nesdev.org

Ramsis wrote:

Optiroc wrote:That would be 8 master cycles per byte for DMA (ie. 1 cpu cycle at 2.68MHz), while mvn/mvp takes 7 cpu cycles per byte.

Thanks for NOT READING my post at all.

Sorry for clearing things up!

Detailed info on timing: http://wiki.superfamicom.org/snes/show/Timing

That would be 8 master cycles per byte for DMA (ie. 1 cpu cycle at 2.68MHz), while mvn/mvp takes 7 cpu cycles per byte.

There's also bass, xkas, and asar, for those who want to be able to move the direct page around. Not the slightest impossible with ca65. Just use the z:-modifier and you're set. Here (in the SFX_INIT_mmio function) I do the canonical PPU initalization using direct page addressing with some helper m...

I recommend you take a look at Undisbeliever's projects on github to learn how to structure a project using ca65 and Make.

Instead of shying away completely by git – it can be a bit overwhelming at first – I suggest you try a basic local workflow first. Branches and remotes (ie. github) can come later. Make a copy of a local project directory and add it to a git UI client. SourceTree is a good pick, and it's not tied to...

How is it possible to load both at the same time? By not loading both at the same time. What I do in my SPC loader is to divide the loading process into two stages: Stage 1: a routine is copied to the first page of SPC RAM, which will receive data going into the SPC RAM range $00f8..$ffff. Stage 2:...

Blargg has that covered. The final stages of how the CPU state is transferred is really rather masterful... I can't find the original source right now, but I've adapted his code to my SNES framework here: https://github.com/Optiroc/libSFX/blob/master/libSFX/CPU/SMP.s (with some other relevant snippe...

I seem to remember that one of the Yamaha synths was patch-compatible with the YM2612 in the Genesis. Which was it? Because if someone sampled that synth in a Super NES game, then Genesis does nothing that Nintendon't. It was patch-compatible with the YM2414, used most famously in Yamaha TX81Z. Als...

Personally I prefer being verbose with labels (as well as function names, properties and what-not in high level languages). I left short cryptic names behind when I left the C64 with Turbo Assembler (fitting the editor/assembler and the code produced on the same 64KB machine sounds like complete mad...

Seems to me that the "suspicious" warning should be implicitly silenced in 65816 mode. Maybe we could add a "dp:" address operator that forces one byte operand without complaints?

UnDisbeliever wrote:I personally have no problem with +/- labels and do use them with them with other processors. I'm not using them in my SNES projects because ca65 doesn't fully support them.

Out of curiousity: what do you miss from ca65's implementation of unnamed labels?

I recently did an LZ4 decompressor for SNES, with a bit different goals than the brutaldeluxe version. Runs from ROM and no limits on source/destination alignment/banks. LZ4 has a very nice trade-off between complexity and speed (ie. as simple as it can possibly get!). I'll probably add another vers...

Just thinking though, has there ever really been a publicized 2D engine? There are plenty of 3D ones, like all the id ones that were just listed. The problem with 2D is that it's much easier to make from scratch (sometimes to the point of being outright trivial) so nobody bothers. 3D has a lot of a...

Being a huge fan of Sega's "super scaler" tech (and similar) since it was invented, I've always been fond of games/hardware that defy the pixel grid and go crazy with its sprites and backgrounds. Hotline Miami was a perfect psychedelic loveletter to that aesthetic for me. But I agree that ...

I guess what I could do is I load from the table full of table addresses indexed by x, transfer the accumulator to x, (that's the value of the address for the table, and I won't need x again) and then index $0000 in ram, so I'm reading what I just indexed, if that makes sense. ldx Whatever lda Tabl...