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I have working two tone mode examples here:

 

You will require real hardware for these as they will not work properly under the current ProSystem and A7800 emulation.  I also suspect that POKEYOne will also not play these, but I would appreciate them being tested.  This is relatively unexplored POKEY territory.

 

The tracks are the opening theme of the SNRS game Super Mario World,  and the theme from the NES game 3D Worldrunner. 

 

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10 hours ago, Synthpopalooza said:

I have working two tone mode examples here:

 

You will require real hardware for these as they will not work properly under the current ProSystem and A7800 emulation.  I also suspect that POKEYOne will also not play these, but I would appreciate them being tested.  This is relatively unexplored POKEY territory.

 

The tracks are the opening theme of the SNRS game Super Mario World,  and the theme from the NES game 3D Worldrunner. 

 

Interesting.


Well, I expect to have a PokeyONE in hand next week, which I intended to test in my 1088XEL or XLD as the right (stereo) POKEY. I don’t have any way to test 7800 code on real hardware (no flash cart, nor CPUwiz’s dev cart).  

 

I will discuss progress on “full” POKEY emulation with the project developer when we meet next week as well. 

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22 hours ago, sramirez2008 said:

Received my POKEY from Best Electronics today.  I sent an email on Sept. 10th and received the chip today, Sept.13th.😊  

 

 

Best POKEY.jpg

I've gotten one from there before too.  I've always been very happy with Bradley's service.

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So this made its way to me today ...

 

I just wish I had a way to test 7800 games with it. Harrumph. Has anyone mentioned that we *really* need an affordable and available 7800 flash cart solution? :)

IMG_2199.JPG

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1 hour ago, DrVenkman said:

So this made its way to me today ...

 

Is this V1 or V2?  I'm waiting on a V2 so that I can try it in my CC2 and Donkey Kong PK. 

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9 minutes ago, SS said:

Is this V1 or V2?  I'm waiting on a V2 so that I can try it in my CC2 and Donkey Kong PK. 

I'm not familiar with that terminology. Are you instead referring to PokeyMax?

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5 minutes ago, DrVenkman said:

I'm not familiar with that terminology. Are you instead referring to PokeyMax?

Sorry, yes, my fault.  I was thinking of PokeyMax instead. Duh.  :party:

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2 minutes ago, SS said:

Sorry, yes, my fault.  I was thinking of PokeyMax instead. Duh.  :party:

Yeah, different implementation of the same idea. Currently I have this one plugged into the Right POKEY socket of my 1088XLD and I'm digging through my thousands of archived titles looking for that lovely "(stereo)" after the title to try it out. :D 

 

 

 

If the price is right, something like this would make the 7800 homebrew scene so much more vibrant. :) 

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We need a sd cart.. can someone poke Fred and see if he is still interested in his inventions? He has been gone!! 

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I tested a PokeyONE today with Bentley Bear's Crystal Quest, Super Circus AtariAge, Pac-Man Collection, Beef Drop, and Froggie.  Works great in all of them!  I can notice a very slight difference in the audio between a real POKEY and the PokeyONE.  Would be less noticeable if I wasn't doing side-by-side comparisons of the games.

 

pokeyone_1.jpg

 

Won't fit in a cartridge with the socket (a regular POKEY does), but should be fine without one.

 

I'm not sure how many people are willing to pay $40+ for POKEY-enabled versions of games.  It's not only the cost of the PokeyONE, but I'm using a more expensive board that requires additional parts as well for these games (although for non-bankswitched games I can reuse Ballblazer boards when I have them, but that still requires desoldering of parts first). 

 

It's very cool to finally play with a POKEY replacement, at least one that is suitable for 7800 games. 

 

 ..Al

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Is $40 really that outrageous anymore?

I'm seeing real Pokeys go for that on eBay now. 

The only place at all I know where to get them for less is Best Electronics.  I've gotten one from there myself.  But he lists it as "1 per customer." 

Is that one per customer ever? Or just one per order?  I don't know. 

All I know is.... I do want to get more Pokey-enabled 7800 games.  And if the PokeyOne works in them, and it is too difficult to find real Pokeys anymore... then that's the route I'll probably end up taking to get those games. 

 

If anyone knows of a better way of getting Pokeys, let me know.   I don't think spending a summer traveling around flea markets looking for Ballblazers is a good alternative.  *shrug*

 

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I'm planning on getting some PokeyONEs before PRGE so I can make some copies of Bentley Bear's Crystal Quest and Super Circus AtariAge for the show. 

 

 ..Al

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Very cool to see this!  Given the scarcity of the POKEY chips and how expensive they are becoming, $40 for these doesn't sound too high of a price. 

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Just now, swapd0 said:

Just asking, It isn't cheaper to build a board with a microcontroller powerful enough to run a POKEY emulator?

 

Show us both a microcontroller-based POKEY emulator that works and is available for a DIP-40 form factor and 7800 cart boards. Of course, if you’re designing new boards from scratch, you can do whatever you like (see eg RIKKI & VIKKI, but as wonderful as that is, that’s not POKEY emulation and won’t work for games coded to expect and use a POKEY chip. 

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46 minutes ago, swapd0 said:

Just asking, It isn't cheaper to build a board with a microcontroller powerful enough to run a POKEY emulator?

 

Actually no. This is a perfect example of an application where a FPGA is a much better choice than a microprocessor.

The digital subsystems in a real POKEY do a lot of things all at the same time. To properly emulate a POKEY in a microprocessor, you need to execute all the required instructions sequentially such that your emulated POKEY correctly changes state every 559 ns (one clock cycle at 1.79 MHz). There are enough instructions that, to meet this timing constraint, the processor has to be running pretty fast. Not sure how fast, exactly, but my guess is at least a few hundred MHz, and microprocessors that can run that fast aren't cheap. I expect you'd also need an external clock source, and those aren't cheap either.

In an FPGA, all the digital subsystems run in parallel, just like in the original POKEY, so with the right "code" (i.e. hardware description, in Verilog or VHDL), you can meet the performance specs with a $3 FPGA running off of the 1.79 MHz system clock.

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This is a random stereo demoscene disk I picked out this afternoon. I recorded the stereo audio directly from my 1088XLD and 1088XEL boards (both also built by me). The signal chain is from the two audio chips inside each computer, through the transistor and cap balancing circuit inside each one and out through a standard 3.5mm jack built into each computer.

 

I couldn't find the right combo of cables around my current mess to record the tracks through my PreSonus audio interface, but my laptop has a combo input jack that allows stereo recording through the on-board audio chip. So the signal may have a tiny bit more digital noise than if I'd been able to get it through my interface but I couldn't discern it with my ears.

 

Anyway, I recorded each track for about two minutes - I couldn't figure out in Reaper (Windows DAW software) how to get the samples perfectly lined up, so there's a tiny fraction of a second offset between the tracks (like a tenth or second or less) - sorry about that; it's been a long while since I've done sample-perfect signal analysis, and this software isn't one I've used extensively.  

 

Below, I've included the track as recorded from each machine as well as the ATR in case you want to run it on your own machines for comparison.

 

One of these tracks is POKEY/PokeyONE, and the other is POKEY/POKEY.  Can you tell which is which?

Track One.wav Track Two.wav Taku-ardo (1998)(Taquart)(Pl)[stereo].atr

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I just figured out how to force Reaper to record track as stereo rather than mixed-down to a single mono track. I'll redo these tomorrow so folks will be able to do a better "apples to apples" comparison with the waveforms visible for each. So everyone hang onto your votes or thoughts. 

 

One other thing of note - one of these is recorded from my 1088XEL and the other is my 1088XLD - without consulting the schematics again tonight, I *think* the audio output circuits are identical but I'll take a look at that again tomorrow too just in case that might affect things. 

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PokeyOne works wonderfully.  Whatever difference, it is subtle. Much more insignificant than what is found and discussed regarding the audio among different versions of the Sega Genesis console.

 

I would go as far as saying, BITD, if a cheaper POKEY clone/substitute was actually made and utilized, the sound difference may have been the same, if not considerably worse.

 

Bravo! Cost considerations aside, between what DrVenkman posted, and Al's review of the chip, it seems we have a winner.  Although, I would love to hear how well it performs against some of the more less used sound options of the POKEY.  Synthpopalooza has really been tapping some awesome features and sound in the thread linked earlier.

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55 minutes ago, Trebor said:

Bravo! Cost considerations aside, between what DrVenkman posted, and Al's review of the chip, it seems we have a winner.  Although, I would love to hear how well it performs against some of the more less used sound options of the POKEY.  Synthpopalooza has really been tapping some awesome features and sound in the thread linked earlier.

Some of those techniques won’t work, I think. Synthpopalooza has indicated that at least some of them utilize stuff usually purposed for serial I/O (yeah, it’s all a black box to me - dunno what he means exactly ... ). So for those we’ll have to wait until feature-complete clones like PokeyONE or POKEYMax become available at a lower price point, it seems to me.

 

Anyway, I did manage to grab stereo tracks for both of these setups last night, and got them edited to line up the samples about as perfectly as I could be eye - I haven’t figured out the automated tools to line up samples yet. But then after all that, I never posted the new samples. I’m on a tablet now, but I’ll do that later today.

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16 minutes ago, Jinks said:

Was track 2 hokey? Anyone else bother to guess.

I told you to hold your guesses. True stereo tracks coming later today (not stereo tracks recorded as mixed-mono). :)

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