2023 Advanced PCB Remake For the 800XL -- Revision 1.1

[reifsnyderb]

About the PLC chips:

 

I'll be releasing the .jed files soon for them and the source code is already in the draft document I created.

 

Since I re-designed this board, it's easy to forget to mention some things.  So, here's a general description of what PLC's (programmable logic chips) are required.

 

There are at least two PLC chips needed for a board.  These chips are the MMU and the GLU.  The MMU is an ATF22V10 and replaces the normal Atari MMU.  This MMU also examines the R/W line to enable the ROMs only on a read and simulates an open-collector input for the PB Refresh line.  The GLU replaces the 74LS138 used to enable the I/O devices in the $D000-$D7FF region.  The GLU also replaces the memory management chips for the RAM and allows PBI RAM to be activated, if enabled.

 

If only 64k of RAM is going to be used, no EMMU is required as 4 jumpers can be soldered to use 64k only.  That being said, the EMMU can also be configured to supply only 64k of RAM.

The EMMU is required if you are going to use 128k in 130XE mode or 320k in RAMBO mode.  The EMMU also permits you to easily do other memory configurations, such as 16k if you really want to do so for some strange reason.  (The MMU could be programmed to do the same.)

 

Some examples:

 

A basic 64k configuration would require the following:

2 chips:  MMU and GLU

 

A 130XE type configuration with CPU and ANTIC banking would require the following:

3 chips:  MMU, GLU, and EMMU

 

A 320k type configuration, with RAMBO banking, would require the following:

3 chips:  MMU, GLU, and EMMU

 

I'll put this all in the assembly/build document as well.

 

 

 

[Matej]

Beautiful project! Love it.

Have 3x A800XL this will be amazing to have one day 2x of them. And You can evolve with Mytek stereo-ps/2 keyboard https://ataribits.weebly.com/tk-ii-stereo.html to 4mb atx Atari in future.

[kenp]

22 hours ago, reifsnyderb said:

This could be done with a 1090 type card as well.   🙂

I looked up the 1090 and agree the possibility for option cards is much wider but it lacks the mystique of hiding all that power in an old 800 cabinet.  I've been rebuilding old PCs into sleepers the last couple of years so I guess I'm stick in a rut.

[_The Doctor__]

the 800 has room inside the case for sideboards, in fact, a number of in house 800's had them.

Pehaps 1098 ( reduced size 1090 reconfigured for 800 could be a thing since there are already 2 viable PBI mod/devices already available

 

Edited November 27, 2023 by _The Doctor__

[scitari]

Very exciting! Thanks for sharing!

[reifsnyderb]

Working .jed files for the PLC's:

 

MMU/U3:

MMU.jed

 

GLU/U2:

GLU.jed

 

EMMU/U26:

EMMU_16.jed

EMMU_64.jed

EMMU_128.jed

EMMU_128XE.jed

 

[reifsnyderb]

I've got an AS6C4008 ordered so as to test the 320k configuration.  I'll post the 320k .jed file once it has been tested. Also ordered are all the sockets and chips needed for those who are interested in getting a board.

[+ZuluGula]

@reifsnyderb, I'm interested in one board. Thank you.

[reifsnyderb]

Version 0.99 of the "manual":

 

2023 Advanced PCB Remake For the 800XL V11 r099.pdf

[Bee]

i'm interested in a board as well.

 

Thx

[reifsnyderb]

Good news/bad news....

 

The good news is that the chips and sockets came in this morning.  I just tested the 320k configuration, with an AS6C4008, and it works nicely.  So, that's good.  Here's the .pld file and .jed file for 320k.

 

EMMU_320.PLD

EMMU_320.jed

 

Now for the bad news:  I needed 24 pin sockets for the atf22v10's.  I accidentally ordered the wide sockets instead of the narrow sockets.  🤬🤬🤬  (This is the second time I ordered the wrong 24 pin sockets.)

 

It takes at least 2 days to get parts shipped; so I probably won't be able to ship the first batch of boards until Monday.  😞

 

Update:  Sockets ordered (again).  This time, I double-checked all data sheets.  😕

 

 

 

 

Edited November 29, 2023 by reifsnyderb

[Matej]

I am interested 2 boards in spring. Fully assembled if possible.

[reifsnyderb]

47 minutes ago, Matej said:

I am interested 2 boards in spring. Fully assembled if possible.

Fully assembled....as in all components, switches, etc., installed and tested?  I could do so with donor boards and working LSI chips.  It would take many hours for two boards.  Please PM me if this is what you have in mind.

Edited November 29, 2023 by reifsnyderb

[+scorpio_ny]

On 11/25/2023 at 7:14 AM, Rybags said:

Nice, but a question.

Couldn't the overall board size have been significantly reduced and still been retained by the default screw positions given the amount of component reduction?

Though that said, would there be a cost saving to make it worth the effort?

I was thinking about this. If you reduce the board size, it would essentially be building a replacement board for the 600XL 😄.

Edited November 30, 2023 by scorpio_ny

[reifsnyderb]

6 minutes ago, scorpio_ny said:

I was thinking about this. If you reduce the board size, it would essentially be building a replacement board for the 600XL 😄.

A 600XL board could be done.  It would take some time, though.  Some of the breadboard sections would have to be dropped and components stood on end.

[invisible kid]

I was thinking about going the other way, a bigger board with integrated 1090/1091. A case that opens and takes cards. The usual ports plus an XEGS keyboard port. No feature creap, lol. I think there are similar things done already, but not up to date on all of it.

Edited November 30, 2023 by invisible kid

[reifsnyderb]

3 hours ago, invisible kid said:

I was thinking about going the other way, a bigger board with integrated 1090/1091. A case that opens and takes cards. The usual ports plus an XEGS keyboard port. No feature creap, lol. I think there are similar things done already, but not up to date on all of it.

That's quite possible.  The 1090/1091 is nothing but 1/2 a power supply, buffers, and a 5 50 pin card edge connectors.  It's too bad I don't have an Apple IIe lying around.  Such a board would be a great upgrade! 

[Dropcheck]

1 hour ago, reifsnyderb said:

That's quite possible.  The 1090/1091 is nothing but 1/2 a power supply, buffers, and a 5 50 pin card edge connectors.  It's too bad I don't have an Apple IIe lying around.  Such a board would be a great upgrade! 

Sounds like an ATX board implementation with an ATX case.  Definitely feature creep.

[reifsnyderb]

Sockets came in today.  First boards ship out Monday.   🙂

 

[Krystone]

Wow. This is an interesting project. If I skipped something in the posts, don't get mad, but here are my 2 cents: please don't change the board size, please make sure you leave room for most of the extras that have appeared on the scene over the years, yes, mainly the ones that @lotharek offers. Ideally, it would be amazing to have most of these things implemented on the board... Yeah, I know... 

 

PS. I would be interested in an assembled board as well. The key chips, I could place on my own.

Edited December 2, 2023 by Krystone

[reifsnyderb]

Ten more boards ordered today.   🙂

 

[reifsnyderb]

1 hour ago, Krystone said:

Wow. This is an interesting project. If I skipped something in the posts, don't get mad, but here are my 2 cents: please don't change the board size, please make sure you leave room for most of the extras that have appeared on the scene over the years, yes, mainly the ones that @lotharek offers. Ideally, it would be amazing to have most of these things implemented on the board... Yeah, I know... 

 

PS. I would be interested in an assembled board as well. The key chips, I could place on my own.

Many of the extras can be placed.  Some, such as in internal U1MB, would require an adapter board both due to the changes in the MMU and ROM.  (My recommendation here is to use the PBI U1MB, when it is available.)

[Krystone]

Maybe I am dreaming, but if I am, my dream is to have a full size modern motherboard with:

• Pokey MAX or 2 x POKEY (options for routing stereo, or mixing stereo to mono)
• Ultimate 1MB / 4MB
• SAVO
• SDrive (only full size SD card slot, no display)
• Maybe: External keyboard interface, i.e. AKI PS2
• FujiNet
• VBXE (VBXL?)
• COVOX
• SIO2MIDI
• SIO2PC
• O2 Fixer
• USB-C power input (plenty of USB-C power adapters out there)

If it would be possible to implement most of these things in 1 FPGA and some extra circuitry, it would be amazing. Of course, I am not taking into consideration the fact that there might be copyright issues and some conflicts of interests. Like I said, I am dreaming here.

 

Also, worth considering:

• RAPIDUS (or leave room for expansion)

If all of this could be installed in an elegant way into 800XL, it would be a computer better than Amiga

[reifsnyderb]

4 hours ago, Krystone said:

Maybe I am dreaming, but if I am, my dream is to have a full size modern motherboard with:

• Pokey MAX or 2 x POKEY (options for routing stereo, or mixing stereo to mono)
• Ultimate 1MB / 4MB
• SAVO
• SDrive (only full size SD card slot, no display)
• Maybe: External keyboard interface, i.e. AKI PS2
• FujiNet
• VBXE (VBXL?)
• COVOX
• SIO2MIDI
• SIO2PC
• O2 Fixer
• USB-C power input (plenty of USB-C power adapters out there)

If it would be possible to implement most of these things in 1 FPGA and some extra circuitry, it would be amazing. Of course, I am not taking into consideration the fact that there might be copyright issues and some conflicts of interests. Like I said, I am dreaming here.

 

Also, worth considering:

• RAPIDUS (or leave room for expansion)

If all of this could be installed in an elegant way into 800XL, it would be a computer better than Amiga

This is all possible, of course.  Assuming I could get the schematics for everything, it would take a month to design the board and at least 2 prototype boards.  The cost, in time and money, would be pretty high.

[Krystone]

Maybe all of this could be crowdfunded? What sorts of costs are we talking about, or is this a PM question?