SpritesMind.Net

Stef wrote:Using signed 8 bits sample permit to keep the quality of 8 bits sample and have only an extra "add $80" instruction.

Which is faster, shift or add ?

You did "ADD reg, #80" on sample data in your code, why is it required ?
I just add two samples together if I use 7-bit unsigned, or do some shifts if I use 8-bit unsigned and then add them together.

I don't like any signed stuff and how can you mix signed stuff easier ?

I don't have the code here so i can't really remember perfectly, but that should give you some tips... what part you don't understand ? Actually most of it. I just figured out a way to improve my code, now I can free one reg (actually 2). Anyway my driver uses 8-bit unsigned samples, with 4 byte he...

RedAngel wrote:Some links:
ADPCM routine
PSG samples

Cool stuff

I looked at your 2ch mixer code, and I looked at it again, and I must say, that I didn't get it

I should have written my Z80 driver friendly, it is basically RAW data, but it has some "header" data in it so it's easy to get all required info on the sample.

ElBarto wrote:Hello, me again
Is it possible to have a blabla section for non-megadrive related topics ?

Good Idea, all the forms I've visited have one

Ok, I'll see tomorrow

I started to write my own 2ch mixer, this time I won't use WAVs but more game friendly format

there's WAVs in the dev kit ?

I'll check it out ... on monday, I have dial up at home and downloading 1MB is pain but to talk about 13MB !

I think I'm going to use some things, you know more advanced stuff than I. I looked at your code, and I think, I could not make it faster.
Is usage of X and Y slower than HL ?

OK, now I see, I prefer to use faster stuff

I knew about XH, XL... but I saw LD DE, (ASDFGH) (<-reg maybe incorrect), I thought that you can only use A or HL (and X, Y) for memory stuff

No No, I meant in 2ch mixing.

Do you know any good doc on z80, I saw some things in your code which I thought cannot be done on z80 that way.