Search found 349 matches

by ulfalizer
Sun Dec 01, 2013 7:43 am
Forum: NESemdev
Topic: Original Mario Bros bug on my emulator?
Replies: 141
Views: 27035

Re: Original Mario Bros bug on my emulator?

The overhead of the non-emulation parts seems negligible in comparison by the way. Rewinding is just copying a few megs worth of data per second at most - most of it in contiguous chunks - which is nothing on a modern system. Should be very cheap even if some compression is added. Stuff like hardwar...
by ulfalizer
Sun Dec 01, 2013 6:58 am
Forum: NESemdev
Topic: Original Mario Bros bug on my emulator?
Replies: 141
Views: 27035

Re: Original Mario Bros bug on my emulator?

Hadn't actually tried running the emulator as fast as possible in a while, and it seems to manage 7-8x speed on one core despite ~37% CPU usage being reported for 1x. So yeah, complicated prediction and catch-up might have gotten pretty moot for modern desktop systems. :| Currently I've implemented...
by ulfalizer
Sat Nov 30, 2013 3:15 am
Forum: NESemdev
Topic: Original Mario Bros bug on my emulator?
Replies: 141
Views: 27035

Re: Original Mario Bros bug on my emulator?

Hadn't actually tried running the emulator as fast as possible in a while, and it seems to manage 7-8x speed on one core despite ~37% CPU usage being reported for 1x.

So yeah, complicated prediction and catch-up might have gotten pretty moot for modern desktop systems. :|
by ulfalizer
Fri Nov 29, 2013 2:39 am
Forum: NESemdev
Topic: Nesalizer WIP on github
Replies: 11
Views: 5170

Re: Nesalizer WIP on github

Good to hear!
by ulfalizer
Fri Nov 29, 2013 1:57 am
Forum: NESemdev
Topic: Nesalizer WIP on github
Replies: 11
Views: 5170

Re: Nesalizer WIP on github

How do I use the rewind function? Sound seems very stable so far, yeah. Hold R . I used MinGW. I'll provide a patch tomorrow some time. I just used SDL timing stuff as a quick crutch to get it working, but the proper way to do it for better accuracy would be to use the Windows performance counter, ...
by ulfalizer
Fri Nov 29, 2013 1:25 am
Forum: NESemdev
Topic: Nesalizer WIP on github
Replies: 11
Views: 5170

Re: Nesalizer WIP on github

What environment did you use by the way? Cygwin? If you have a patch ready I could add it along with some instructions in the README for a Windows build. :)
by ulfalizer
Fri Nov 29, 2013 1:21 am
Forum: NESemdev
Topic: Nesalizer WIP on github
Replies: 11
Views: 5170

Re: Nesalizer WIP on github

Good work! Playing Mega Man 2. My main box here is Windows so I had to do a little hacking around in the code, especially the timing code since there is no clock_nanosleep or timespec in Win32... but all seems good. Thanks, and cool that you took the time to port it :beer:! I suspected there wouldn...
by ulfalizer
Fri Nov 29, 2013 12:23 am
Forum: NESemdev
Topic: Nesalizer WIP on github
Replies: 11
Views: 5170

Re: Nesalizer WIP on github

Now supports rewinding, and also does a proper reversal of the audio as a gimmick. Thanks to Blargg for helping me find a neat way to do this with blip_buf! A demonstration is available on Youtube . It slaughters the video quality a bit, so I also put it on Dropbox . I picked a game where I was sure...
by ulfalizer
Wed Nov 27, 2013 9:55 pm
Forum: NESemdev
Topic: Video encoding formats/libraries
Replies: 7
Views: 2685

Re: Video encoding formats/libraries

The most versatile choice is probably the ffmpeg library, but there's a hell of a learning curve to it. I've used it in a project before, and even simple decoding took a while to figure out. Like, a couple days. If you're just going to target Windows, check out the DirectShow or VFW APIs for encodi...
by ulfalizer
Fri Nov 22, 2013 8:01 am
Forum: General Stuff
Topic: Console ports that are better than their arcade counterpart
Replies: 19
Views: 5161

Re: Console ports that are better than their arcade counterp

Haven't played the arcade version, but just from looking at Youtube videos the console version of Punch-Out!! seems superior. The larger player and wireframe makes things too cluttered in the arcade version.
by ulfalizer
Tue Nov 19, 2013 2:44 pm
Forum: NESemdev
Topic: 6502 Illegal Opcodes
Replies: 29
Views: 8528

Re: 6502 Illegal Opcodes

Just tested Visual6502 and SXA, 9E doesn't increment that high byte of the argument by 1. Visual6502 DataBus = (X & ((temp >> 8) + 0)); What we are told DataBus = (X & ((temp >> 8) + 1)); What's temp there? If it's the target address (after the high address byte has been corrected), then it's what ...
by ulfalizer
Tue Nov 19, 2013 2:24 pm
Forum: NESemdev
Topic: 6502 Illegal Opcodes
Replies: 29
Views: 8528

Re: 6502 Illegal Opcodes

I just threw this in visual 6502: LDX #$FF LDY #$80 .byte $9E, $80, 0 And it stored 1 to $0100, and took 5 cycles. I then threw this is visual 6502: LDX #$FF LDY #$40 .byte $9E, $80, 0 And it stored 1 to $00C0, and took 5 cycles. So ... dunno?? Looks correct. Both the value (of X in this case) and ...
by ulfalizer
Tue Nov 19, 2013 1:58 pm
Forum: NESemdev
Topic: 6502 Illegal Opcodes
Replies: 29
Views: 8528

Re: 6502 Illegal Opcodes

The behavior of 9C and 9E depends on whether you get a page crossing or not, see viewtopic.php?f=3&t=3831&start=30#p113343 . Should probably add to the wiki. :?
by ulfalizer
Tue Nov 19, 2013 10:24 am
Forum: NESemdev
Topic: 6502 Illegal Opcodes
Replies: 29
Views: 8528

Re: 6502 Illegal Opcodes

And yeah, it would be nice there were agreed-upon mnemonics. I probably have a mix of them from different sources.
by ulfalizer
Tue Nov 19, 2013 10:19 am
Forum: NESemdev
Topic: 6502 Illegal Opcodes
Replies: 29
Views: 8528

Re: 6502 Illegal Opcodes

Another document you should be aware of is http://www.ffd2.com/fridge/docs/6502-NMOS.extra.opcodes . I used that one along with the one you linked when I implemented the unofficial opcodes. IIRC, the 6502-NMOS.extra.opcodes version tends to be correct for instructions where they differ. The instruct...