Search found 177 matches

by albailey
Fri Dec 05, 2008 9:10 am
Forum: NESemdev
Topic: Strategies when developing an emulator
Replies: 5
Views: 3620

Strategies when developing an emulator

I've been passively working on a NES emulator. I find it a very useful way to expand on my knowledge of NES programming. I've read documents here and on the wiki,but I am essentially still in the design phase. (I have the cpu done, and am ready to start the ppu) I have some questions for the people ...
by albailey
Mon Nov 17, 2008 9:29 am
Forum: Newbie Help Center
Topic: Im back after a big break
Replies: 4
Views: 2351

There's lots of good 2D stuff in the graphics gems series
http://tog.acm.org/GraphicsGems/gems.html

I'll admit that I've never made reference to this for my NES programming, but I used to refer to it alot back in my ray-tracing days.

Let me know if you find anything good in there.

Al
by albailey
Fri Nov 07, 2008 11:16 am
Forum: Newbie Help Center
Topic: expendable sports games
Replies: 12
Views: 5067

I'd also suggest Bootgod's site http://bootgod.dyndns.org:7777/ You'll notice that 10 Yard Fight is NROM-256 (because the PRG is 32K I assume) so it is ideal. On the other hand, Baseball is an NROM game but only has a 16K PRG and is available as NROM-128 so you probably would not want to use it sinc...
by albailey
Wed Nov 05, 2008 6:56 am
Forum: NESdev
Topic: Give my game a try
Replies: 37
Views: 19731

I also think it would be a good one to add to Garage Cart.
Al
by albailey
Wed Nov 05, 2008 6:53 am
Forum: NESdev
Topic: Fading the palette to black
Replies: 20
Views: 6937

There's one little gotcha.
You need to do a special check to prevent setting 0x0D (blacker than black). It really only matters if you plan to run on a real NES on a real TV since I dont think emulators emulate the 0x0D insanity.
Otherwise, yes drop16, then on the last step set to 0x0F

Al
by albailey
Mon Nov 03, 2008 11:06 am
Forum: Newbie Help Center
Topic: Ok, what did I do wrong here?
Replies: 19
Views: 7872

The only time I've ever seen people need to do anything complicated for NROM is if they are using an NROM 128 cart and are trying to put a 32KB chip in it. I'd rather save the effort and use a different donor cart. At least with NROM theres tons of cheap ones to be found (baseball, 10 yard fight, gy...
by albailey
Fri Oct 31, 2008 7:49 am
Forum: NESdev
Topic: My first foray into making cinema displays
Replies: 39
Views: 10445

I think it looks good, and I like the style of graphics.
How did you do that scroll part. Are some of those sprites?

Al
by albailey
Fri Oct 31, 2008 6:22 am
Forum: Newbie Help Center
Topic: 256 Byte RLE Decompression Routine
Replies: 12
Views: 4306

Roth, if you're making use of my nes dev tools you can use the Screen Layout Tool, and select RLE compression when saving the nametable. It uses Apple's packbits algorithm. I'll upload the assembly subroutines in that thread for making use of it.

Al
by albailey
Mon Oct 27, 2008 6:56 am
Forum: NESdev
Topic: Give my game a try
Replies: 37
Views: 19731

I like it, and I especially like the graphic style.
Al
by albailey
Tue Oct 21, 2008 6:18 pm
Forum: Newbie Help Center
Topic: EPRom question, but possibly not the one you're used to...
Replies: 13
Views: 4798

I've never had luck cutting traces (or attempting to repair them) but thats me. One of the reasons the instructions sometimes say Hole rather than pin, is that for some boards you are putting a 32 pin eprom where a 28 pin one used to be (for me, I just get a 32 pin donor board). I think some UNROM b...
by albailey
Tue Oct 07, 2008 6:01 am
Forum: NESemdev
Topic: 8KB PRG ROMs
Replies: 16
Views: 7312

So how would you deal with VS Tetris?
Is the bottom 8K mirrored, or the top 8K?
Al
by albailey
Tue Sep 23, 2008 12:36 pm
Forum: NESemdev
Topic: 6502 CPU emulator - Infinite loop running a NES game?
Replies: 12
Views: 4671

In your code: // Starting point where the code is CPU.PC = 32767; Is that the location of the reset Handler?? If not, you should refer to the last 6 bytes in the ROM. Those are 3 important addresses (IRQ, NMI and Reset. Probably not in that order). Start running the program at the reset handler's ad...
by albailey
Sun Aug 10, 2008 9:31 am
Forum: Newbie Help Center
Topic: Question about Sprites and the 8 per scanline "law"
Replies: 4
Views: 3002

Thanks guys.

Al
by albailey
Sat Aug 09, 2008 8:09 am
Forum: Newbie Help Center
Topic: Question about Sprites and the 8 per scanline "law"
Replies: 4
Views: 3002

Question about Sprites and the 8 per scanline "law"

I know from reading the docs, wiki etc.. that there is an 8 sprite per scanline limit. If you hit that $2002 bit 5 is set. According to the wiki, only the first 8 sprites per scanline are used. My understanding is that if you exceed the 8 sprites, a slowdown occurs, and often there is a flicker, sin...
by albailey
Mon Jul 21, 2008 10:50 am
Forum: NESdev
Topic: Video demo of my Columns clone
Replies: 27
Views: 13057

That looks awesome Sivak. Not just the gameplay, but all the other extra effort you put in.
Al