Instruction Set Descriptions, C-30 | Intel 80C186XL, 80C188XL

INSTRUCTION SET DESCRIPTIONS

Table C-4. Instruction Set (Continued)

Name	Description	Operation	Flags
Name	Description	Operation	Affected
			Affected

MOVS	Move String:	(dest-string) ← (src-string)	AF –
	MOVS dest-string, src-string		CF –
	MOVS dest-string, src-string		DF –
	Transfers a byte or a word from the		DF –
	Transfers a byte or a word from the		IF –
	source string (addressed by SI) to the		IF –
	source string (addressed by SI) to the		OF –
	destination string (addressed by DI)		OF –
	destination string (addressed by DI)		PF –
	and updates SI and DI to point to the		PF –
	and updates SI and DI to point to the		SF –
	next string element. When used in		SF –
	next string element. When used in		TF –
	conjunction with REP, MOVS		TF –
	conjunction with REP, MOVS		ZF –
	performs a memory-to-memory block		ZF –
	performs a memory-to-memory block
	transfer.
	Instruction Operands:
	MOVS dest-string, src-string
	MOVS (repeat) dest-string, src-string

MUL	Multiply:	When Source Operand is a Byte:	AF ?
	MUL src	(AX) ← (AL) × (src)	CF
	MUL src	(AX) ← (AL) × (src)	DF –
	Performs an unsigned multiplication of	if	DF –
		if	IF –
		(AH) = 0
	the source operand and the accumu-
			OF ¸
		then	OF ¸
	lator. If the source is a byte, then it is	(CF) ← 0	PF ?
	multiplied by register AL, and the		PF ?
			SF ?
		else
	double-length result is returned in AH
			TF –
		(CF) ← 1
	and AL. If the source operand is a
			ZF ?
		(OF) ← (CF)
	word, then it is multiplied by register


	AX, and the double-length result is	When Source Operand is a Word:
	returned in registers DX and AX. The	(DX:AX) ← (AX) × (src)
	operands are treated as unsigned	(DX:AX) ← (AX) × (src)
	operands are treated as unsigned	if
	binary numbers (see AAM). If the	if
	binary numbers (see AAM). If the	(DX) = 0
	upper half of the result (AH for byte	(DX) = 0
	upper half of the result (AH for byte	then
	source, DX for word source) is non-	then
	source, DX for word source) is non-	(CF) ← 0
	zero, CF and OF are set; otherwise	(CF) ← 0
	zero, CF and OF are set; otherwise	else
	they are cleared.	else
	they are cleared.	(CF) ← 1
		(CF) ← 1
	Instruction Operands:	(OF) ← (CF)
	MUL reg
	MUL mem

NOTE: The three symbols used in the Flags Affected column are defined as follows:

–the contents of the flag remain unchanged after the instruction is executed ¸? the contents of the flag is undefined after the instruction is executed

the flag is updated after the instruction is executed

Intel 80C186XL, 80C188XL Instruction Set Descriptions, Table C-4.Instruction Set Continued, C-30

Models: 80C186XL 80C188XL

MOVS dest-string, src-string

C-30