NEC V30MZ instruction set

Official V30MZ (80186) Instructions

AAA	AAD	AAM	AAS	ADC	ADD	AND	BOUND	CALL	CBW	CLC
CLD	CLI	CMC	CMP	CMPSB	CMPSW	CS	CWD	DAA	DAS	DEC
DIV	DS	ENTER	ES	HLT	IDIV	IMUL	IN	INC	INSB	INSW
INT	INTO	IRET	JA	JBE	JC	JCXZ	JG	JGE	JL	JLE
JMP	JNC	JNO	JNP	JNS	JNZ	JO	JP	JS	JZ	LAHF
LDS	LEA	LEAVE	LES	LOCK	LODSB	LODSW	LOOP	LOOPE	LOOPNE	MOV
MOVSB	MOVSW	MUL	NEG	NOP	NOT	OR	OUT	OUTSB	OUTSW	POLL
POP	POPA	POPF	PUSH	PUSHA	PUSHF	RCL	RCR	REP	REPNE	RET
RETF	ROL	ROR	SAHF	SAR	SBB	SCASB	SCASW	SHL	SHR	SS
STC	STD	STI	STOSB	STOSW	SUB	TEST	XCHG	XLAT	XOR

Official instructions by type

Type	Instructions
Memory	MOV	XCHG	XLAT	LEA	LDS	LES	IN	OUT
Ports	IN	OUT	INSB	OUTSB	INSW	OUTSW
Arithmetic	ADD	SUB	ADC	SBB	INC	DEC	MUL	DIV	IMUL	IDIV	CMP	NEG
Numeric	CBW	CWD	AAA	AAS	AAM	AAD	DAA	DAS
Shift	ROL	ROR	RCL	RCR	SHL	SHR	SAR
Bitwise	AND	OR	XOR	NOT	TEST
Branch	JC	JNC	JZ	JNZ	JBE	JA	JO	JNO	JP	JNP	JS	JNS	JL	JGE	JLE	JG
Jump	JMP	CALL	RET	RETF
Loop	LOOP	LOOPE	LOOPNE
Interrupt	INT	IRET	INTO	HLT	BOUND
Stack	PUSH	POP	PUSHA	POPA	PUSHF	POPF
Flags	CLC	STC	CLD	STD	CLI	STI	CMC	LAHF	SAHF
Prefix	CS	DS	ES	SS
String	REP	REPE	REPNE	MOVSB	MOVSW	LODSB	STOSB	LODSW	STOSW	CMPSB	SCASB	CMPSW	SCASW
Other	NOP	ENTER	LEAVE	LOCK	POLL

Instruction encoding

ModR/M byte

The ModR/M byte is used in most addressing modes which reference a memory location. This byte consists of three bitfield values:

• oo - Mode;
• rrr - Two possible functions:
  • Register (for addressing modes which require both a register and a register/memory operand),
  • Opcode extension (for some opcodes' addressing modes which do not have such a requirement);
• mmm - Register/Memory.

The Mode and Register/Memory bitfields can refer to a memory location with an optional signed 8-bit (disp8) or 16-bit (disp16) displacement or to a register, as shown in the table below. In some addressing modes, the Register field also refers to a register; it is always interpreted as if Mode was equal to 11.

R/M \ Mode	00	01	10	11 (byte)	11 (word)
000	DS:[BX + SI]	DS:[BX + SI + disp8]	DS:[BX + SI + disp16]	AL	AX
001	DS:[BX + DI]	DS:[BX + DI + disp8]	DS:[BX + DI + disp16]	CL	CX
010	SS:[BP + SI]	SS:[BP + SI + disp8]	SS:[BP + SI + disp16]	DL	DX
011	SS:[BP + DI]	SS:[BP + DI + disp8]	SS:[BP + DI + disp16]	BL	BX
100	DS:[SI]	DS:[SI + disp8]	DS:[SI + disp16]	AH	SP
101	DS:[DI]	DS:[DI + disp8]	DS:[DI + disp16]	CH	BP
110	DS:[disp16]	SS:[BP + disp8]	SS:[BP + disp16]	DH	SI
111	DS:[BX]	DS:[BX + disp8]	DS:[BX + disp16]	BH	DI

Note that (oo = 00, mmm = 110) is a special case.

The instruction encoding lists below refer to this byte as oorrrmmm (binary), /r (hexadecimal) or /0 (hexademical, rrr used as function 0).

Official instructions

---

---

---

---

---

ADD

Instruction	Opcode (hex)	Opcode (bin)	Bytes	Cycles
ADD AL, imm	04 ii	00000100 iiiiiiii	2	1
ADD AX, imm	05 ii ii	00000101 iiiiiiii iiiiiiii	3	1
ADD mem8, imm8	80 /0 ii	10000000 oo000mmm iiiiiiii	3+	3
ADD mem16, imm16	81 /0 ii ii	10000001 oo000mmm iiiiiiii iiiiiiii	4+	3
ADD mem16, simm8	83 /0 ii ii	10000011 oo000mmm iiiiiiii iiiiiiii	4+	3
ADD mem8, reg8	00 /r	00000000 oorrrmmm	2+	3
ADD mem16, reg16	01 /r	00000001 oorrrmmm	2+	3
ADD reg8, imm8	80 /0 ii	10000000 11000mmm iiiiiiii	3+	1
ADD reg16, imm16	81 /0 ii ii	10000001 11000mmm iiiiiiii iiiiiiii	4+	1
ADD reg16, simm8	83 /0 ii ii	10000011 11000mmm iiiiiiii iiiiiiii	4+	1
ADD reg8, mem8	02 /r	00000010 oorrrmmm	2+	2
ADD reg16, mem16	03 /r	00000011 oorrrmmm	2+	2
ADD reg8, reg8	00 /r	000000.0 11rrrmmm	2	1
ADD reg16, reg16	01 /r	000000.1 11rrrmmm	2	1

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---