RealQ16s:Provisional instruction listing

This is a provisional instruction listing for the RealQ16s project.

Instructions by opcode

1 byte instructions

Range								Operation	bits								Distinct opcodes	Comment	Caveats
0000				0000				NOP	0000				0000				x1	Does nothing
0000				0001				(unused)	0000				0001				(x15 opcodes)
...								...	...
0000				1111				(Unused)	0000				1111
0001				0000				MOV r1,r2	0001				r1		r2		x12	Store r1 in r2, treating them both as 16 bit registers	r1 and r2 must be different
...								(Unused)	0001				0000				x1
								(Unused)	0001				0101				x1
								(Unused)	0001				1010				x1
0001				1111				(Unused)	0001				1111				x1
0010				0000				PUSH r1	0010				00		r1		x4	Push the 16 bit register r1
0010				0100				POP r1	0010				01		r1		x4	Pop the 16 bit register r1
0010				1000				MOV b1,r1L	0010				10		r1		x1024 (x4)	16 bit instruction 0010 10r1 vvvv vvvv - move byte b1 given by v into low byte of register r1
0010				1100				MOV b1,r1H	0010				11		r1		x1024 (x4)	16 bit instruction 0010 11r1 vvvv vvvv - move byte b1 given by v into high byte of register r1
0011				0000				MOVACO b1,r1L	0011				00		r1		x1024 (x4)	16 bit instruction 0011 00r1 vvvv vvvv - move byte b1 given by v into low byte of register r1, then clear high byte of register r1.
0011				0100
1111				1111				(two bytes prefix)	1111				1111				x256 (x1)	16 bit instruction 1111 1111 vvvv vvvv - rare instruction that have two bytes have this as their first byte.

Prefixed (rare) instructions

Prefixed with 1111 1111

Every instruction in this table has 2 bytes, the first byte is 1111 1111 and the second byte is given in the table.

Range								Operation	bits								Distinct opcodes	Comment	Caveats
0000				0000
1111				1111				(four bytes prefix)	1111				1111				x256 (x1)	16 bit instruction 1111 1111 1111 1111 vvvv vvvv - very rare instruction that have four bytes have this as their first and second bytes.

Logical instructions

These instructions are not real CPU instructions, they are allowed in assembly, and code will be generated that makes it seem as if these instructions are implemented. The listing here is alphabetical.

Unallocated instructions

• MOVACO b1,r1H - Move byte b1 into high byte of register r1, then clear low byte of register r1.