'm wondering if you need to arrange for execution to get to your code at $1000.
A hardware Z80 coming out of reset starts executing at $0000, so usually there is ROM at that address with code to run.
A hardware 6502 coming out of reset starts executing where the reset vector at $FFFC & $FFFD points, so usually there is ROM at those addresses containing the vectors & code to run.
Do you need a constant word at $FFFC initialized to $1000?
A hardware Z80 coming out of reset starts executing at $0000, so usually there is ROM at that address with code to run.
A hardware 6502 coming out of reset starts executing where the reset vector at $FFFC & $FFFD points, so usually there is ROM at those addresses containing the vectors & code to run.
Do you need a constant word at $FFFC initialized to $1000?
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nitrofurano
- Posts: 4
- Joined: 26 Aug 2018
Re: trying to target classic 6502 arcade machines with xa65
thanks! i’m really a 6502 newbie, and i had no idea what these vectors are - they are actually mentioned at https://raw.githubusercontent.com/mamed ... circus.cpp - and saying that the last rom placed at $1E00 is mirrored at $FE00 as well, having these vector bytes - now it seems to run fine! thanks again! 