AhmadHusen said:
is it possible to create a simple computer without a microprocessor? if
yes .how?if no ,why?
The concept of the arithmetic-logic unit (ALU) is independent of
microprocessor ICs. You can make an ALU and support circuitry
(definition of a microprocessor) out of discrete transistors, vacuum
tubes, or even relays:
http://www.cs.pdx.edu/~harry/Relay/index.html
Note that the memory on the relay computer in the link is a SRAM IC,
rather than relays. That's primarily because each bit of relay memory,
like each bit of valve, transistor or IC mask memory, is boring and
repetitive, takes a lot of space, and you need an awful lot of them.
This also makes it easier to load a program.
As to why, you would have to ask yourself. There's no real world
advantage in doing it in any of the above ways.
I would guess the relay computer above was done as a teaching tool to
show that the ALU concept is independent of an IC process. Things have
come a long way since ENIAC. If you want to play, get a development
system for a PIC, and have fun. There's a lot more rewarding stuff to
do than reinvent the wheel.
Good luck
Chris
