Super FX Opcode Matrices

The Super FX has two prefix flags called ALT1 and ALT2 that alter the way the GSU interprets opcodes. These four opcode matrices will show which instruction actually runs depending on how those prefix flags are set.

ALT1 = 0, ALT2 = 0

	x0	x1	x2	x3	x4	x5	x6	x7	x8	x9	xA	xB	xC	xD	xE	xF
0x	STOP	NOP	CACHE	LSR	ROL	BRA	BGE	BLT	BNE	BEQ	BPL	BMI	BCC	BCS	BVC	BVS
1x	TO R0	TO R1	TO R2	TO R3	TO R4	TO R5	TO R6	TO R7	TO R8	TO R9	TO R10	TO R11	TO R12	TO R13	TO R14	TO R15
2x
3x													LOOP	ALT1	ALT2	ALT3
4x													PLOT	SWAP	COLOR	NOT
5x
6x
7x	MERGE	AND R1	AND R2	AND R3	AND R4	AND R5	AND R6	AND R7	AND R8	AND R9	AND R10	AND R11	AND R12	AND R13	AND R14	AND R15
8x
9x	SBK	LINK #1	LINK #2	LINK #3	LINK #4	SEX	ASR	ROR							LOB	FMULT
Ax	IBT R0	IBT R1	IBT R2	IBT R3	IBT R4	IBT R5	IBT R6	IBT R7	IBT R8	IBT R9	IBT R10	IBT R11	IBT R12	IBT R13	IBT R14	IBT R15
Bx	FROM R0	FROM R1	FROM R2	FROM R3	FROM R4	FROM R5	FROM R6	FROM R7	FROM R8	FROM R9	FROM R10	FROM R11	FROM R12	FROM R13	FROM R14	FROM R15
Cx	HIB
Dx																GETC
Ex																GETB
Fx

ALT1 = 0, ALT2 = 1

	x0	x1	x2	x3	x4	x5	x6	x7	x8	x9	xA	xB	xC	xD	xE	xF
0x	STOP	NOP	CACHE	LSR	ROL	BRA	BGE	BLT	BNE	BEQ	BPL	BMI	BCC	BCS	BVC	BVS
1x	TO R0	TO R1	TO R2	TO R3	TO R4	TO R5	TO R6	TO R7	TO R8	TO R9	TO R10	TO R11	TO R12	TO R13	TO R14	TO R15
2x
3x													LOOP	ALT1	ALT2	ALT3
4x													PLOT	SWAP	COLOR	NOT
5x
6x
7x	MERGE
8x
9x	SBK	LINK #1	LINK #2	LINK #3	LINK #4	SEX	ASR	ROR							LOB	FMULT
Ax	IBT R0	IBT R1	IBT R2	IBT R3	IBT R4	IBT R5	IBT R6	IBT R7	IBT R8	IBT R9	IBT R10	IBT R11	IBT R12	IBT R13	IBT R14	IBT R15
Bx	FROM R0	FROM R1	FROM R2	FROM R3	FROM R4	FROM R5	FROM R6	FROM R7	FROM R8	FROM R9	FROM R10	FROM R11	FROM R12	FROM R13	FROM R14	FROM R15
Cx	HIB	OR #1	OR #2	OR #3	OR #4	OR #5	OR #6	OR #7	OR #8	OR #9	OR #10	OR #11	OR #12	OR #13	OR #14	OR #15
Dx																RAMB
Ex																GETBL
Fx

ALT1 = 1, ALT2 = 0

	x0	x1	x2	x3	x4	x5	x6	x7	x8	x9	xA	xB	xC	xD	xE	xF
0x	STOP	NOP	CACHE	LSR	ROL	BRA	BGE	BLT	BNE	BEQ	BPL	BMI	BCC	BCS	BVC	BVS
1x	TO R0	TO R1	TO R2	TO R3	TO R4	TO R5	TO R6	TO R7	TO R8	TO R9	TO R10	TO R11	TO R12	TO R13	TO R14	TO R15
2x
3x	STB (R0)	STB (R1)	STB (R2)	STB (R3)	STB (R4)	STB (R5)	STB (R6)	STB (R7)	STB (R8)	STB (R9)	STB (R10)	STB (R11)	LOOP	ALT1	ALT2	ALT3
4x													RPIX	SWAP	CMODE	NOT
5x	ADC R0	ADC R1	ADC R2	ADC R3	ADC R4	ADC R5	ADC R6	ADC R7	ADC R8	ADC R9	ADC R10	ADC R11	ADC R12	ADC R13	ADC R14	ADC R15
6x
7x	MERGE
8x	UMULT R0	UMULT R1	UMULT R2	UMULT R3	UMULT R4	UMULT R5	UMULT R6	UMULT R7	UMULT R8	UMULT R9	UMULT R10	UMULT R11	UMULT R12	UMULT R13	UMULT R14	UMULT R15
9x	SBK	LINK #1	LINK #2	LINK #3	LINK #4	SEX	DIV2	ROR							LOB	FMULT
Ax	IBT R0	IBT R1	IBT R2	IBT R3	IBT R4	IBT R5	IBT R6	IBT R7	IBT R8	IBT R9	IBT R10	IBT R11	IBT R12	IBT R13	IBT R14	IBT R15
Bx	FROM R0	FROM R1	FROM R2	FROM R3	FROM R4	FROM R5	FROM R6	FROM R7	FROM R8	FROM R9	FROM R10	FROM R11	FROM R12	FROM R13	FROM R14	FROM R15
Cx	HIB
Dx																GETC
Ex																GETBH
Fx

ALT1 = 1, ALT2 = 1

	x0	x1	x2	x3	x4	x5	x6	x7	x8	x9	xA	xB	xC	xD	xE	xF
0x	STOP	NOP	CACHE	LSR	ROL	BRA	BGE	BLT	BNE	BEQ	BPL	BMI	BCC	BCS	BVC	BVS
1x	TO R0	TO R1	TO R2	TO R3	TO R4	TO R5	TO R6	TO R7	TO R8	TO R9	TO R10	TO R11	TO R12	TO R13	TO R14	TO R15
2x
3x													LOOP	ALT1	ALT2	ALT3
4x													PLOT ?	SWAP	COLOR ?	NOT
5x
6x
7x	MERGE	BIC #1	BIC #2	BIC #3	BIC #4	BIC #5	BIC #6	BIC #7	BIC #8	BIC #9	BIC #10	BIC #11	BIC #12	BIC #13	BIC #14	BIC #15
8x
9x	SBK	LINK #1	LINK #2	LINK #3	LINK #4	SEX	DIV2 ?	ROR							LOB	FMULT
Ax	IBT R0	IBT R1	IBT R2	IBT R3	IBT R4	IBT R5	IBT R6	IBT R7	IBT R8	IBT R9	IBT R10	IBT R11	IBT R12	IBT R13	IBT R14	IBT R15
Bx	FROM R0	FROM R1	FROM R2	FROM R3	FROM R4	FROM R5	FROM R6	FROM R7	FROM R8	FROM R9	FROM R10	FROM R11	FROM R12	FROM R13	FROM R14	FROM R15
Cx	HIB
Dx																ROMB
Ex																GETBS
Fx