#More on BAD CHIP RAM
25-Nov-90 19:45:32
Sb: #7044-#More on BAD CHIP RAM
Fm: Gregory B. Tibbs 73767,456
To: Don Curtis/SYSOP 76703,4321
Nope. Think about it. Most of those A1000 memory boards fit into the CPU
socket and not anywhere near the custom chip bus. CBM just decoded the
extra 512K at C00000H in the A500 and A2000. The ROM checks for chip
registers or RAM. If it finds ram at c00000H, it adds it to the system
list. Therefore no autoconfig registers are needed. It also gave priority
to that ram, which is why the 512Kfast/512K chip A2000s and A500s were
slower than the A1000 by a few percent. It was an easy way to get the 1 meg
machine's extra 512K recognized. There is no manditory tie-in to the chip
ram bus.
-Greg