Install U1MB in 16KB 600XL?

[Calab]

From what I'm told, you need to upgrade to 64K in the 600XL before you install an U1MB. Do you actually need to install the RAM, or just perform the jumper updates?

 

I have the 600XL, and the U1MB, but no 64K chips.

Is there a preferred method to update the 16K 600XL to accept an U1MB?

[+mytek]

You need 64K of base RAM, so yes you will have to do the full upgrade, jumpers and new DRAM.

 

[Beeblebrox]

 

[Dinadan67]

5 hours ago, Calab said:

Is there a preferred method to update the 16K 600XL to accept an U1MB?

The easiest way is probably this little board from Lotharek: klick

Edited May 18, 2022 by Dinadan67

[flashjazzcat]

These two videos may be of interest:

 

 

 

[bfollowell]

5 hours ago, Dinadan67 said:

The easiest way is probably this little board from Lotharek: klick

 

I second this. I've done this on two of my 8-bits and a 600XL that I upgraded for a fellow AA member. The old mods are easy enough to perform and chips are still readily available, but I thought the SRAM may prove more reliable in the long-run and will definitely use less power and run a little cooler. I'll probably get around to installing the SRAM upgrade in all of my 8-bits eventually. It replaces other parts of the memory & delay line circuits as well, not just the original RAM.

 

[Nermal]

 

I've recently got a 600XL from Ebay.   The guy I bought it off was very knowledgeable, it had already been updated to 64K (With Tosh Ram I think) 

 

He told me about the U1MB &  Side3 Combo so I treated myself to it and a sDriveMax.

 

I couldn't fit the U1MB into the case and the thought of drilling holes into the mainboard left me in a cold sweat so hacked the sdrive Max case from Thingiverse into a reasonable add on.

 

The final beastie.

 

The Side3 and U1MB combo is so good just soooo many options just really getting to grips with it.

 

 

 

 

Love that the SDrive can emulate tapes, something about the "beeeeeeeeep, beeeeeeeep, beeeeeeeeep,  BOOT ERROR, farty noise" that is pure nostalgia from my 400 days. 

 

[Beeblebrox]

3 hours ago, bfollowell said:

 

I second this. I've done this on two of my 8-bits and a 600XL that I upgraded for a fellow AA member. The old mods are easy enough to perform and chips are still readily available, but I thought the SRAM may prove more reliable in the long-run and will definitely use less power and run a little cooler. I'll probably get around to installing the SRAM upgrade in all of my 8-bits eventually. It replaces other parts of the memory & delay line circuits as well, not just the original RAM.

 

@bfollowell Just a few observations.

 

The SDRAM module is certainly a good alternative option and has some great specs:

 

• replaces base ram of 64KB in all 8bit ATARI
• replaces broken DELAY LINE chip in XL computers and many more ICs - refer to schematics down the page
• upgrades ram in 600XL to 64KB
• PCB thickness is 0,8mm
• Ultimate 1MB connector
• VBXE IRQ connector
• CRUCIAL for RAPIDUS installation ...in major cases :-) (2022-02-10)

For the 600XL I've generally always gone for the old school method using 2 x DRAM replacements because as you say it's relatively quick to install and the RAM chips are relatively low cost also. (It takes around 20mins to upgrade it once you are familiar with what to do). 

I can get the SDRAM module for around £27 incl postage costs here in the UK so for me when it comes to the U1MB upgrade the old school 64K upgrade way is the cheapest.

 

The SRAM option, (as per specs above), is also obviously needed for the Rapidus upgrade and doubles as a Delay line chip replacement, etc in XLs. For 600XL as a method of upgrading from 16K to 64K it looks like minimal soldering is required for the install. For 800XLs (where you are replacing the existing 64K ram), it looks like a lot more work is involved as you either have to remove all the old ram if it's running hot, or remove all the resistors on the datalines for the ram chips if the chips aren't hot. Aside the little extra cost I would incur in buying the SRAM module, I think I also discounted it because of the latter work needed.

 

Great to have both methods though.

 

 

 

 

[cwilbar]

10 hours ago, Dinadan67 said:

The easiest way is probably this little board from Lotharek: klick

This is a great little board.  That was how I upgraded my first 600XL.... then I pulled it and did the chip upgrade via trace work/etc so that the 4464s can be removed and replaced if memory was an issue.... all so that it was like a genuine 64K 600XL (if there had ever been such a thing).

 

that board is probably the least amount of work of an internal RAM upgrade.

 

[Calab]

12 hours ago, Dinadan67 said:

The easiest way is probably this little board from Lotharek: klick

That looks like just what I need... but $26 shipping for a $20 part isn't fun, and I don't need anything else that Lotharek has. 

[Calab]

5 hours ago, Nermal said:

I couldn't fit the U1MB into the case and the thought of drilling holes into the mainboard left me in a cold sweat so hacked the sdrive Max case from Thingiverse into a reasonable add on.

The U1MB fits OK into the 600XL by using one of the holes holding the SIO port into place. The shield won't go back on afterward, of course, but you don't need to drill anything. I will post pictures when I do my installation.

 

[bfollowell]

1 hour ago, Calab said:

That looks like just what I need... but $26 shipping for a $20 part isn't fun, and I don't need anything else that Lotharek has. 

Check with Gavin at Vintage Computer Center or Marlin at The Brewing Academy. They both stock these occasionally, though I don't know what their stock levels look like at the moment.

 

[cwilbar]

On 5/18/2022 at 11:29 AM, Nermal said:

 

 

I couldn't fit the U1MB into the case and the thought of drilling holes into the mainboard left me in a cold sweat so hacked the sdrive Max case from Thingiverse into a reasonable add on.

 

 

 

I mounted U1MB inside my 600XL.  I didn't want to drill on the mainboard, so I used some sort of vinyl? plastic drip edging scrap I had around, and cut it into a L shape.  I used acetone to bond that to the back right inside of the 600XL, and I mounted the U1MB onto that with 2 screws.  If I ever want to put it back to stock, I should be able to remove the L shaped plastic from the case and it should leave a minimal blemish on the plastic, but no holes drilled.

 

I like the form factor of the 600XL.  I did a UAV video upgrade in mine, and removed the channel switch and installed the 5 pin DIN.

 

 

[Beeblebrox]

If you don;t mind drilling just one small hole then installing the U1MB inside the 600XL I've found is pretty straightforward. I drilled just the one hole right of the PBI and shortened the mounting post that comes with the U1MB by approx 7mm. I also removed the ribbon cable retaining clips on both ribbons when plugged into the U1MB. That provided enough clearance. This lowering of the profile height of the U1MB means it allows the top casing and keyboard to clear it without any issues once closed up. I've done this in two 600XL U1MB installs.

 

Pass the bolt through from the underside of the 600XL's PCB - with a plastic washer or improvised plastic barrier as in the pic - then the nylon plastic mounting post, and the first nut. Then pop on the U1MB and secure it loosely at first with the 2nd nut.

 

The U1MB PCB sits comfortably flat over the OS ROM socket with the Harting ribbon cable plugged into the latter and the OS Rom socket, and if you get the height of the mounting post right it sits on top of the ribbon cable itself - thus makes sure nothing on the underside gets shorted - and it supports the U1MB in situ at the same time. (That's why I don't drill a 2nd hole in the 600XL's PCB or use a 2nd mounting post - it's not needed given the board rests as it does).

 

A few pics:

 

     

 

         

 

 

       

[Calab]

1 hour ago, Beeblebrox said:

If you don;t mind drilling just one small hole then installing the U1MB inside the 600XL I've found is pretty straightforward.

Actually, it's even easier than that.  Just push the plastic rivet out on the SIO connector and use that hole to mount the U1MB!

 

[Nermal]

Thanks guys!    Will have another look, will look better than my Heath Robinson add on  .

 

 

[+mytek]

In that same approximate mounting location I found that with some creative bending of the ribbon cables, the installation can look quite professional.

 

 

No need to shorten the cables, I just tucked the excess underneath the U1MB.

 

[+Larry]

@mytek

Interesting CF adapter!  Is that one long board or two?  And is there more information about it? And that is a really neat installation of boards!

[+mytek]

49 minutes ago, Larry said:

@mytek

Interesting CF adapter!  Is that one long board or two?  And is there more information about it? And that is a really neat installation of boards!

It is a single board with an off the shelf CF to IDE adapter board soldered on top. It was strictly a feasibility exercise, and not something ever released to the public.

 

Go here to learn more: https://ataribits.weebly.com/blog/category/monster-600xl

 

[flemingt]

You can fit a u1Mb in a 600xl no bother if you have access to a 3d printer. I designed a bracket, no drilling required.

[Calab]

21 minutes ago, flemingt said:

You can fit a u1Mb in a 600xl no bother if you have access to a 3d printer. I designed a bracket, no drilling required.

Very nice... Uploaded to Thingiverse?

 

[Beeblebrox]

22 minutes ago, flemingt said:

You can fit a u1Mb in a 600xl no bother if you have access to a 3d printer. I designed a bracket, no drilling required.

@flemingt nice job - do you have the 3D printing STL file which you might be willing to share?

[Beeblebrox]

@Calab  heh heh our replies crossed over there. 

[flemingt]

Sure thing, it's part of this project (my 600xl mechanical keyboard)

https://github.com/flemingt/project-helena