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foft

Pokeymax v2

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Hi foft,

 

For v1 there was a topic , and there was a chance to make a mono core (1 pokey) having each of the 4 channels with a separate physical output. Such design/layout will allow to have stereo/quad output for the 99.9% of the current software available, which is mono (1 pokey).

 

I'm not sure why there is interest in quad pokeys (or even octa, penta, ... tera), besides the theoretical interest of course, because it's targeting only the 0.001% of available software, and has not arisen yet a huge interest in having a 4 channels output, that will work with the current 99.9% of software.

 

If the PCB can output such configuration (with a clean sound for each of the 4 channels), and if it's possible to do such firmware, I would be interested in at least 1.

 

 

post-64419-0-82061500-1559583401.png

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Well there are still 4 audio outputs:

pin 37 + 3 on audio header.

Its possible to route the audio output to them however desired without too much effort.

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57 minutes ago, tane said:

Hi foft,

 

For v1 there was a topic , and there was a chance to make a mono core (1 pokey) having each of the 4 channels with a separate physical output. Such design/layout will allow to have stereo/quad output for the 99.9% of the current software available, which is mono (1 pokey).

 

I'm not sure why there is interest in quad pokeys (or even octa, penta, ... tera), besides the theoretical interest of course, because it's targeting only the 0.001% of available software, and has not arisen yet a huge interest in having a 4 channels output, that will work with the current 99.9% of software.

 

If the PCB can output such configuration (with a clean sound for each of the 4 channels), and if it's possible to do such firmware, I would be interested in at least 1.

 

 

post-64419-0-82061500-1559583401.png

I'm curious as to how 4-channels would actually be used. Most people have amplified stereo speaker set-ups, like what you would buy for connection to a PC. So would the 4 channels be mixed down into 2 channels, with 8 voices per channel?

 

Edit: I just looked at your diagram and that appears to be what is proposed.

 

 

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Did someone say SID? 

 

My ears perked up immediately!  Would this just a matter of switching cores -- as with MIST? Not in the original scope, but what is possible with the SID?  Just a thought -- would a SID be possible with EclaireXL?  Of course, having one POKEY would be necessary for compatibility.  2 POKEY and One SID sounds very cool.  Dare I even think it -- 2 SID and 1 POKEY? 

 

And if this is all covered in the original thread, I apologize, but I never read it, except your reference here.

 

-Larry

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1 minute ago, Larry said:

Did someone say SID? 

 

My ears perked up immediately!  Would this just a matter of switching cores -- as with MIST? Not in the original scope, but what is possible with the SID?  Just a thought -- would a SID be possible with EclaireXL?  Of course, having one POKEY would be necessary for compatibility.  2 POKEY and One SID sounds very cool.  Dare I even think it -- 2 SID and 1 POKEY? 

Yes why not 🙂

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38 minutes ago, mytek said:

I'm curious as to how 4-channels would actually be used. Most people have amplified stereo speaker set-ups, like what you would buy for connection to a PC. So would the 4 channels be mixed down into 2 channels, with 8 voices per channel?

 

Edit: I just looked at your diagram and that appears to be what is proposed. 

 

For my example here is an a music file produced by VinsCool, showing the output of what it seems to be the output of the 4 channels.

 

Hypothesis: we have a standard mono Atari, and the music file tested is also mono, and the Pokeymax can split all 4 channels.

 

With a standard Atari, there is a mono output, both left and right the same. Now imagine with Pokeymax to have an stereo output, starting from a mono software (1 pokey). So, some of the 4 channels can be directed to the left speaker (for example 2, like previous diagram), and the rest to the right speaker, generating a new stereo sound starting from a mono sound (2 channels to the right, and 2 to the left). It's also possible to build other configuration with switchs according to tastes of each one. That will be really interesting, the fact of generating an stereo or quad sound from a mono software.

 

 

 

Edited by tane
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Hello Tane

 

If you'd split up the output of each channel into four signals, most existing mono sound files would sound like the early stereo records.  Paul on one speaker, John on an other, George on number three and Ringo on speaker number four.  (Just an exaggerated example to make a point, most albums only had stereo)

 

Sincerely

 

Mathy

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Audio sound on the left channel, tape data on the right channel.

Errrm, music on the left channel, vocals on the right channel.

 

Alas, we don't have many Pokey sounds with vocals, so it should be some Pokey sound channels on the left speaker and the other Pokey sound channels on the right speaker. That's how it was done with some older mono Pokey sound, when it was converted into stereo...

 

In Mega Magazine nr. 3 Frankenstein (today F#Ready?) gave tips how to patch some mono software for stereo, but with Pokeymax it should be possible to leave the old A8 software as is (unchanged) and just write firmware for Pokeymax that routes e.g. Pokey channels 1 and 2 to the left speaker and channels 3 and 4 to the right speaker. Think something similar is done when RMT plays four Pokey channels in stereo...

 

-----

 

Excerpt from Mega Magazine 3:

 

" If the program doesn't use filters, you can simply throw channel one and two on the old pokey and channel three and four on the new (second) pokey. If it uses a filter into channel two, clocked by channel four, you got a problem, since you've just shared those channels with the new pokey! Fortunately this filter is not used in all music programs.
          
With this idea in mind I began to write a short program to update the best music program for the Atari 8-bit computer: SoftSynth! The program needs an original SoftSynth program disk and it will update all three music play files. Because I only change the $D205 to $D215 and $D217 to $D217, the program won't act differently if you use an ordinary 'single pokey' computer (on a normal system $D210-$D2FF are duplications of locations $D200-$D20F).
          
This way it's also easy to modify the so called ZUPKGC musix. Examples of ZUPKGC music are: draconus, zybex, panther, bmx simulator etc. (all musix from the BIG demo music menu and probably a few more). The programmer who made the play routine for these musix has been very friendly to us, because he only 'pokes' the sound channels at one point in the program. Several demo coders have taken advantage of this, by directing these 'pokes' to an equalizer graphic or something like that. So, why not direct two channels to the new pokey!?
         

Okay, I'll give you some tips about how to change such music files:
First search for a piece of program which looks like this:
          
                    LDX #8
          LOOP      LDA $xxxx,X
                    STA $D200,X
                    DEX
                    BPL LOOP
          
Here the sound channels are 'poked'. Notice that $xxxx can be anything! It depends on where in memory the music player is located. We replace this routine by:
          
                    JSR NEWROUT
                    NOP
                    NOP
                    NOP
                    NOP
                    NOP
                    NOP
                    NOP
                    NOP
          
NEWROUT is our own routine to 'poke' both pokey chips. Without loops and things it would be like this:
          
          NEWROUT   LDA $xxxx
                    STA AUDF1     ; $D200
                    LDA $xxxx + 1
                    STA AUDC1     ; $D201
                    LDA $xxxx + 2
                    STA AUDF2     ; $D202
                    LDA $xxxx + 3
                    STA AUDC2     ; $D203
                    LDA $xxxx + 4
                    STA AUDF7     ; $D214
                    LDA $xxxx + 5
                    STA AUDC7     ; $D215
                    LDA $xxxx + 6
                    STA AUDF8     ; $D216
                    LDA $xxxx + 7
                    STA AUDC8     ; $D217
                    LDA $xxxx + 8
                    STA AUDCT1    ; $D208
                    STA AUDCT2    ; $D218
                    RTS
         

Notice that we poke the AUDCT of BOTH pokeys (AUDCT1 and AUDCT2). As far as I know the ZUPKGC musix doesn't use filters, but does link two channels to act like one 16-bit channel (Thanx Yeb for this info). So, it can happen that you hear two channels through the left speaker, and only one channel (16-bit) through the right speaker.
          
One thing must not be forgotten. The pokeys have to be initialized before you start the music (VBI). Normally the old pokey is already initialized by the OS, but after each I/O operation it needs to be re-initialized. Just insert something like this:
          
          INIT      LDA #3
                    STA SKCTL1    ; $D20F
                    STA SKCTL2    ; $D21F
                    RTS
          
Well, that it! I hope this will help you to update any program you like. Please let me know which ones you updated so maybe we can publish more update progs in the future. How about arcade games in stereo!? Maybe more about this in the next issue.. Have fun!
          
PS: On side two you'll also find the Turbo Basic program 'WONDERS.TUR'. This is made to update the 'World of Wonders' demo containing music made with the SoftSynth program. "

 

Edited by CharlieChaplin

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It would suit me just fine if (2) cores were on each side, Right and Left. That gives 8 voices per side.

If there is space to add a couple of Sound Inferior Devices(SID)s, then put one on Right and the other on Left.

 

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On 8/30/2019 at 5:16 PM, Mathy said:

If you'd split up the output of each channel into four signals, most existing mono sound files would sound like the early stereo records.

That's right. But you can make combinations, for example CH1 and CH2 to both speakers left and right, plus CH3 to only left and CH4 to only right, according to what is used most frequently for each channel. For games I would choose background music to both speakers and the special effects to one of each speaker. As the 99.9% of games are mono, that's a way to improve its performance, or at least try. Even, I would add bass, treble and volume adjustments for each channel in order to have more options.

 

Now there is a database of let's say 6000 mono games. I think it's a good idea to look for ways of improvements to what is already "on hand" i.e. the 6000 mono games, instead of suppose it will be developed from night to morning a replacement database of 6000 quad audio games. And of course I agree and I'm happy to any idea and development, as they give options to choose from.

 

Edited by tane

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Put me down for 1.

I have a p-covox that I have yet to install.    

I think there was supposed an issue with audio mixing levels.   I haven't seen much talk about this add on but I have been away from the atari 8-bit forums for awhile.

I remember seeing the initial hardware announcement for this device but completely missed the first iteration.

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@foft

 

Is it possible, to post or stick the progress for this project here 🙂?

I guess, I´m not the only one, who´s interested in 😉...

 

Thx,

andY

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Well I got boards made, but had some shipping issues. Now some are on the way to Panos to assemble a couple and see if they work. Fingers crossed!

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2 hours ago, foft said:

Well I got boards made, but had some shipping issues. Now some are on the way to Panos to assemble a couple and see if they work. Fingers crossed!

Great news!

 

Thanks for ya feedback!

So please keep us informed 🙂!

 

Gtx.,

andY

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Hi Marc, any updates 😉?

 

I'm absolutely excited to hear any news 😎

 

Gtx.,

andY

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I have decided that, once they're available, one of mine is going into my 576K 32-in-1 800XL. Just cause this is my experimental fun machine and I'm really interested in seeing what the Pokeymax can do.  Then I'll put the real POKEY from that machine aside for safe keeping. 

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13 hours ago, andymanone said:

@foft

 

I don't mean to be impatient, but any news 😊?

A little! Finally got the prototype boards to @santosplast week. I was quite busy and it took a few weeks to send! When he has time he will try to build 1-3 of them which we can then test/use to verify/fix issues. It uses very small parts so I’m not sure how building them will go.

 

If they work and it turns out to be ok to make them, then it might be possible to assemble the other boards from this run.

 

If they don’t then ... it depends. If the fix is clear then I can fix the design and then order new boards, probably fully assembled.

 

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On 10/18/2019 at 3:33 PM, lemiel said:

Thanks. Do you know how I adjust it? I can search for D5 in the binary but the ones I looked at had many addresses. I guess if there is source code it’d be easier.

 

I think to fix sid and/or quad pokey in the pokeymax it’d be best to get a larger fpga. It’d be possible to fit in the smaller one but honestly it’s more work then I think I’ll actually do! Fortunately they are not very expensive.

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1 hour ago, foft said:

A little! Finally got the prototype boards to @santosplast week. I was quite busy and it took a few weeks to send! When he has time he will try to build 1-3 of them which we can then test/use to verify/fix issues. It uses very small parts so I’m not sure how building them will go.

 

If they work and it turns out to be ok to make them, then it might be possible to assemble the other boards from this run.

 

If they don’t then ... it depends. If the fix is clear then I can fix the design and then order new boards, probably fully assembled.

 

Hi Marc, thanks for the update! Sounds great!

 

So I´ll waiting patiently and keep my fingers crossed 🤞.

 

Gtx.,

andY

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