Search found 256 matches

by tomaitheous
Sat Feb 16, 2008 10:28 am
Forum: Sound
Topic: MOD/S3M player for the MD
Replies: 31
Views: 20333

Did you tested how much it's 'not noticeable' in any audio editor (especially for looped part of instrument), or just assumes that? Maybe you misunderstand. When I said a single sample clipping, I mean one 8bit sample of the total mixed output stream, not an a whole instrument clipping. If you had ...
by tomaitheous
Sat Feb 16, 2008 9:57 am
Forum: Sound
Topic: MOD/S3M player for the MD
Replies: 31
Views: 20333

with no noticeable clipping Clipping is always noticeable if not handled, because in that case output volume jumps from ~max to ~min (or vice versa). To make it not very noticeable it must be handled, i.e. if there was overflow after addition, output value must be corrected (>255 = 255; <0 = 0). Bu...
by tomaitheous
Sat Feb 16, 2008 9:39 am
Forum: Sound
Topic: MOD/S3M player for the MD
Replies: 31
Views: 20333

Four bits gives a value of 0 to 15. The maximum value for 8 bits is 255, so you could add (255/15) 17 channels of 4 bits without clipping. Five bits gives values of 0 to 31, and therefore you can only add (255/31) 8 channels of 5 bits without clipping. It's true that most of the time, the samples w...
by tomaitheous
Sat Feb 16, 2008 8:20 am
Forum: Sound
Topic: MOD/S3M player for the MD
Replies: 31
Views: 20333

The DAC on the ym2612 is 8 bits. If you add channels so that they don't clip, that reduces the resolution by log2(# channels added together). As you mentioned, S3M uses 16 digital channels, so that means each channel can only be 4 bits to avoid saturation when you add then together." Oh, but I wasn...
by tomaitheous
Sat Feb 16, 2008 2:47 am
Forum: Sound
Topic: MOD/S3M player for the MD
Replies: 31
Views: 20333

It would be great option to waste all MD resources to get very crappy digital sound. How do you figure? 15khz 8bit MOD player is hardly crappy digital sound. FM is limiting in that in it's repetitive use of the same sounds/instruments gets "old". It's great if you *want* that classic sound, and not...
by tomaitheous
Sat Feb 16, 2008 12:00 am
Forum: Sound
Topic: MOD/S3M player for the MD
Replies: 31
Views: 20333

MOD/S3M player for the MD

I'm in the process if writing a mod player for another console and was wondering if anyone has written one for the MD? I was think about how you'd go about writing the main PCM driver that all the channels would be mixed into. Can you generate an HINT for every scanline or are you just limited to ac...
by tomaitheous
Wed Jan 09, 2008 9:37 am
Forum: Tools
Topic: Tile Extractor 2.5 from retrospec
Replies: 6
Views: 6693

...or perhaps I didn't find a easier way ? how do YOU do that ? I use "Create map from big picture". I create a new project with tile dimensions of 8x8, leave the map setting at 100x100 or make it larger if needed, but the exact size isn't important as long as it's the same size or larger. Then I u...
by tomaitheous
Tue Jan 08, 2008 10:54 pm
Forum: Tools
Topic: Tile Extractor 2.5 from retrospec
Replies: 6
Views: 6693

Mappy does that as well. You can build map from an whole image, remove duplicate tiles, then export just the tiles in what ever row/column setup you want. Tile Extractor gives you offset options, though.
by tomaitheous
Sun Dec 30, 2007 9:32 pm
Forum: Demos
Topic: My first demo: a 64 color image
Replies: 21
Views: 14409

Sorry for the late reply :( In fact I'm not sure I see what you mean; but if I did, with this you can have 16 colors per 16 pixels, but you still aren't free to select them; in fact every tile's first and second row use the first palette. Yes, every group of 16 pixels will have access to any 16 col...
by tomaitheous
Sat Dec 29, 2007 1:40 am
Forum: Demos
Topic: My first demo: a 64 color image
Replies: 21
Views: 14409

I'm not sure I understood your explanation, but my lack of knowledge about the MD hardware combined with my rather bad english is probably the reason Wink For the 8x2 tile method? Okay, it goes like this: In a normal 8x8 tile, any one of those 64 pixels can access one of 16 colors from a single pal...
by tomaitheous
Fri Dec 28, 2007 11:48 pm
Forum: Blabla
Topic: Combinatorial/Sequential divider?
Replies: 2
Views: 3617

Re: Combinatorial/Sequential divider?

Besides the subtracting/comparing n.times and the count/multiplying/comparing is there any method to do A/B for any given A and B? [] :wink: An example of binary division. 1100 remainder 1 ------ 101/111101 -101 ------ 10101 -101 ------- 01 Taken from the WDC progamming manual: There are several me...
by tomaitheous
Fri Dec 28, 2007 10:48 pm
Forum: Demos
Topic: My first demo: a 64 color image
Replies: 21
Views: 14409

Brunni, are you using a single BG plane and just 4 palettes for you image conversion? Or are you using two BG layers and one sprite layer? Anyway, if you're going to alternate between to colors it might be a better idea to not use solid colors/areas. If you alternate between to dithered patterns, th...
by tomaitheous
Sat Dec 01, 2007 9:21 pm
Forum: Megadrive/Genesis
Topic: Genesis Address Bus and Max RAM
Replies: 35
Views: 25177

I'll try to dig up those docs and scan them. They were really useful at the time when I got them (sent in a request for info and samples on company stationary). There was one REALLY odd processor they had in particular - it was two 65C02's in a single package. Quite a bit of the timing was the same...
by tomaitheous
Fri Nov 30, 2007 12:39 am
Forum: Megadrive/Genesis
Topic: Genesis Address Bus and Max RAM
Replies: 35
Views: 25177

I have the technical documentation on the R65C02, and it is INDEED microcoded. Rockwell brags about how microcoding allowed them to easily add the extra opcodes, but did alter some of the instruction timings. That's the first that I've heard of that. And the opcode timings are very close to the WDC...
by tomaitheous
Thu Nov 29, 2007 9:29 pm
Forum: Megadrive/Genesis
Topic: Genesis Address Bus and Max RAM
Replies: 35
Views: 25177

The MOS version of the 6502 was not microcoded, either was the CMOS version (65C02). I don't think any of the license cores were microcoded back then either (GTE65CS02, 65CE02, HuC6280) as they have the same opcode timings. That's one of the reasons why the 65xx series are so fast in comparison to t...