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barnieg

[AQUARIUS] AY-8914? programming

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I'm trying to get my head around the compatibility of the Aquarius mini-expander soundchip, It's seems that it is the less common AY-8914 is this correct? If so how does this effect porting sound from another Z80 based system that might use an AY-8910 or AY-8912 are they functionally identical in regards to programming?

 

Finally is it exact same chip in the Intellivision?

 

 

Barnie

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The AY-3-8914 was the sound chip used in the Intellivision. I don't have any Intellivision docs handy, but for whatever it's worth, here's something from Wikipedia: "The AY-3-8914 has the same pinout and is in the same 40-pin package as the AY-3-8910, except the control registers on the chip are shuffled around, and the 'expected input' on the A9 pin may be different. Otherwise it is exactly the same as the AY-3-8910. It was used on the Mattel Intellivision."

 

The Aquarius Mini Expander uses an 8910:

 

miniexpander.jpg

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The greatest differenced (pinpoint by intvnut) is that the volume for activating the envelope register is 48 decimal instead of 16 as commonly used for AY-3-8910.

 

Not sure about the I/O bits for Aquarius, but in Intellivision the wrong bits for mixer register turns off the second controller.

 

Otherwise both are the same.

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The greatest differenced (pinpoint by intvnut) is that the volume for activating the envelope register is 48 decimal instead of 16 as commonly used for AY-3-8910.

This is mentioned in the "Your friend the EXEC" PDF document in the "VOLUME CONTROL" section (page 103 of 119).

 

Not sure about the I/O bits for Aquarius, but in Intellivision the wrong bits for mixer register turns off the second controller.

On the Inty bits 6 and 7 in the mixer register determine if the I/O ports used to interface to the controllers are inputs or outputs.

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I'm trying to get my head around the compatibility of the Aquarius mini-expander soundchip, It's seems that it is the less common AY-8914 is this correct? If so how does this effect porting sound from another Z80 based system that might use an AY-8910 or AY-8912 are they functionally identical in regards to programming?

 

Finally is it exact same chip in the Intellivision?

 

 

Barnie

Here are some documents which say the Aquarius uses the AY-8910 and how it is incorporated within the Mini Expander.

Aquarius AY-3-8910.pdf

post-29961-0-06610000-1435262084_thumb.jpg

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Looking at that schematic its the same situation as the Inty. If you get the direction bits wrong in the mixer register you'll stop the controllers from working.

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Looking at that schematic its the same situation as the Inty. If you get the direction bits wrong in the mixer register you'll stop the controllers from working.

Yes. That also explains why the 8910 can't be used as a drop-in replacement for the 8914, even though the pinout is supposedly the same. I seem to remember trying it with one of my Intellivisions in the days before I knew better, and unsurprisingly, I didn't get any response from the hand controllers.

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Another question pops up discussing the AY-8910. Has anybody ever tried to use any of the ZX Spectrum, MSX etc. special tools to rip the AY-8910 based music from their programs, or use the already ripped music and convert these to the Aquarius?

 

Here are some webpages, just to give you some idea how many of these exist, and it would be great if we could use one of these for the Aquarius, without reinventing it especially for the Aquarius.

http://www.worldofspectrum.org/utilities.html

http://bulba.untergrund.net/main_e.htm

 

It would be great to have something like these tunes inside any home-brew game

 

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Several of the Spectrum/Amstrad trackers come with the source code to play back the tunes in Z80 machine code. Converting one shouldn't take very much time for somebody that knows the Aquarius well. As far as I can tell they don't use file I/O or anything particularly machine specific and basically just work off a pointer to the tune.

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Several of the Spectrum/Amstrad trackers come with the source code to play back the tunes in Z80 machine code. Converting one shouldn't take very much time for somebody that knows the Aquarius well. As far as I can tell they don't use file I/O or anything particularly machine specific and basically just work off a pointer to the tune.

Someone who know the Aquarius well you say...... I can send you some documentation on the Aquarius too you know :grin:.

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Someone who know the Aquarius well you say...... I can send you some documentation on the Aquarius too you know :grin:.

:lol: True! But I haven't done Z80 for a very, very long time. Perhaps if I ever get an Aquarius (at a reasonable price on ebay) I might have a go.

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:lol: True! But I haven't done Z80 for a very, very long time. Perhaps if I ever get an Aquarius (at a reasonable price on ebay) I might have a go.

A there is hope ;-) ! Barnieg finally managed to get hold of a reasonably priced UK Aquarius, so maybe the next one lucky enough will be you ;)

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A bankswitched cartridge can provide LOTS of room for nice music, so I definitely plan to do something with one of those AY trackers, once I have some development tools which will make testing easier. For now, I've got to get back to work on those ...

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A there is hope ;-) ! Barnieg finally managed to get hold of a reasonably priced UK Aquarius, so maybe the next one lucky enough will be you ;)

I have checked ebay.co.uk far more frequently for Aquarius machines since Barnieg mentioned he'd snagged one for a good price. To be honest, there are other machines that I'd quite like to tinker with before the Aquarius.

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I picked up one of the "new old stock" Amstrad GX 4000's recently - there are a few left...

 

I'm going to stick to Z80 based machines with AY sound chips for the time being :-)

 

I have checked ebay.co.uk far more frequently for Aquarius machines since Barnieg mentioned he'd snagged one for a good price. To be honest, there are other machines that I'd quite like to tinker with before the Aquarius.

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I picked up one of the "new old stock" Amstrad GX 4000's recently - there are a few left...

I have a few of those myself. I'm tempted to pick up the new multi-cart that came out for it recently.

 

I'm going to stick to Z80 based machines with AY sound chips for the time being :-)

:cool:

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I have checked ebay.co.uk far more frequently for Aquarius machines since Barnieg mentioned he'd snagged one for a good price. To be honest, there are other machines that I'd quite like to tinker with before the Aquarius.

Of course there is a choice in so many systems to pick from and the Aquarius is not the most obvious one. That said if you are an Inty fan, some love must also exist for the humble Aquarius ;-) !

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I have a few of those myself. I'm tempted to pick up the new multi-cart that came out for it recently.

 

 

:cool:

Here is a thought: why not just wait for the Aquarius Superfont from Jay to be available, refresh your memory a bit on the Z80 and develop a cross selling game for several similar Z80 machines including the Aquarius? :grin:

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Its a nice idea but the Aquarius does have quite a few limitations compared to other machines of the time. Making a game that takes advantage of what it offers is probably a much better approach. Something like LumASCII from the Speccy would be good :-

 

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Its a nice idea but the Aquarius does have quite a few limitations compared to other machines of the time. Making a game that takes advantage of what it offers is probably a much better approach. Something like LumASCII from the Speccy would be good :-

 

Of course you are right, but an Aquarius with Mini Expander and Superfont upgrade would probably match a ZX-Spectrum, which games are ported to the Amstrad CPC a lot of times. Also an MSX1 and Colecovision version would not be very different. Only if you want to make use of the hardware sprites of those two, it would take some re-coding.

Edited by Aquaman

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Of course you are right, but an Aquarius with Mini Expander and Superfont upgrade would probably match a ZX-Spectrum, which games are ported to the Amstrad CPC a lot of times. Also an MSX1 and Colecovision version would not be very different. Only if you want to make use of the hardware sprites of those two, it would take some re-coding.

The problem with internal mods is not everybody has them installed. So if you write software for them, the percentage take-up of your game is a niche of a niche. If it plugs in the cart slot then its worth doing a game that targets the advanced hardware. I think the Aquarius needs an SD drive of some kind. That would make it much more fun to use as a system and to develop new homebrews for.

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The problem with internal mods is not everybody has them installed. So if you write software for them, the percentage take-up of your game is a niche of a niche. If it plugs in the cart slot then its worth doing a game that targets the advanced hardware. I think the Aquarius needs an SD drive of some kind. That would make it much more fun to use as a system and to develop new homebrews for.

If the games are good enough, I think most serious Aquarius users will eventually feel the need to upgrade with Superfont, to be able to enjoy these. :) But I can see your point and that's why I thought of the multi-system approach. As for an SD drive or something like that, Jay and I think even Martin are working on a solution to get some kind of speedy mass storage available for the Aquarius. This would make the Aquarius a more serious homebrew system.

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