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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)