CS 233 Study Guide - Midterm Guide: Apple Iie, Address Bus
Document Summary
Most devices can be considered as memories, with an address for reading or writing many isas often make this analogy explicit - to transfer data to/from a particular device, the cp;lsdkfja;sdlkjfa;lksdfj. With memory-mapped i/o, one address space is divided into two parts. For example, my old apple iie had a 16-bit address bus which could access a whole. Addresses c000-cfff in hexadecimal were not part of memory, but were used to access i/o devices. All the other addresses did reference main memory. The i/o addresses are shared by many peripherals. n the ;alsdkjfa;lksdjfa;lksdjf. To send data to a device, the cpu writes to the appropriate i/o address. The address and at a are then transmitted along the bus. Each device has to monitor the address bus to see if it is the target. The apple iie main memory ignores any transactions whose address begins with. The speaker only responds when c030 appears on the address bus.
