Search found 110 matches

by metalages
Tue Jun 19, 2018 8:01 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

new commit : https://github.com/gibs75/demOS BLSplay 1.4.0 - add support for delay sample effect (0xEDx) - on PC : closing the window closes the player - little optimizations in ASM - split ASM source (inits / play) - update unit tests - update doc BLSconvert 1.1.0 - add support for delay sample eff...
by metalages
Thu Jun 14, 2018 6:12 am
Forum: CosmosEx
Topic: CosmosEx - new device for your Atari ST
Replies: 542
Views: 159291

Re: CosmosEx - new device for your Atari ST

... I'd be very, very, very, very interested in such an extension! I pondered the possibility in this thread: http://atari-forum.com/viewtopic.php?f=15&t=33207&p=339572#p339572 The way I imagined it would be to tap into the VDI calls, and send the drawing instructions (not bitmap data) over...
by metalages
Thu Jun 07, 2018 7:39 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

BLSplay v1.2.0 submitted => speed up init samples process (was really slow)
by metalages
Tue Jun 05, 2018 8:32 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

New release of BLSplay and BLSconvert with support of STe balance (microwire) like described into doc

https://github.com/gibs75/demOS
by metalages
Sun Jun 03, 2018 7:06 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Code and binaries are on github :)

So it is available for musicians and coders (ask me if you need help)

I think at some point I will find time to make a musik disk if some musicians are interested to collaborate but I am currently quite busy :(
by metalages
Sat Jun 02, 2018 9:34 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

... and sources + binary released here

https://github.com/gibs75/demOS
by metalages
Sat Jun 02, 2018 9:15 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

I have tested on STe. Here is the result : https://youtu.be/ehSvjL8RLo4 It works the same way than in Hatari => nearly no click, but I have the feeling that even with DMA in loop mode, I have some clicks when running at display time instead of start of VBL (not really a problem as I do not see the p...
by metalages
Sat May 26, 2018 9:31 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Ok it now works in C and ASM perfectly on Hatari :)
Need to check on real hardware now...
by metalages
Sat May 26, 2018 8:17 pm
Forum: Games - General
Topic: Escape 2042 - A new game for Atari STe
Replies: 31
Views: 2092

Re: Escape 2042 - A new game for Atari STe

It looks really cool. Nice work.
by metalages
Tue May 22, 2018 9:26 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Ok. In order to avoid these problems I went for something like you have proposed in a first time Nicolas : - DMA in loop mode - 3 buffers - chain assignments of dma start / end adresses on buffers (1, 2, 3, 1, 2, 3...) at a point later where I am sure new adresses have been acquired by dma - monitor...
by metalages
Mon May 21, 2018 6:13 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Ok I have something working with de-sync looping-dma and replay routine using 4 buffers. So no more click indeed. Drawbacks with this approach are : - there is a small desync in replay / rythm when I catch up. Can be accpetable as it does not happen so often. - it would be difficult with this approa...
by metalages
Mon May 21, 2018 9:03 am
Forum: Ym rockin'
Topic: Turbochip - 7-channel YM+DMA replay
Replies: 18
Views: 1843

Re: Turbochip - 7-channel YM+DMA replay

Before going on this prototype http://cyber.savina.net/sound/sound.htm I have tried to figure out how to work in a cheap way with wave table. I had the feeling would be possible to have something rather cheap on 2 channels : 1 for wavetable, 1 for drum - use looping DMA buffer set with the length of...
by metalages
Thu May 17, 2018 2:38 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Does this mean something around 50.23 VBL per sec => 996.73 DMA sound samples per sec ?
by metalages
Thu May 17, 2018 9:36 am
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Excellent. Things get really more clear about how STe operates with your explanations :) (also get things more clear in my mind ;)) I think I will try something like : - triple buffer with constant DMA looping on the 3 buffers - monitor the current play address to decide where to generate (or not) t...
by metalages
Wed May 16, 2018 8:58 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

I can try this way, but my problem in this case is : if I do not always generate 1000 samples (per channel) per frame, I am not sure everything will divide so well in different cases... Maybe another way is to use a triple buffer and have only one constant DMA looping on these three buffers. Then co...
by metalages
Tue May 15, 2018 9:05 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Whaou a lot of valuable quality info in there, tx :) About quality of pre-transpose + blitter mixing, there is a way to check : if you run BLSplay in test mode (add -test to command line),it will dump the generated sample into a file instead of playing with DMA sound. This file will be generated int...
by metalages
Mon May 14, 2018 9:10 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Thank you for your tests and detailled answer :) I have tried to figure out where the clicks can come from. I have the feeling that some appear when the sample is retriggered at each new note (sample is retriggered without any smoothing). On Facebook, Troed has also talked about usual clicks on STe ...
by metalages
Sun May 13, 2018 6:33 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Sorry I did not find the time to test on my STe. On the current version of BLSplay, you can toggle voices on / off with keys 5 to 8 (not the numpad) Clicks were very clear in Hatari on bassline (voice 1). QUICKIE.BLS and _QUICKIE.BLS are the same module but two voices have been inverted on _QUICKIE....
by metalages
Fri May 11, 2018 11:52 am
Forum: STOS
Topic: Hardwarescrolling Control3.5a extension
Replies: 49
Views: 4394

Re: Hardwarescrolling Control3.5a extension

Basically you have a score interpreted at some point that tells the render part executed each frame what to do with the samples. The concept is not complicated but .MOD manages a lot of different effects that apply on the rendering. Managing all effects cases correctly needs work in my opinion. Wizz...
by metalages
Thu May 10, 2018 9:01 pm
Forum: STOS
Topic: Hardwarescrolling Control3.5a extension
Replies: 49
Views: 4394

Re: Hardwarescrolling Control3.5a extension

I think it is easier to use wizzcat Ste protrack routine in this case, set it at 12.5khz and modify the mixing routine which is quite simple to get mono directly instead of stereo. Probably more efficient and lot simpler than Lance routine for that. Also as Lance routine uses microwire would be mor...
by metalages
Thu May 10, 2018 4:53 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

QUICKIE.BLS and _QUICKIE.BLS uploaded on git...
by metalages
Thu May 10, 2018 4:49 pm
Forum: Coding
Topic: Blitter sound routine
Replies: 64
Views: 12492

Re: Using blitter for sound mixing

Yep indeed. I have inverted the condition to have the display synched by default when running without renaming the variable. My fault :$ Clicks happen when starting on line 63. I have to try on real STe but not tested yet as it is in a cupboard. BLSPLAY.TTP is available at the root. I have tested wi...
by metalages
Wed May 09, 2018 8:47 pm
Forum: STOS
Topic: Hardwarescrolling Control3.5a extension
Replies: 49
Views: 4394

Re: Hardwarescrolling Control3.5a extension

(if I well remember playing at 12.5khz with Wizzcat routine should be around 25% CPU)
by metalages
Wed May 09, 2018 8:33 pm
Forum: STOS
Topic: Hardwarescrolling Control3.5a extension
Replies: 49
Views: 4394

Re: Hardwarescrolling Control3.5a extension

I think it is easier to use wizzcat Ste protrack routine in this case, set it at 12.5khz and modify the mixing routine which is quite simple to get mono directly instead of stereo. Probably more efficient and lot simpler than Lance routine for that. Also as Lance routine uses microwire would be more...

Go to advanced search