Search found 11934 matches

by tokumaru
Wed Jan 27, 2021 7:54 am
Forum: Newbie Help Center
Topic: Palettes conflict with simple background.
Replies: 2
Views: 99

Re: Palettes conflict with simple background.

Since you don't have any graphics in yet, the only color you're gonna see is color 0, the background color (unless you point the VRAM address at specific palette entries, in which case the PPU will render that instead of the background color - this is a little quirk of the NES). This is the color yo...
by tokumaru
Tue Jan 26, 2021 12:28 pm
Forum: Newbie Help Center
Topic: Pausing during NMI execution.
Replies: 6
Views: 156

Re: Pausing during NMI execution.

Just to be clear, the drawbacks of constantly enabling/disabling NMIs I mentioned above are: 1- Unwanted NMIs: if you happen to enable NMIs while the vblank flag is set, an NMI will fire immediately, not aligned to the beginning of vblank, which can throw off the timing of your NMI handler, causing ...
by tokumaru
Tue Jan 26, 2021 11:17 am
Forum: Newbie Help Center
Topic: Pausing during NMI execution.
Replies: 6
Views: 156

Re: Pausing during NMI execution.

If you don't return from the NMI handler in time (1/60 of a second), another one will fire and interrupt that one, and if the second one too doesn't return in time, another one will fire and they'll keep piling up until the stack overflows. Actual games will not pause by stalling the CPU, they'll st...
by tokumaru
Fri Jan 22, 2021 1:43 pm
Forum: Newbie Help Center
Topic: Problem with "wait until the user press START"
Replies: 3
Views: 229

Re: Problem with "wait until the user press START"

I checked your code and the program is simpler than I expected (there isn't an actual game loop yet), but you're indeed not waiting any time between detecting the first keypress and the second, meaning you'll blast through the blue state so fast that you don't even have time to see it. The quickest ...
by tokumaru
Fri Jan 22, 2021 1:20 pm
Forum: Newbie Help Center
Topic: Problem with "wait until the user press START"
Replies: 3
Views: 229

Re: Problem with "wait until the user press START"

Not having looked at the code (pardon my laziness), I assume that you're not frame-limiting your program, which means that when you press start it blasts trough the blue state and reaches the red state before it has time to display the blue. If that's the case, there are two things you can do: 1- Fr...
by tokumaru
Fri Jan 22, 2021 11:58 am
Forum: NESdev
Topic: Was there an NES expansion chip like SA-1
Replies: 31
Views: 1159

Re: Was there an NES expansion chip like SA-1

Yeah, you can do all kinds of little background enhancements - or even big background enhancements, since you can implement completely new versions of the name/attribute/pattern tables, with lots of tiles, flipping and finer palette selection - but that still doesn't do squat for sprites or the pale...
by tokumaru
Fri Jan 22, 2021 10:23 am
Forum: NESdev
Topic: Was there an NES expansion chip like SA-1
Replies: 31
Views: 1159

Re: Was there an NES expansion chip like SA-1

Yeah, but there's still quite a bit of color clash if you try to incorporate moving objects into that layer, and you're still limited to 4 palettes overall, so that doesn't really do much to solve the 2 problems I mentioned (sprite and palette counts), which I consider to be the biggest limitations ...
by tokumaru
Fri Jan 22, 2021 4:00 am
Forum: Newbie Help Center
Topic: Set a bit, clear a bit.
Replies: 6
Views: 274

Re: Set a bit, clear a bit.

That's correct.
by tokumaru
Fri Jan 22, 2021 3:58 am
Forum: NESdev
Topic: Was there an NES expansion chip like SA-1
Replies: 31
Views: 1159

Re: Was there an NES expansion chip like SA-1

I don't see much benefit in improving the CPU side of the NES when its PPU is much more of a bottleneck in terms of how complex its games can be. The small number of sprites and palettes are what hold the NES back the most IMO, and neither of those can be improved by extra hardware on the cartridge....
by tokumaru
Thu Jan 21, 2021 9:44 am
Forum: Newbie Help Center
Topic: Nerdy Nights basics: role of the "bank" code
Replies: 7
Views: 226

Re: Nerdy Nights basics: role of the "bank" code

My recollection was that NESASM did not allow that Oh, I meant that the CPU will seamlessly cross from one bank to the other, not the assembler. Sorry for not making that clear. (though if you were really careful, you could put a .bank directive in the middle of a routine, possibly padded with NOPs...
by tokumaru
Thu Jan 21, 2021 5:52 am
Forum: 2020 NESdev Competition
Topic: Upsad Down - puzzle game with a ball crush
Replies: 5
Views: 343

Re: Upsad Down - puzzle game with a ball crush

Fadest wrote:
Thu Jan 21, 2021 5:41 am
(color $2D is set et $10 for example)
The $xD column of the NES palette is weird... Not all versions of the PPU have those grays, and color $0D is the infamous "blacker than black", which can cause trouble on some TVs. Generally speaking, it's better to avoid column $xD altogether.
by tokumaru
Thu Jan 21, 2021 5:09 am
Forum: Newbie Help Center
Topic: Nerdy Nights basics: role of the "bank" code
Replies: 7
Views: 226

Re: Nerdy Nights basics: role of the "bank" code

Each bank has a maximum capacity of 8 KB. Yes. Keep in mind that this is a NESASM thing though, it's not a universal NES or 6502 thing. Other 6502 assemblers can have variable bank sizes, or not even have the concept of banks at all. This is just the solution NESASM uses to control the size of the ...
by tokumaru
Thu Jan 21, 2021 4:56 am
Forum: Newbie Help Center
Topic: Why can't I see the palette in the memory debug?
Replies: 2
Views: 130

Re: Where are the Palette actually stored?

The NES has 2 separate memory spaces, one for the CPU and one for the PPU. $3F00 on the CPU memory is just a mirror of PPU registers $2000-$2007, which repeat over and over until $3FFF, so you don't want to mess with that. When you write data via PPU registers $2006 and $2007 you're actually sending...
by tokumaru
Thu Jan 21, 2021 4:36 am
Forum: Newbie Help Center
Topic: Nerdy Nights basics: role of the "bank" code
Replies: 7
Views: 226

Re: Nerdy Nights basics: role of the "bank" code

NESASM is a little quirky in that it requires these .bank directives to control the sizes of the ROMs it generates. Just think of each NESASM "bank" as a chunk of 8KB, and use as many banks as you need to make your ROM as big as you need it to be. In this example, banks 0 and 1 form the 16KB of PRG-...
by tokumaru
Tue Jan 19, 2021 6:58 am
Forum: NES Hardware and Flash Equipment
Topic: Converting PAL to NTSC using Famicom
Replies: 11
Views: 951

Re: Converting PAL to NTSC using Famicom

Not exactly a bug, more a "didn't yet occur to them that developers might want that" That's kind of a weird update to make once you already have lots of consoles out there with the old behavior, since developers will not be able to take advantage of the feature because of that. Unless they consider...