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New pcb for 800XL? It exist.


ZuluGula

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Nice.  Aren't there a few minor inaccuracies in the 800XL Service Manual schematics?  I suppose a part-for-part component swap from a known good 800XL would be the ultimate test of trace accuracy.  Maybe whomever is doing this project also reads AtariAge?

 

I look forward to reading updates as the parts come to him. Thanks for sharing.  :)

 

 

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Although it's a very cool project, I can't  help but feel that cloning the 800XL part for part, is also to clone any issues that it may of had such as DRAM noise and poor ground planes that have been known to produce jail bars in video. It also means that you need to use considerably more parts over a revised design. By moving to 64K of SRAM,  a lot of extra logic and discrete components can be eliminated, and major noise reduction improvements will come along with it. Plus with that extra room, IDE can be easily added into the main board... powered by SDX.

 

All of this is possible and readily available in the public domain release of the 1088XLD schematics. Edit: just add a pair of CD4051's instead of the TK-II CHIP and you can scan the stock keyboard instead.

 

The proven design is there, and it doesn't  require a U1MB to do what I am suggesting. Speaking of which, if you look at the the U1MB page on that schematic, you'll  see the pinouts reflected for the original OS ROM and MMU chips. And the Basic ROM connections can be easily deduced. A drop in PCB with an 800XL footprint could be based upon this. Of course if you just happen to create a footprint that supports a U1MB plugging straight in, then you have an easy choice to make regarding upgrading down the road ;) .

 

But before anyone jumps to the conclusion that I would layout such a board, let me firmly deny any interest in doing so :)

 

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  • 4 months later...
On 12/25/2019 at 3:45 AM, mytek said:

Although it's a very cool project, I can't  help but feel that cloning the 800XL part for part, is also to clone any issues that it may of had such as DRAM noise and poor ground planes that have been known to produce jail bars in video. It also means that you need to use considerably more parts over a revised design. By moving to 64K of SRAM,  a lot of extra logic and discrete components can be eliminated, and major noise reduction improvements will come along with it. Plus with that extra room, IDE can be easily added into the main board... powered by SDX.

 

All of this is possible and readily available in the public domain release of the 1088XLD schematics. Edit: just add a pair of CD4051's instead of the TK-II CHIP and you can scan the stock keyboard instead.

 

The proven design is there, and it doesn't  require a U1MB to do what I am suggesting. Speaking of which, if you look at the the U1MB page on that schematic, you'll  see the pinouts reflected for the original OS ROM and MMU chips. And the Basic ROM connections can be easily deduced. A drop in PCB with an 800XL footprint could be based upon this. Of course if you just happen to create a footprint that supports a U1MB plugging straight in, then you have an easy choice to make regarding upgrading down the road ;) .

 

But before anyone jumps to the conclusion that I would layout such a board, let me firmly deny any interest in doing so :)

 

I still think we need something like the Ultimate64.  A nice FPGA based system that has all the mods integrated into the motherboard. 

VBXE, Rapidus, U1MB, PokeyMax quad + covox, maybe even throw on the SIDE3.  fit all into an 800xl case with Cherry MX keyboard with the same 800xl layout.  Oh, and it needs to have a PAL/NTSC switch...

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7 hours ago, Rybags said:

Nice but yeah, among other things would want to price compare with something like 1080XEL.

But at the least it would be good to have a design in place for when our boards start to delaminate and fail.

I think we'll likely de-laminate and fail way before our Atari's do ? .

 

2 hours ago, Allan said:

It would be nice to have a board that fit into an 800XL case but was also designed to work with the modern upgrades requiring the least amount of soldering. 

So this brings us back around to a 1088XLD with a new layout having all the connectors located to mate up with all the original holes in the 800XL case, and implementing the card fingers for PBI. With careful arrangement of Sally, Antic and the GTIA, modern upgrades would fit with ease. And the XLD design already incorporated headers with the prerequisite signals for these upgrades. Plus the U1MB plugs right in with no soldering or cables what-so-ever, MIDI and a built-in MIDI Synth is already supported if so desired, along with enhanced UAV standard video, which is also a wireless no solder plug-in. Built-in IDE is there as well. Probably want to change the design to use a PokeyONE instead of the dual Pokeys, which would also yield more board space for other things. And while you are at it, building in FujiNet would be the ticket.

 

Another option would be a redesigned Eclaire motherboard in the 800XL footprint.

 

Unlike many years ago where stuff like this was bantered around, but no one could be bothered to draw up a schematic or prototype a design, we now have proven well documented examples --- essentially creating a road map. And I know there are many others out there that have the PCB layout skills required for such a task, some much better than I. So all it takes is for someone to step up and begin the work.

 

Anyone ready to rise to the challenge?

 

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22 minutes ago, mytek said:

I think we'll likely de-laminate and fail way before our Atari's do ? .

 

So this brings us back around to a 1088XLD with a new layout having all the connectors located to mate up with all the original holes in the 800XL case, and implementing the card fingers for PBI. With careful arrangement of Sally, Antic and the GTIA, modern upgrades would fit with ease. And the XLD design already incorporated headers with the prerequisite signals for these upgrades. Plus the U1MB plugs right in with no soldering or cables what-so-ever, MIDI and a built-in MIDI Synth is already supported if so desired, along with enhanced UAV standard video, which is also a wireless no solder plug-in. Built-in IDE is there as well. Probably want to change the design to use a PokeyONE instead of the dual Pokeys, which would also yield more board space for other things. And while you are at it, building in FujiNet would be the ticket.

 

Another option would be a redesigned Eclaire motherboard in the 800XL footprint.

 

Unlike many years ago where stuff like this was bantered around, but no one could be bothered to draw up a schematic or prototype a design, we now have proven well documented examples --- essentially creating a road map. And I know there are many others out there that have the PCB layout skills required for such a task, some much better than I. So all it takes is for someone to step up and begin the work.

 

Anyone ready to rise to the challenge?

 

This would be fantastic.  One of the main reasons (okay beyond cost, the only reason) I have not yet ordered a 1088xel is due to it not being in an old case.  I mean if I am going to 'cheat' with a modern implementation, I want it hidden!

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And to add to what I wrote...

 

The PBI should be fully buffered which takes 3 chips to do. Because a non-buffered system bus heading out to the outside world is quite ridiculous and just plain poor engineering. All to save about $2 ? .

 

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1 minute ago, mytek said:

And to add to what I wrote...

 

The PBI should be fully buffered which takes 3 chips to do. Because a non-buffered system bus heading out to the outside world is quite ridiculous and just plain poor engineering. All to save about $2 ? .

 

This reminds me, while I have my 800 opened up and being operated on; I noticed it has an edge connector by the Personality board slot.  I'm guessing that's for testing (when asked about a similar edge connector on the Apple IIGS that's what I was told it was for).  Anyone think of something cool to do with that?

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  • 4 months later...
3 hours ago, seastalker said:

I would love to buy a new XL board. I haven't looked in a while if the layouts differ, but it would be cool if one board could fit in a 600, 800 and 1200.  Even if just one computer, I'd get it, especially if the mods and upgrades are built in.

Layouts are definitely different for the 1200.  Between the 600xl and 800xl I would have to look exactly at what wouldn't reach if you made a 600xl board in an 800xl's case.  As they are a few inches off in the back.

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  • 4 months later...
10 minutes ago, kheller2 said:

Odd... 9 hours ago the design was updated

"Latest Gerber files include the fixes from my original design."

That's not odd. They just added a comment to the people to clarify that the aformentioned issues are indeed ironed out and included in this design.

Edited by ivop
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This is a very cool project! I love the idea of remake PCBs in general. Especially so for those that include the ability for more modern upgrades like S-Video or even HDMI. I'd love to see the Genesis model 1 get this treatment too. Maybe this 800xl will get forked so a streamlined pcb that fits all/most A8 computers will happen one day. Many thanks for this PCB! 

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  • 2 weeks later...

So I got black one with gold plating. I might have 3 (maybe 4) for sale in US. Anyone can help me to find boxes that there are abou 16x9x2 inches in size, and what would be the best way to ship it?

My rough estimate for BOM is around $200 for PAL and $170 for NTSC plus shipping, all new parts from Best/Digikey/China/Europe. If you have a working donnor, the BOM should be around 1/3 of that.

I'm considering ordering more in some crazy colour like purple or yellow, if there will be any interest (20 people). I'm considering making a kit with some parts that you have to source from Europe and China, so you will have to only order the rest from Best and Digikey or use a donor. I will have new SIO sockets, joystick ports, keyboard connector and power switches.

 

800XLpcb.jpg

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