Hi all,
I am about to upgrade my ATARI 800XE (64x4) to 128kb of RAM and have problems sorcing a C025953 chip.
The missing RAM chips (TMS4464-10) have been arrived already and I soldered in the missing sockets for the RAM and the C025953 chip already.
Does someone know where to order this EMMU chip?
I ve read something about a GAL solution as well, but there is no U35 on my board, so I am struggeling here.
Upgrading an ATARI 800 XE to 128KB of RAM
-
- Posts: 29
- Joined: Fri Jul 17, 2020 2:20 pm
- rubber_jonnie
- Moderator
- Posts: 3208
- Joined: Thu Aug 17, 2017 7:40 pm
- Location: Essex
- Contact:
Re: Upgrading an ATARI 800 XE to 128KB of RAM
I got mine from ebay, AtariFreakz if I recall.
Have a read here it may help: viewtopic.php?f=44&t=160
Have a read here it may help: viewtopic.php?f=44&t=160
Collector of old Atari things:
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2

Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk
Re: Upgrading an ATARI 800 XE to 128KB of RAM
I see no point of upgrading 800 XE to 128kB. Go straight for Compy Shop 512kB or RAMBO 1MB.
I have the same board, and even after replacing GTIA to one that worked ok on 2 different boards, on this board, acts as faulty, (at least until I rerouted one of the clocks). I don't like this board also for a horrible picture quality.
I have the same board, and even after replacing GTIA to one that worked ok on 2 different boards, on this board, acts as faulty, (at least until I rerouted one of the clocks). I don't like this board also for a horrible picture quality.
- rubber_jonnie
- Moderator
- Posts: 3208
- Joined: Thu Aug 17, 2017 7:40 pm
- Location: Essex
- Contact:
Re: Upgrading an ATARI 800 XE to 128KB of RAM
I agree and disagree with that statement. I upgraded my 65XE to 128MB because of it's excellent original condition and a desire to keep is as stock as possible. I used original Atari parts, and mine was the board that required an additional 8 RAM chips, but I don't use it as much as my 800XL, so that got an Ultimate 1MB upgrade, which is a great addition to the machine.tzok wrote: ↑Thu Jul 23, 2020 12:22 amI see no point of upgrading 800 XE to 128kB. Go straight for Compy Shop 512kB or RAMBO 1MB.
I have the same board, and even after replacing GTIA to one that worked ok on 2 different boards, on this board, acts as faulty, (at least until I rerouted one of the clocks). I don't like this board also for a horrible picture quality.
Collector of old Atari things:
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2

Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk
- rubber_jonnie
- Moderator
- Posts: 3208
- Joined: Thu Aug 17, 2017 7:40 pm
- Location: Essex
- Contact:
Re: Upgrading an ATARI 800 XE to 128KB of RAM
@tzok
Very Interesting pictures to see indeed.
Can ask that you please avoid linking to external sites though and upload to the forum at 800x600 instead, and place inline. If the external source is not available then the pictures will disappear. Thanks.
Very Interesting pictures to see indeed.
Can ask that you please avoid linking to external sites though and upload to the forum at 800x600 instead, and place inline. If the external source is not available then the pictures will disappear. Thanks.
Collector of old Atari things:
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2

Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk