Thanks! Do you know if such a switch setup will work if I have a megachip installed on this a500? Currently, I do, so there are really 2 megs of chip in there.
I don't, never tried it, but it doesn't hurt to try. You could even use a 3PDT switch, with the 3rd pole for the megachip wire to Gary.
DPDT = 1P [1T | 2T] + 2P [1T | 2T] + 3P [1T | 2T]
1P = pin 2 of JP2 then 1T = pin1 of JP2 and 2T = pin3 of JP2
2P = pin 2 of JP7A then 1T = pin1 of JP7A and 2T = unconnected
3P = wire from Megachip then 1T = unconnected and 2T = Gary pin36
This way, the 1P1T + 2P1T + 3P1T setting would supposedly enable 512 chip + 512 ranger (with the remaining 1 MB ignored)
and the 1P2T + 2P2T + 3P2T setting would enable the full 2 MB chip RAM.