Working CPU with eight 8-bit registers and eleven commands. Instructions in the project, command list below.
LDA r - loads value from register r into accumulator
STA r - stores accumulator value in register r
CLR r - clears register r
INC r - increments the value of register r and replaces into r
DEC r - decrements the value of register r and replaces into r
COM r - stores the complement of the value in register r in the accumulator
ADD r - adds value in register r to the accumulator
SUB r - subtracts accumulator value from value in register r, replaces into accumulator
AND r - stores value of (accumulator AND r) in accumulator
IOR r - stores value of (accumulator OR r) in accumulator [inclusive or]
XOR r - stores value of (accumulator XOR r) in accumulator [exclusive or]
*Eight 8-bit registers: r must be a value between 0 and 7 and refers to the address of the register, not its contents*
Yet Another Ben Eater Inspired Simple As Possible System
I'm following along with the excellent YouTube instructional series Building an 8-bit breadboard computer! by Ben Eater.
Note that he credits the book "Digital Computer Electronics" by Albert Paul Mauvino for many of the SAP (Simple As Possible) ideas.
I'm mostly keeping it the same as his computer except: