exxos's Atari, Amiga & retro forum

Congrats on getting the A2 running Anders!

Over the weekend, via the EmuTOS mailing list I learned of another very cool open source M68K machine, Y Ddraig (Welsh for The Dragon).

Its not as powerful as the Raven but I think it would be cool to see some sort or co-operation between the two platforms if and where possible. 68060's are not cheap so that alone might price the Raven out for some. The Dragon should be a bit more affordable.

Sorry if this has already been mentioned here.

https://ddraig68k.com/

danboid wrote: 13 Jul 2026 08:12 Congrats on getting the A2 running Anders!

Over the weekend, via the EmuTOS mailing list I learned of another very cool open source M68K machine, Y Ddraig (Welsh for The Dragon).

Thank you!
The portability of EmuTOS is really good indeed, and I think a great OS choice for any m68k based machine :)

Have been hunting an ADC issue off and on and finally.. solved! :)
The sampled data was so catastrophically bad that my head was completely locked into thinking it _had_ to be my DSP code and me misunderstanding how to configure ESSI correctly for the i2s data stream.

But in the end, turns out I was missing series capacitor on the audio input to the ADC.
So.. traces cut, capacitors soldered in, and I finally have clean audio coming into the DSP from the ADC :)

Schematics, gerbers and so on which lives on Github has been updated with this fix.

And the external 128 kword SRAM for the DSP has now also been tested and verified working.
With DSP clocked at 90mhz it can do 1 waitstate access to 12ns SRAM so the bootup dsp code configures it for that timing.

agranlund wrote: 14 Jul 2026 21:44 And the external 128 kword SRAM for the DSP has now also been tested and verified working.
With DSP clocked at 90mhz it can do 1 waitstate access to 12ns SRAM so the bootup dsp code configures it for that timing.

Nice! You'll be making @dml mouth water :P

Scrappy bird has fancy toys too now :)


YM2149 -> ADC -> DSP56303 -> DAC -> Lineout
Running an example DSP56001 reverb effect ported to DSP56303.

Awesome! You made chip music slightly less annoying! :lol: :thumbup:

\o/

I guess (obviously) that means you got it all working :)


:dualthumbup:

:cheer: :cheer: :cheer: I'm gonna have to build a second one now :lol:

Well done @agranlund sounds awesome.

Smiles and thumbs up from me too.

The reverb effect is ported from the Falcon DSP. Is it a case of playing back SND Player through an existing DSP realtime effects player, or is there more to it?

I'm thinking of either CT60 or stock Falcon to try this on.

agranlund wrote: 19 Jul 2026 12:38 YM2149 -> ADC -> DSP56303 -> DAC -> Lineout
Running an example DSP56001 reverb effect ported to DSP56303.

great,
what was changed in DSP56001 asm in to run on DSP56303?