A little bit of 8 Bit: 65XE upgrade to 128k RAM

Any 8bit repairs, images, cool things, upgrades etc.
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tfhh
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Re: A little bit of 8 Bit: 65XE upgrade to 128k RAM

Post by tfhh » Mon Nov 16, 2020 8:31 am

aotta wrote:
Sun Nov 15, 2020 11:44 am
Hello everybody! i found this great thread about 65XE ram upgrade, but just discovered mine has a 130XE(64x4) motherboard with unpopulated U11, U12 and U35: since aren't more available on ebay the C25953, is there a way to program a GAL for replacing it?
It´s not so easy to expand this XE mainboard. I would strongly suggest to take a more modern expansion. For power users the Ultimate 1 MB is a good choice (availible at Lotharek) or for example my 512 KB SRAM expansion. If you want to DIY, then take this: Hias SRAM expansion. Depends on what you want and how much money you will spend :-)

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rubber_jonnie
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Re: A little bit of 8 Bit: 65XE upgrade to 128k RAM

Post by rubber_jonnie » Mon Nov 16, 2020 9:18 am

aotta wrote:
Sun Nov 15, 2020 11:49 pm
I have the sdrive max, that I use with 65xe and with my 800xl, but I think I'll upgrade only the 65, because the 800 is boxed and I take it out from its polys rarely, to preserve them!
I'm very interested in VB/XE too, I use RGBtoHDMI for most of my retrocomputer, and I am waiting for the OSSC+koryuu i bought some days ago for digitalizing the composite output of the Atari's ones, but if it won't work as expected, I'll go for the VB/XE solution too!
Neither of mine are boxed, though with the 800XL I was careful when doing the VBXL upgrade to make sure that the case was not altered in any way at all as it's otherwise original, and of course I kept the parts so it can be reverted.

I did modify the case on the 65XE so I could retain the monitor port, and since the modulator was long gone (Never worked well and eventually died) I expanded that hole and put the VBXE connector there, which is a 13 pin connector like that of the ST.

The cable I have is SCART, but it works just fine with my OSSC to HDMI. I do tend to plug direct to TV though as it has SCART anyway, and I use the OSSC for my other stuff.
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

aotta
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Re: A little bit of 8 Bit: 65XE upgrade to 128k RAM

Post by aotta » Mon Nov 16, 2020 2:50 pm

Thank you all for the hints, i've ordered the Ultimate 1Mb and going to desolder the CPU and MMU.
I'll keep the RF modulator since it works fine, and all 65XE's motherboard is in good condition, while the case has some damages, so i'll not worry if i'll have to drill it for a connector if i'd decide to add the VB/XE addon.

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Re: A little bit of 8 Bit: 65XE upgrade to 128k RAM

Post by rubber_jonnie » Mon Nov 16, 2020 4:53 pm

aotta wrote:
Mon Nov 16, 2020 2:50 pm
Thank you all for the hints, i've ordered the Ultimate 1Mb and going to desolder the CPU and MMU.
I'll keep the RF modulator since it works fine, and all 65XE's motherboard is in good condition, while the case has some damages, so i'll not worry if i'll have to drill it for a connector if i'd decide to add the VB/XE addon.
If you're going to keep the modulator, simply remove the original 5 pin connector for the monitor and fit the 13 pin in it's place. Dimensionally it's pretty identical apart from 13 pins instead of 5.

I simply lay the 13 pin connector on it's side once wired up to VBXE and then hot glued it in place on it's side. Doing this means no damage to the mainboard in case you want to go back to the original setup.

This is the socket on my XE:

Video_socket.jpg
Video_socket.jpg (66.62 KiB) Viewed 549 times

And you could simply do the same as I've done at the modulator hole at the monitor port to it's left.

And here is the modified modulator hole:

Resized_Modulator_Hole.jpg
Resized_Modulator_Hole.jpg (66.57 KiB) Viewed 549 times

And how it looks on my 800XL:

800XL_VBXL_Output.jpg
800XL_VBXL_Output.jpg (73.17 KiB) Viewed 549 times

Obviously because of the connector key it means rotating the plug 90 degrees to plug in, but once in, you won't notice, especially if you have a permanent setup.
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

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