From Tanenbaum.
This is 1-bit ALU. Connecting N of these you can obtain a N-Bit ALU.
Component:
OUTPUT (At right top)
the lamp that is the output(0 or 1).
CONTROLLER (At left bottom)
you can see a DECODER used for controll off/on means AND.
The specific function selected give the output.
LOGIC UNIT (On top left)
input(top-down) value 0-1
INVERT A
A
ENABLE-A
B
ENABLE-B
Bolean function(INVERT A off 0):
1) AB (Logic AND) - Decoder: 00(read top-down)
2) A + B (Logic OR) - Decoder: 01(read top-down)
3) NOT B - Decoder: 10(read top-down)
Variant with INVERT A on 1
(NOT A) x B
(NOT A) + B
ADDER(At right bottom)
Decoder: 11(read top-down)
the adder with is rest lamp(on bottom) and over there there is the input of another ipotetical ALU rest.
