How do you do the assembly in question with 00 90 99 BB BE EF in the RAM.
And I’m working on modding a game myself with arcade (zilog z80), so I’m having a lot of fun with this. When are you gonna add arcade to the zilog z80 videos list?
2 things.
Re: 2 things.
I have no idea what you mean 'do the assembly' in reference to that short byte sequence.
I dont think that sequence is code... 00 is a no-op, 90 would be sub b, 99 would be sbc c, and so on.
it looks more like bitmap data to me (lots of repetition of the same letters) , but it could be sound, text, or just about anything
I've no plans to cover arcade systems, or any more systems at all for that matter, I've covered all the systems I ever wanted to, and the channel doesn't make enough money for me to spend more time on it.
I dont think that sequence is code... 00 is a no-op, 90 would be sub b, 99 would be sbc c, and so on.
it looks more like bitmap data to me (lots of repetition of the same letters) , but it could be sound, text, or just about anything
I've no plans to cover arcade systems, or any more systems at all for that matter, I've covered all the systems I ever wanted to, and the channel doesn't make enough money for me to spend more time on it.
Chibi Akuma(s) Comedy-Horror 8-bit Bullet Hell shooter! // 「チビ悪魔」可笑しいゴシックSTG ! // Work in Progress: ChibiAliens
Interested in CPU's :Z80,6502,68000,6809,ARM,8086,RISC-V
Learning: 65816,ARM,8086,6809
Interested in CPU's :Z80,6502,68000,6809,ARM,8086,RISC-V
Learning: 65816,ARM,8086,6809
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Re: 2 things.
00 is a no-op, 90 would be sub b, 99 would be sbc c, and so on.
How do you tell what that means? that right there.
How do you tell what that means? that right there.
Re: 2 things.
Ok, before you try to do anything with disassembly / Game modding , you need to start from the basics and learn to program your own little projects in assembly. I don't mean a little bit, I mean you need to be very good at it.
I've been doing Z80 assembly for 7 years now and I would only consider myself barely able to do disassembly (taking apart a rom file). My philosophy for disassembly is if you couldn't attempt to write it yourself, you're not going to be able to take it apart and figure out what it does.
As for your specific question, each command converts to one or more bytes, so I simply looked up the bytes in your fragment in my cheatsheet (link below)... but you can't know what the bytes are without knowing everything else in the program code - as I said, I doubt they are actually code at all, and there's no way to be 100% sure without knowing what everything within the program does - it's like a jigsaw puzzle, sudoku or those picross things - you don't know for sure what your looking at until you've worked out all the other pieces.
I recently disassembled a z80 speech synthesizer, and there were data bytes mixed in with the code - I mean 60 bytes of code, 4 bytes of unrelated data, and another 60 bytes of code. You had to work out every line of code to figure out what was going on, and I could only do that because I've written dozens of my own programs, including my own sound generation software for the same platform - so I knew what kind of code to expect.
https://www.chibiakumas.com/book/CheatS ... ection.pdf
I've been doing Z80 assembly for 7 years now and I would only consider myself barely able to do disassembly (taking apart a rom file). My philosophy for disassembly is if you couldn't attempt to write it yourself, you're not going to be able to take it apart and figure out what it does.
As for your specific question, each command converts to one or more bytes, so I simply looked up the bytes in your fragment in my cheatsheet (link below)... but you can't know what the bytes are without knowing everything else in the program code - as I said, I doubt they are actually code at all, and there's no way to be 100% sure without knowing what everything within the program does - it's like a jigsaw puzzle, sudoku or those picross things - you don't know for sure what your looking at until you've worked out all the other pieces.
I recently disassembled a z80 speech synthesizer, and there were data bytes mixed in with the code - I mean 60 bytes of code, 4 bytes of unrelated data, and another 60 bytes of code. You had to work out every line of code to figure out what was going on, and I could only do that because I've written dozens of my own programs, including my own sound generation software for the same platform - so I knew what kind of code to expect.
https://www.chibiakumas.com/book/CheatS ... ection.pdf
Chibi Akuma(s) Comedy-Horror 8-bit Bullet Hell shooter! // 「チビ悪魔」可笑しいゴシックSTG ! // Work in Progress: ChibiAliens
Interested in CPU's :Z80,6502,68000,6809,ARM,8086,RISC-V
Learning: 65816,ARM,8086,6809
Interested in CPU's :Z80,6502,68000,6809,ARM,8086,RISC-V
Learning: 65816,ARM,8086,6809