Figure 6.1:
Essential elements of a personal computer
the mother board: CPU, RAM, BIOS, some I/O & timing circuits
the I/O bus: expansion cards
Note: CPU often has a separate, faster & wider bus to access
memory (RAM)
I/O card and the connection to the outside world
operation of the computer boils down to controlled transfer and
manipulation of bits (digital on/off, 0V/5V levels) among various
components
complex operations: many clock cycles; some devices may have to
wait; computer is not a ``real-time'' device! -- but
latency is small
structure of a computer bus:
address lines -- which device is getting/sending data;
auxiliary -- the timing of the transfer, handshaking;
data lines AD0-AD7 -- the data may be a real number,
a machine instruction, a part of an address, etc.