Anyone got an XL MMU and OS rom they would be willing to sell?

[Mr Robot]

I used the U1MB from my NTSC 800XL when I made my 1088XEL and now I can't use my XL any more. I got it from Sloopy with the U1MB already installed and I never got the replaced chips. 

 

If anyone has spares they'd be willing to part with, please let me know, I'd love to get the machine working again.

 

[Paul Westphal]

I think I have some.

 

pm me.

 

paul

[+Nezgar]

I have GAL16V8's that I can program to become XL MMU's if needed.

[Marius]

I can confirm what Nezgar wrote. A GAL can be programmed to become a 100% compatible XL MMU. I have done it too in the past. Works excellent in one my 800XL's. 

 

 

 

 

[Kyle22]

On 8/31/2019 at 8:29 PM, Nezgar said:

I have GAL16V8's that I can program to become XL MMU's if needed.

A PAL16L8 works as well. (It is the original part). Not that it matters, a GAL is just fine to use.

[Guest]

On 9/1/2019 at 1:29 AM, Nezgar said:

I have GAL16V8's that I can program to become XL MMU's if needed.

can this be done in HxD?

if so, should IC type be selected as 20 pin DIP?

and how easy is it to extract the IC information from a good MMU?

[+Nezgar]

47 minutes ago, brenski said:

can this be done in HxD?

if so, should IC type be selected as 20 pin DIP?

and how easy is it to extract the IC information from a good MMU?

I don't believe an MMU can be "extracted" - it basically had to be reverse engineered so that when programmed into a PAL or GAL, it would produce the same effect as the original. The venerable TL866 supports this GAL with the available JEDEC files. The original XL/XE is credited to @bob1200xl in 1999, and the XEGS one @tf_hh posted earlier this year does not internally credit an author.

 

The source files are actually just text files you can view with notepad, etc. Here's my sources:

XL/XE: https://atariage.com/forums/topic/155863-mmu-chip-needed/?do=findComment&comment=1911484

XEGS: https://atariage.com/forums/topic/290832-atari-xe-game-system-help-with-keyboard-issue-not-the-mylar/?do=findComment&comment=4271375

 

So really, all that's missing is the original 1200XL MMU, but who would want that! ?