Search found 4700 matches

by Dwedit
Tue Nov 22, 2022 4:05 pm
Forum: GBDev
Topic: How do I disassemble a GB rom
Replies: 3
Views: 276

Re: How do I disassemble a GB rom

I'm not familiar with the range of tools for disassembling GB roms, but you can use existing debuggers to see a disassembly of a ROM while it's loaded.

Did any GB emulators adopt the CDL format?
by Dwedit
Mon Nov 21, 2022 9:44 am
Forum: NESdev
Topic: NESRevPlus Issues
Replies: 15
Views: 756

Re: NESRevPlus Issues

When trying to build a CDL file, you can still poke away at RAM values. They might even line up with the original game. Just be careful that you don't trigger a game crash, because that can lead to executing data bytes as code, and messes up the log. I wonder if any assemblers can generate CDL files...
by Dwedit
Sun Nov 20, 2022 10:56 am
Forum: NESemdev
Topic: Nes emulator for playdate?
Replies: 6
Views: 454

Re: Nes emulator for playdate?

Playdate is over 10 times more powerful than the GBA, so it should have no trouble running an optimized NES emulator, but the screen is not well-suited for the task. Usually you would get gray shades by rapidly blinking pixels on and off, but the screen might have too high a response speed for that.
by Dwedit
Sat Nov 19, 2022 7:21 pm
Forum: NESdev
Topic: NESRevPlus Issues
Replies: 15
Views: 756

Re: NESRevPlus Issues

Might be able to get a bit more confirmed code by having each kind of enemy bounce off a wall, get bumped from underneath, and take damage from each kind of enemy. Then maybe attach the CDL file here, so I can see it in mesen.
by Dwedit
Fri Nov 18, 2022 9:12 pm
Forum: NESdev
Topic: NESRevPlus Issues
Replies: 15
Views: 756

Re: NESRevPlus Issues

If you're not familiar with code-data logging, it requires that you play through the game and have all the code get executed and all the data get loaded to get a complete CDL file. Have not confirmed if loading state disrupts a CDL file or not.
by Dwedit
Fri Nov 18, 2022 8:49 pm
Forum: NESdev
Topic: NESRevPlus Issues
Replies: 15
Views: 756

Re: NESRevPlus Issues

Make a Code-Data log (CDL file) before trying to use any disassemblers. FCEUX lets you create one, and Mesen automatically creates one if you open the debugger and press Run.
by Dwedit
Wed Nov 09, 2022 11:50 pm
Forum: NES Music
Topic: Simplest way to integrate an nsf to your game code.
Replies: 19
Views: 744

Re: Simplest way to integrate an nsf to your game code.

If your program is really really simple, you can take an NSF file and write your game so that it doesn't overlap any ROM or RAM addresses, and you call the init and playback routines properly. Only really suitable for very simple demo programs though. You generally don't want to do this, as it is ve...
by Dwedit
Tue Nov 01, 2022 9:25 pm
Forum: NESemdev
Topic: SMB3 Title Screen Problem, Checkered Floor Wobbling
Replies: 6
Views: 561

Re: SMB3 Title Screen Problem, Checkered Floor Wobbling

Maybe some basic logging here... Write down the timestamps of the writes that set up the interrupt and enable it Write down the timestamp that the interrupt fires on, and when the 6502 has completed jumping to the IRQ handler. Write down the timestamps and values of scroll/vram address writes. Times...
by Dwedit
Tue Nov 01, 2022 9:29 am
Forum: NESemdev
Topic: SMB3 Title Screen Problem, Checkered Floor Wobbling
Replies: 6
Views: 561

Re: SMB3 Title Screen Problem, Checkered Floor Wobbling

Make sure you also have timing correct for scrolling (Loopy V and Loopy T updating/incrementing at particular times) https://www.nesdev.org/w/images/default/4/4f/Ppu.svg https://www.nesdev.org/wiki/PPU_scrolling On Dot 256 vertical part of T is incremented, on dot 257, horizontal parts of V = horizo...
by Dwedit
Sun Oct 23, 2022 12:41 pm
Forum: NESdev
Topic: Does 30 fps look too uncanny for a retro style game?
Replies: 16
Views: 1445

Re: Does 30 fps look too uncanny for a retro style game?

Mesen has a code counter, so you can see which code is executed more than the rest. That might be helpful for seeing which functions are executed too often, and could be tightened up.
by Dwedit
Thu Oct 20, 2022 6:15 pm
Forum: NESdev
Topic: SMB1 Hacking
Replies: 33
Views: 3508

Re: SMB1 Hacking

PHX / PHY / PLX/ PLY can be simulated by using A as an intermediate register (see TXA TYA TAX TAY), but what exactly is supposed to be the benefit of porting over the SNES version's code here?
by Dwedit
Tue Oct 18, 2022 6:32 pm
Forum: NESdev
Topic: my sound has stopped working with famitone?
Replies: 3
Views: 435

Re: my sound has stopped working with famitone?

Ram address conflict for variables?
by Dwedit
Thu Oct 13, 2022 3:41 pm
Forum: GBDev
Topic: Game Boy CPU isn't a Z80. What is it?
Replies: 27
Views: 26560

Re: Game Boy CPU isn't a Z80. What is it?

From the GB game developer's perspective, it's so close to a Z80 that people just called it a Z80, or nickname it the "Game Boy Z80". Even though it is missing a lot of Z80 instructions (no IX, IY, etc), and has new instructions that aren't in the Z80 or 8080.
by Dwedit
Mon Oct 10, 2022 10:27 am
Forum: phpBB Issues
Topic: Searching for OAM DMA: To be or not to be?
Replies: 5
Views: 834

Re: Searching for OAM DMA: To be or not to be?

It would probably help to completely remove the PHP session ID from all URLs. That breaks web searches and Wayback machine.
by Dwedit
Sun Oct 09, 2022 6:15 pm
Forum: SNESdev
Topic: How did Square do these effects in Final Fantasy IV?
Replies: 14
Views: 1052

Re: How did Square do these effects in Final Fantasy IV?

I think Mesen-S also has the event viewer.