The Worlds Smallest Atari 8-Bit?

[cobracon]

3 minutes ago, Stephen said:

Center positive, 2Amp, 2.5mm * 5.5mm barrel (taken directly from schematic).

Thank you very much!!

 

[Bee]

I'll try to peel mine open tonight and get some readings.  

 

Thank you

[NISMOPC]

This might be an elementary question, but I've had my 576NUC+ w/Fujinet-Cart for a few weeks now and am not sure what the mini USB and volume or contrast knob are for on the rear.

 

What is the functionality of those two items? 

Edited April 8, 2022 by NISMOPC

[Mr Robot]

The volume dial is SIO audio/SAM etc. volume, the mini USB is the port for firmware upgrades like the one on the external Fujinet (though you do still need to press the A button when you turn it on to go into update mode. 

 

 

[NISMOPC]

16 hours ago, Mr Robot said:

The volume dial is SIO audio/SAM etc. volume, the mini USB is the port for firmware upgrades like the one on the external Fujinet (though you do still need to press the A button when you turn it on to go into update mode. 

 

 

THANK YOU! - I bought FTDI USB cable a while back thinking that was only way to update the internal FUJINET not knowing it had same feature as the standard SIO FUJINET (which I also own). 

[+mytek]

54 minutes ago, NISMOPC said:

THANK YOU! - I bought FTDI USB cable a while back thinking that was only way to update the internal FUJINET not knowing it had same feature as the standard SIO FUJINET (which I also own). 

You would still need that if you were wanting to update the simpler NUC-FujiNet only daughter board, since it has no built-in USB/Serial conversion circuitry, which the FujiNet/Cart board does have.

 

[NISMOPC]

9 hours ago, mytek said:

You would still need that if you were wanting to update the simpler NUC-FujiNet only daughter board, since it has no built-in USB/Serial conversion circuitry, which the FujiNet/Cart board does have.

 

Good to know - I have the FUJINET-CART board so I am good to go! Thanks @mytek 

[Bee]

OK - I have found my issue on the fujinet cart board.  The PSU and my solar inverter don't play well together and make dirty power.  Just befre tearing everything down.  I decided to move it to a location it could use a "wall plug."  Once on City power with this PSU 100% no problems.  I will go back to muy solar rig and bypass the AC/DC psu and try it on 12 Battery power.  I bet there will be no issue.  I wanted to report back so no one would look any further at this one.  Good to go & great fun.  I really love this retro stuff.  Keep flipping 8 bits at a time.

 

Thank you 

[Panther]

Thanks to the prototype 576NUC+ boards that mytek sent me so that I could scavange the PIC16F1847-I/SO MCUs and other components off of them, I was able to get the first of my two NUC boards assembled.  This one is destined to be a PAL system, but while I wait for my PAL oscillator to arrive from Best Electronics, Ive installed the NTSC components for now.  After completing the build, I wasn't able to get the NUC to power on.  It turns out that it's a good idea to not blame the NUC without testing the keyboard.  A problem key has been fixed.

 

The other issue I had was that I couldn't program the PIC16F1847.  With my PICkit 3 connected, my PICkit3Plus software (this is a nice alternative to MPLab when you just need something more basic) would always indicate that there were no devices found.  I checked the connections between the J7 header and the PIC, but everything looked fine.  The programmer could also detect when the board was powered on, so the power part of the circuit was fine too.  This lead me to the PGC/PGD connections.  These are shared with the reset and option lines, which connect to multiple Atari chips (especially the reset).  I simply removed all the Atari chips and found that I could now communicate with the PIC16F1847 over the J7 header.  Actually, one of the chips wasn't really an Atari chip, as I'd used a Western Digital W65C21N for the PIA, which of course turned out to be the culprit.  I replaced this with a standard Atari PIA and programming the PIC was no longer an issue.

 

On my next build I will test powering the board on and off via the keyboard before installing any Atari chips.  This will confirm whether the basic power circuit and PIC MCU are functional.

 

The 576NUC+ is an incredibly nicely designed device, and I can't imagine the amount of work that must have gone into these, especially all the routing required in such a tight space, while managing to keep the signals nice and clean, especially video.  Congratulations Michael and everyone else involved on such a nice compact Atari design.  And thank you again for the components.  My NUC boards would still be sitting in a box collecting dust for weeks or maybe even months before I could have acquired the chips.

 

Now, I am having one glitch on my NUC that I still need to figure out, and that's that the video signal seems to be out of sorts.  Oddly, when I first tested it briefly using a composite signal, the KanexPro video converter I have at my bench showed a signal without a problem.  But then I later found that it would frequently have trouble getting a sync, and s-video doesn't work at all.  The RetroTink-2x I also have at my bench can't get a sync at all even on composite.  I'll work on sorting this out later today, then I can test out this 576NUC+SDrive!

 

[+mytek]

30 minutes ago, Panther said:

Now, I am having one glitch on my NUC that I still need to figure out, and that's that the video signal seems to be out of sorts.  Oddly, when I first tested it briefly using a composite signal, the KanexPro video converter I have at my bench showed a signal without a problem.  But then I later found that it would frequently have trouble getting a sync, and s-video doesn't work at all.  The RetroTink-2x I also have at my bench can't get a sync at all even on composite.

Hopefully it won't be too much of a pain to figure out. Good thing is with this no longer being a prototype design, and thus proven, you know its got to be something basic that is creating the problem. And since most of the video circuit is composed of passive components, that help's narrow it down to only a few active devices. Sync issues would primarily be caused by a problem with one of these three devices U19 (SN74AHCT14DR), U15 (FMS6400), or the Schottky diode D3 (reversed?). Also don't rule out the GTIA chip.

 

[Panther]

Yeah, I've been staring at that page of the schematics for a little while.  I couldn't wait and decided to troubleshoot some more.  D3 wasn't backwards, but the sync was fine until D3 and failed to  get added to LUMA.  I tested D3, it didn't look good.  Took a closer look...okay, this one is my fault, it looks like I put too much stress on that diode when I installed the socket next to it and it's cracked.  Replaced, works great now!

 

[Panther]

There doesn't appear to be a disk swap function between the TK-II and SDrive-NUC, and no physical button.  Since the SDrive-NUC was designed to fit the same layout as the FujiNet in terms of the SD slot and LEDs, I'm a bit surprised that buttons weren't included for disk swap and whatever else.

[+mytek]

1 hour ago, Panther said:

There doesn't appear to be a disk swap function between the TK-II and SDrive-NUC, and no physical button.  Since the SDrive-NUC was designed to fit the same layout as the FujiNet in terms of the SD slot and LEDs, I'm a bit surprised that buttons weren't included for disk swap and whatever else.

Well the basis for the drive was called SDrive-Simple in the non NUC implementation for a reason. And to be fair this is based on the SDrive-Max firmware, so unless you also want an LCD touch screen, there was no way to simple connect a push button switch to swap disks. But realistically how often do the majority of users actually need to have this? I remember being all excited when developing the XEL-CF3 that we were now going to have this fantastically great disk swap function. Well after testing it and demoing it for several people, I settled into using this new CF drive and established my actual usage. Low and behold I never found the need to use the swap button ever again. Of course other people's requirements will vary from mine, but I also wouldn't be surprised if a lot people end up just like me. Perhaps if you are a diehard gamer that loves the crap out playing multi-disk games, you will miss this feature.

 

Anyway this isn't the first time I've heard someone's disappointment of not having a swap button, and I'm sure it won't be the last. Good thing I like it for what it does do, after all I'm the guy who this was created for, and then decided to share it with others while making zero $$$ for the effort

 

Panther please don't take any of this babbling the wrong way, because you simply asked the question out of curiosity. But when looked at from my perspective here's the conversation I keep having over and over again...

 

ME

"Hey look what I designed and piggy-backed on the great work of Bob!k, Raster, and KBr."

"It's meant to be installed internally so as to leave the SIO port free for other devices."

"It embodies the basic functions of a disk drive,  while being able to mimic up to 4 floppies on the SIO bus."

"it can use either Standard Size SD cards or with a simple adapter Micro-SDs."

"And due to its simple hardware implementation, it's very inexpensive."

 

RESPONSE

"But where's the Swap Button?"

 

i've seen this scenario repeat itself many times over in my Atari upgrade development career. I'm always held to this notion if product XYZ had a feature I've left off, that's what people always love to focus on. Nothing else seems to matter. Wow it's amazing to me that people aren't shooting themselves in the head for buying a car that is missing a feature that some other car has

 

Oh and before I forget, no you can't load cassette tape files or something other than XEX or ATRs. Boy I sure do miss my cassette tape days, NOT! I couldn't wait to save up enough money to buy my first disk drive. but after doing so there was no looking back   I also feel the same way about using real floppies instead of an SD or CF card.

 

EDIT: I think in the future I'll just provide a link to this post if I get asked about the missing swap button

 

Edited April 10, 2022 by mytek

[+mytek]

2 hours ago, Panther said:

Yeah, I've been staring at that page of the schematics for a little while.  I couldn't wait and decided to troubleshoot some more.  D3 wasn't backwards, but the sync was fine until D3 and failed to  get added to LUMA.  I tested D3, it didn't look good.  Took a closer look...okay, this one is my fault, it looks like I put too much stress on that diode when I installed the socket next to it and it's cracked.  Replaced, works great now!

Opps just saw this post.

 

Great news ?

 

The funny thing is, I was thinking about also suggested not only a reversed diode, but an open one as well. However I thought that very unlikely, not thinking about the possibility of physical damage to the diode that could cause this condition. Great find on your part, and now your back in business

 

[Panther]

Sorry, I'm busy laughing.  An excessively cited detail, got it!  The SDrive you created works great, I was just surprised it didn't have that.  Hey, I recently replaced my fairly new car because I was annoyed that it lacked certain features.  Seemed a better option than shooting myself in the head.

 

Tapes...I don't understand how anyone can be nostalgic about tapes, so I'm with you on that!  I have some really great disk drives, including a Mega Speedy 1050, but I don't remember the last time I used a disk.  It's been years.

 

If I really feel I need that swap button then I'll just make a new SDrive.  ?

 

 

[Panther]

14 minutes ago, mytek said:

?

 

The funny thing is, I was thinking about also suggested not only a reversed diode, but an open one as well. However I thought that very unlikely, not thinking about the possibility of physical damage to the diode that could cause this condition. Great find on your part, and now your back in business

I couldn't even see the crack until after I realized there was a problem and gently pried at it, causing it to split.  It wasn't that it wasn't making any connection, just not a good one, until it separated anyway.

 

 

[+mytek]

1 minute ago, Panther said:

I couldn't even see the crack until after I realized there was a problem and gently pried at it, causing it to split.  It wasn't that it wasn't making any connection, just not a good one, until it separated anyway.

That's why you were seeing intermittently good and not so good video

 

[AtariGeezer]

Finally bought a 576NUC+ :)

 

First got the standard case, then upgraded to the FujiCart option.

 

 

Now I have all of @mytek's trio of A8 Computers

 

I added a Sophia 2 to the 1088 XLD.

 

Thanks @mytek for designing these and making the schematics and design files free to the public.

And to @MacRorie for selling me the cases, needed modules and building me the NUC boards

 

Jay

 

[Panther]

My PAL crystal finally arrived, so I replaced the NTSC version in my NUC, swapped out the ANTIC and the GTIA, adding the PAL color burst board.  My PAL 576NUC+ is complete.  It's even in a case now, but now I need a new case because I decided to use the SDrive instead of the FujiNet board.

 

[cobracon]

Hey all. Been playing around with the new nuc+ that I got from The Brewing Academy. I seem to be having an issue that I can't correct. I bought the av cable from them, the one that works with atari and ti/99. I am have major noise coming thru the audio. Almost like a bad rf connection when using an old tv. I have all the proper colors plugged in. There is a left over black plug. Am I doing something wrong? I had to turn the volume off and run with no sound.

 

Thanks

[Panther]

2 hours ago, cobracon said:

Hey all. Been playing around with the new nuc+ that I got from The Brewing Academy. I seem to be having an issue that I can't correct. I bought the av cable from them, the one that works with atari and ti/99. I am have major noise coming thru the audio. Almost like a bad rf connection when using an old tv. I have all the proper colors plugged in. There is a left over black plug. Am I doing something wrong? I had to turn the volume off and run with no sound.

 

Thanks

Is the video output nice and clear?  Do you hear the audio sounds you expect to in addition to the static?

 

Also, what about the bell and SIO sounds?

Edited April 16, 2022 by Panther

[cobracon]

23 minutes ago, Panther said:

Is the video output nice and clear?  Do you hear the audio sounds you expect to in addition to the static?

 

Also, what about the bell and SIO sounds?

The video looks good. I do hear some audio. Not getting any sio or bell sounds

 

[Panther]

I suspect the transistor at Q2 (PN2222), but I would expect there to still be some SIO and bell sounds since these all join before Q2.  Still, might have a look around it and make sure the connections are all good.

 

[cobracon]

21 minutes ago, Panther said:

I suspect the transistor at Q2 (PN2222), but I would expect there to still be some SIO and bell sounds since these all join before Q2.  Still, might have a look around it and make sure the connections are all good.

 

Well I found the problem. The black cable is the audio. I don't know why it is but it is. Thanks for the help!

[+mytek]

7 minutes ago, cobracon said:

Well I found the problem. The black cable is the audio. I don't know why it is but it is. Thanks for the help!

What cable do you have - gotta picture?

 

EDIT: I reacted with a laugh at your post, not that I'm laughing at you, but the fact that on a cable I have the black RCA is composite video - go figure. I don't think there is any standard color code on these kind of A/V cables.

 

Edited April 16, 2022 by mytek