William wrote:
The 6502 is only capable of addressing 64kb of RAM, so you have to do page swapping to use more. The 65816 can address natively 16mb with it's 24 address lines. Most IIe programs weree small enough to fix in the limited amount of ram, and attempt to implement page swapping.
It's worth clarifying that AUX RAM cards operate by *bank switching*, not "swapping". Bank switching alters the physical RAM addressed in a large or small region of the processor's address space, and does so in a single instruction time, while "swapping" implies copying--often to a backing store--and is much slower. The "Slinky" slot RAM cards generally *do* require copying, since their RAM is not directly addressable. -michael NadaNet 3.0 for Apple II parallel computing! Home page: http://home.comcast.net/~mjmahon/ "The wastebasket is our most important design tool--and it's seriously underused."