exxos's Atari, Amiga & retro forum

guus.assmann wrote: ↑Mon Oct 02, 2017 10:50 am I had to select a MMU to get it going. And then I would also get a picture and desktop in High-res, but with "Jailbars"

Jailbars is due to a slight clock desync between Shifter and MMU. You could try inserting some component that would delay the clock a bit.

(As exxos mentioned I'm slowly doing this same mod to a 1040STFM. This week I might get to the first test. So far RAM and ROM have been changed out for faster variants, CPU and changing the oscillator is next)

/Troed

Hello Troed,
Then I would suggest to change the display first.
Get the DE line and shifter separated.
This bit will also work with the normal clock speed.
That change, only using 2 gates of a 74ALS00 has no negative effect on anything.
But you do need it to keep a visable picture.

BR/
Guus