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3DO chip sound?

Posted: Fri Jul 29, 2011 8:41 am
by Jones
Is the 3DO capable to do chip generated music?

If I got the data sheet right, it's only sound dedicated
chip is the custom made CISC DSP chip, which is "only"
able to manipulate and decompress sampled sound data.

So, no synthesizer, no midi, no wavetable but only
audiotracks and sampled audio data for music?

Posted: Sat Jul 30, 2011 5:45 am
by Nikk3do
Jones, the 3DO DSP has all ability to process audio. In 3DO SDK, there is a part of docs and samples which explains how working with MIDI sequences. And even more, DSP can be used for fastest user data processing. This is a very flexible device.

Posted: Mon Aug 01, 2011 10:15 am
by Jones
This is very interesting, thanks for the info! :)

This makes me remember a discussion long time ago on
the FreeDO forum.
It was about MP3 decoding on the 3DO - someone said that
with the use of that DSP, the 3DO could theoretically be able
to decode MP3s in realtime.
(Though it would require "the hell of mathematics" to do
the coding for a player like that)

This was very interesting news as well, since the Playstation 1
actually was not capable of doing this. So in some things, the
3DO has had more processing power than the PS1.

Posted: Mon Aug 01, 2011 2:57 pm
by acem77
I thought it had midi, play a game like super wing commander.
sounds like midi to me.

Posted: Mon Aug 01, 2011 10:20 pm
by Jones
Nikk3do wrote:And even more, DSP can be used for fastest user data processing. This is a very flexible device.
Wait a minute...
That means, as long as a program doesn't use any sound, this chip
could also be used for polygon processing, increasing the graphic
frame rate?

Posted: Tue Aug 02, 2011 4:22 am
by Nikk3do
I think the some image postprocessing or graphics FX can be realised on DSP. MP3 processing is problematic, becouse decoding process need a lot of floating point math operations wich not presents in 3DO hardware (only 32 bit fixed point). But many audio processing algorithmes can be realised pretty well (for example ADPCM decoding).

Posted: Tue Aug 02, 2011 8:12 pm
by Jones
This is fantastic! :)

So the 3DO has actually 3 processors to possibly do 3D calculations:

- 12,5MHz ARM60 (32bit)
- 12,5MHz NTG maths-copro (32bit)
- 25MHz DSP (16bit).

(plus, finally, the 2 CEL engines for the end-rendering and effects)

The Arm CPU outputs (as far as I know) 10 MIPS of power.
Do you have any information how fast the DSP is?

Posted: Wed Aug 03, 2011 6:02 am
by Nikk3do
Jones wrote:Do you have any information how fast the DSP is?
Unfortunately, I did not have much information on the 3DO architecture. Some information from SDK, some from 3DO patents, some from my own architecture study. I think the DSP core is faster then ARM on operations with short data types and I know that the DSP 25 MHz clock frequency is more than ARM 12,5MHz. :)) Probably later I will have more informations on DSP. I just started to study.