Atari 800XL: Ultimate 1MB upgrade

[rubber_jonnie]

Despite upgrading my 65XE to 128kb, I still wanted more, but had always been put off the Ultimate 1MB due to it's cost.

I decided the other day to check, and was happy to see the price had dropped,so I decided to take the plunge and order one. What are the benefits of the Ultimate 1MB I hear you say?

• As solderless as possible (only RW, PHI2, HALT and RESET lines need soldering when MMU and OS rom are socketed)

• Fully flashable SpartaDOS-X with up to 320kbytes for its purposes

• Real Time Clock module for SDX with battery backup and NVRAM

• Fully flashable 4 OS ROM slots

• Hardware WRITE PROTECT for the whole Flash array

• Configurable memory expansion with 4 modes of operation (disabled, 320k RAMBO, 578k COMPY SHOP, 1088k RAMBO)

• Customizable BASIC and MISSLE COMMAND slots (also flashable)

• Compatible with all XL/XE machines (600XL needs 64kB of RAM first)

Of particular interest were the memory options above 128K, which would allow for demos like Numen to be run.

Anyway, mine arrived today:

IMG_20190605_095033.jpg (412.48 KiB) Viewed 7340 times

And I will post details of the surgery for all to see, which will see me remove my Ape Warp 32 in 1 (https://www.atarimax.com/warpos/documentation/) come out in favour of the Ultimate.

The APE Warp will then find a home in my 130XE.

More on this subject soon.

[redhawk668]

Check out this site: https://atari8.co.uk/. Alternative firmware for the Ultimate 1 MB.

[rubber_jonnie]

Yeah, I'd already seen that update thanks, first things first I need to get it installed and running!!

And typical, that site is offline for maintenance right now!!

[redhawk668]

I have one too, crammed into a 600XL I really like the compact design of the 600XL. It started out as a 16Kb machine, all dirty and neglected. Cleaned it up, upgraded it’s RAM to 64kb, ripped out the rusty shield and fitted the Ultimate 1mb. It also has a Sophia RGB modification, crystal clear picture.

[rubber_jonnie]

I have one too, crammed into a 600XL I really like the compact design of the 600XL. It started out as a 16Kb machine, all dirty and neglected. Cleaned it up, upgraded it’s RAM to 64kb, ripped out the rusty shield and fitted the Ultimate 1mb. It also has a Sophia RGB modification, crystal clear picture.

Very nice!

My first Atari was a 600XL, but it had a fault when used with the ram expander and was returned for an 800XL instead.

I've been trying to get another, but it doesn't seem to be so easy

[rubber_jonnie]

The upgrade is progressing nicely and will definitely be finished today. The instructions on Lotharek's website are great, and you should visit his site first before proceeding.

The product page, including installation instructions can be found here: https://lotharek.pl/productdetail.php?id=56

Start by removing the 800XL mainboard from the case. I'm not going to document this, because if you don't know how to dissassemble an 800XL, you shouldn't be attempting this upgrade!

If you are not competent at soldering and de-soldering, then you shouldn't be attempting this upgrade either!

Once the board is on your workbench, you need to locate the OS ROM and the MMU chip. Their locations may vary, but on my board, they are located at U3 (MMU) and U5 (OS ROM).

Also, these chips can either be in sockets, soldered in, or like mine, the OS ROM was socketed and the MMU soldered in. You should be prepared to remove either or both of these chips and fit sockets in their place.

My board had previously been upgraded to Steven Tuckers APE Warp+ 32 OS in one, which will need to be removed prior to installing the Ultimate 1MB. Its likely that most people won't have APE Warp+ as I do, so just assume where I mention APE Warp+ I mean OS ROM.

Here is the board as removed and ready to start the process:

Before.jpg (174.24 KiB) Viewed 7243 times

Where I have indicated APE Warp+, this is where you will find the OS ROM. If the OS ROM is in a socket, carefully remove it taking care not to bend any pins, and carefully store it, making sure you mark it. You won't need it again, but it is worthwhile keeping it safe.

If the OS ROM is soldered in, carefully de-solder the chip and remove. Remember these boards are 40 odd years old, so take great care not to damage the board with too much heat. I also had to desolder the 3 wires that were part of the APE Warp+ installation.

Once the OS ROM is removed (And a socket installed if not present), U5 will look like this:

APE_Removed.jpg (144.74 KiB) Viewed 7243 times

Next locate U3, the MMU. It is the only 20 pin chip on the board, and is located just in front of the cartridge slot. It will most likely be soldered in, so carefully desolder to get to this stage:

U3.jpg (153.69 KiB) Viewed 7243 times

Finally Solder in a socket in place of U3:

MMU_Socket.jpg (130.4 KiB) Viewed 7243 times

Now you're ready to start fitting the Ultimate 1MB.

[PhilC]

Great guide RJ.

I'll have to dig my 800xl out to check, lol.

Already upgraded that to 1mb with this kit.

[rubber_jonnie]

Great guide RJ.

I'll have to dig my 800xl out to check, lol.

Already upgraded that to 1mb with this kit.

Thank you More to come later today.

[rubber_jonnie]

Ok, here we are, part two final fitting and reassembly!

First, you will need to solder 4 wires from the supplied connector to the CPU as per this diagram:

cpu.jpg (83.61 KiB) Viewed 7208 times

Credit to Lotharek for this diagram.

And it will end up looking something like this:

CPU_connection.jpg (133.11 KiB) Viewed 7208 times

Since the Upper shield can no longer be fitted due to lack of space (Unlees you decide to cut it), that can be set aside. We will refit the lower shield, but since the Ultimate 1MB comes with a fitting kit that includes a long nut/bolt and a stand off, we'll need to make an extra hole for it to go through, as the nearest one is for screwing the mainboard to the lower case.

Temporarily fit the lower shield and fit the mainboard to the lower case, on on the right hand side, between the joystick port and the cartridge port, note the hole in the motherboard that is blocked by the lower shield, and mark the holes position on the lower shield with a marker pen. Remove the board and lower shield from the lower case, remove the lower shield from the mainboard, and drill a new hole where you just marked, like this:

Lower_Shield.jpg (106.68 KiB) Viewed 7208 times

Then refit the shield to the mainboard using the original screws, screwed in from the top side of the mainboard and not the bottom. Put the long bolt from the Ultimate kit through the board, and screw one of the supplied nuts all the way down. This will create a post to mount the Ultimate 1MB on.

Next fit the supplied cables to the MMU and OS ROM sockets. Pay careful attention to the orientation of pin 1 (Cable with red stripe) and ensure it matches pin 1 of the socket. The DIL connectors on the cables also have pin numbers marked on the top:

Fitting_cables.jpg (146.9 KiB) Viewed 7208 times

Now plug the cables into the Ultimate 1MB and route the cables then use the last nut to hold the PCB in place on the bolt you inserted earlier for this purpose. Trim the standoff as required to ensure the PCB is level with a single layer of ribbon cable across the top of the DIL adaptor.

I originally routed the cables like this:

MMU_No_Good.jpg (165.4 KiB) Viewed 7208 times

But discovered that the cartridge doors wouldn't open fully:

Blocked_Door.jpg (73.26 KiB) Viewed 7208 times

I therefore had to route the cables like this in order for the cartridge doors to be clear:

MMU_Cable.jpg (128.58 KiB) Viewed 7208 times

Once correctly routed, I was able to reassemble the 800XL (Sans top shield) and test it.

Booting with 'HELP' pressed brought me to the following setup screen:

Ultimate_Setup.jpg (84.69 KiB) Viewed 7208 times

And since it was already set to use 1MB, I disabled Spartados X, changed to Stock XL and went ahead and saved the settings by pressing 'S', then booted by pressing 'Q'.

I had Configured my SIO2SD to boot with the Numen demo, which requires 320KB RAM, which I am happy to say booted and ran perfectly:

Numen1.jpg (81.75 KiB) Viewed 7208 times

Numen2.jpg (71.6 KiB) Viewed 7208 times

Overall a very nice upgrade for my 800XL, which will give me all sorts of options to play with, since it also allows for flashable cartridge slots. I just need to learn how to drive it now

[redhawk668]

I have used the modulator as a base, I used double sided tacky tape to mount it on the modulator. Works nicely and the tacky tape works perfect as isolation. Together with the Sophia RGB upgrade, it all fits nicely in the small case. I had to modify the case a little bit to mount the RGB output for the Sophia RGB upgrade.