icealys wrote:
Quote:
ii) address decode logic maps the address to a chip select which tells a bus device that the CPU is talking to it
I think I understand that but what sends instructions do the address decoder?
There are no instructions there, just bits of address. You can read about demultiplexer ICs (for example, 74LS138), they receive part of the address as an input and on the output only one pin is active, those with the number equal to digits on the input (i.e. if inputs equal to 000 (binary), then output0 pin will be active, if 001 - then output1 and so on).
Look, here's the second link found by google, it has some nice pictures:
http://www.ece.unm.edu/~jimp/310/slides ... mory2.html