ParanoidLittleMan, on Wed Aug 1, 2012 2:50 AM, said:
I don't know about MMU type not supporting 2MB of RAM. IMP brand supports not 2.5 MB (will see only 2 then) - that's what I expereienced. I guess that problem is somewhere else.
Ops. You can not expand from 1MB to 2MB just like that. 1MB uses both banks. Only way is to replace whole RAM with 1Mb chips (instead 256Kb ones). It may be done by leaving original chips in board, but deactivationg them by connecting all CAS/RAS/WR lines to high. And adding board with 2MB RAM - but max 16 chips total. I have one.
Considering IDE for 1040/520 ST: http://atari.8bitchip.info/aidesch.htm
Thanks for the link and info.
I removed the original chips completely , as instructed by the hack way back then, and no longer have them to put back....and ran lines to the new sticks...When I boot the system up now, only 1meg is seen...I know it might be something to do with the MMU chip, being only able to register the 1 meg...as this has stayed in my head, as being told on a forum back then...if it does not see the 2megs then you have to swap out the MMU for a newer one that registers 2meg and above.
Now as I believe if my soldering was bad, on one stick or the other, the system would not recognize any....So as it is seeing 1 meg, I know my work so far is sound...or am i decieved in believing that?