8-bit CPU and Assembler

A JS implementation of the Logisim 8-bit CPU, and the reference assembler.

Assembler

#	Mnemonics	Action
0	AND Ra, Rb	Ra &= Rb
1	OR Ra, Rb	Ra |= Rb
2	ADD Ra, Rb	Ra += Rb
3	SUB Ra, Rb	Ra -= Rb
4	LW Ra, (Rb)	Ra = Mem[Rb]
5	SW Ra, (Rb)	Mem[Rb] = Ra
6	MOV Ra, Rb	Ra = Rb
7	INP Ra	Ra = Inp
8	JEQ Ra, value|label	PC = value|label, Ra == 0
9	JNE Ra, value|label	PC = value|label, Ra != 0
a	JGT Ra, value|label	PC = value|label, Ra > 0
b	JLT Ra, value|label	PC = value|label, Ra < 0
c	LW Ra, value|label	Ra = Mem[value|label]
d	SW Ra, value|label	Mem[value|label] = Ra
e	LI Ra, value|label	Ra = value|label
f	JMP value|label	PC = value|label

Registers

##	Name	Description
00	R0	User data
01	R1	User data
10	R2	User data (output pins A0-A7)
11	R3	User data (output pins B0-B7)