Amiga 16-bit AHI audio support (Update: Released!)

[limi]

Now that we have RTG support available in MiSTer, the next missing piece of the classic “upgraded” Amiga in addition to the ability to use graphics cards would be… sound card support.

For those of you who don’t know, Amiga had support for 16-bit audio interfaces like Delfina, Prelude, Toccata, etc. It was the “retargetable audio” interface for the Amiga, where the hardware was abstracted away, and allowed AmigaOS to address a set of Amiga sound cards. It was later included in official AmigaOS releases.

The FPGAArcade Replay board seems to supports it.

Does anyone know how complicated it would be to support this with an Amiga AHI driver to address the DE-10 Nano audio output?

Developer package can be found here.

[limi]

I guess it’s time to bump this; would this be hard to port the FPGAArcade approach to MiSTer’s audio output to get 16-bit audio from the Amiga core? It’s one of the things I miss from my original Amiga 4000 setup:

https://github.com/FPGAArcade/amiga_cod ... ter/xaudio

[LamerDeluxe]

I have a Delfina card in my 4000 as well, support for AHI would be great. Even without optional audio hardware, AHI was able to proved 14-bit audio with the on-board Amiga audio chip (Paula).

[bazza_12]

woah I wasn't even aware the amiga supported additional sound cards.. that's mind blowing in itself..

[Ranzbak]

Hi,

I am working on my own Minimig project, and implemented a partial Toccata sound card in SystemVerilog.
The card only does playback of audio, since recording doesn't make much sense in my project.
Given that it works in my Minimig project, it might be of interest for the Mister project as well.

https://github.com/ranzbak/fpga-toccata

I don't own a Mister myself, so I can't verify if the code works without modification on an Intel FPGA, changes should be trivial though.

[hitm4n]

Hi,

I am working on my own Minimig project, and implemented a partial Toccata sound card in SystemVerilog.
The card only does playback of audio, since recording doesn't make much sense in my project.
Given that it works in my Minimig project, it might be of interest for the Mister project as well.

https://github.com/ranzbak/fpga-toccata

I don't own a Mister myself, so I can't verify if the code works without modification on an Intel FPGA, changes should be trivial though.

Thanks for sharing. Its way beyond me, but hopefuly someone might pick this up, port it over and implement it in MiSTer

[limi]

This is fantastic! Thank you so much for embarking on this, the last “missing piece” of the late-stage Amiga owner setup (Amiga 4000 + RTG + AHI)

Hopefully we can get it added to MiSTer.

EDIT: Filed a ticket: https://github.com/MiSTer-devel/Minimig ... issues/171

[kolla]

Hohum - no MiSTer just has to have it too!

https://www.atari-forum.com/viewtopic.p ... e7#p458089

[Higgy]

You beat me @kolla , I was going to say thanks to @Ranzbak as this has now been added to the MiST MiniMig Core.

[Ranzbak]

Thank you all as well, it feels good to see the module in other projects as well

[robinsonb5]

I'm making some progress porting this to MiSTer. @Ranzbak, I have some more testing to do, but I'll PM you here in the near future with some queries, if that's OK, since I remember we had some difficulty with spam filters swallowing our emails!

[limi]

Fantastic! I’m also happy to help test, especially since I am familiar with AHI/Toccata from owning an Amiga with it back in the day, and also because I want to add AHI support to AmigaVision. Just send me a direct message here (or on Twitter) if you want more testers.

[robinsonb5]

Fantastic! I’m also happy to help test, especially since I am familiar with AHI/Toccata from owning an Amiga with it back in the day, and also because I want to add AHI support to AmigaVision. Just send me a direct message here (or on Twitter) if you want more testers.

That's great - I've just attached a test RBF to the issue you opened on github. I don't have any real experience of Toccata or AHI, so I've just been testing with OctaMED Soundstudio so far.

On MiST there's an odd interaction between this and RTG screens - operations like opening windows and flipping screens cause the audio to stop dead - but it doesn't happen when using AGA modes. I don't have RTG set up on MiSTer yet, so it'd be useful to know if the same thing happens there.

[CartoonDonkey]

It would be very cool to see 68060 cpu implementation in this core. Processing of 16 bit audio would be really helped by it, among other things.

[Armakuni]

It would be very cool to see 68060 cpu implementation in this core. Processing of 16 bit audio would be really helped by it, among other things.

The core is limited by the TG68K 020 module but is the only open source option available.

[limi]

This has now been merged into the Minimig core; AmigaVision support will follow.

[NightShadowPT]

This sounds great (pun intended)

I have never come across an Amiga with an additional sound card. What is the use case here?

Are there any games that support this? (that also run on the MiSTer?)

[LamerDeluxe]

This sounds great (pun intended)

I have never come across an Amiga with an additional sound card. What is the use case here?

Are there any games that support this? (that also run on the MiSTer?)

My Amiga 4000 has a Delfina sound card (I've had it since the late nineties). Using the AHI system, it can be used for a number of applications, as well as some games. I remember using it with Genetic Species (excellent game BTW) and it worked really well.

[limi]

It’s not that useful for games, but pretty great for e.g. playing back 16-bit S3M tracker music.

I’ve been putting it off a bit for AmigaVision since the use case is very marginal (but cool!)

PS: I had a Delfina in my A4000 as well! Great sound card.