S3C84E5/C84E9/P84E9

INSTRUCTION SET

 

 

MULT — Multiply (Unsigned)

MULT dst,src

Operation: dst dst × src

The 8-bit destination operand (the even numbered register of the register pair) is multiplied by the source operand (8 bits) and the product (16 bits) is stored in the register pair specified by the destination address. Both operands are treated as unsigned integers.

Flags:

C: Set if the result is > 255; cleared otherwise.

 

Z: Set if the result is "0"; cleared otherwise.

 

S: Set if MSB of the result is a "1"; cleared otherwise.

 

V:

Cleared.

 

D:

Unaffected.

 

H:

Unaffected.

Format:

 

 

 

 

Bytes

Cycles

Opcode

Addr Mode

 

 

(Hex)

dst

src

opc

src

dst

3

22

84

RR

R

 

22

85

RR

IR

 

22

86

RR

IM

Examples:

Given:

Register 00H =

20H, register 01H = 03H, register 02H = 09H, register 03H = 06H:

 

MULT

00H, 02H

Register 00H

=

01H, register 01H

=

20H,

 

 

 

 

register 02H

=

09H

 

 

 

MULT

00H, @01H

Register 00H

=

00H, register 01H

=

0C0H

 

MULT

00H, #30H

Register 00H

=

06H, register 01H =

00H

In the first example, the statement "MULT 00H,02H" multiplies the 8-bit destination operand (in the register 00H of the register pair 00H, 01H) by the source register 02H operand (09H).

The 16-bit product, 0120H, is stored in the register pair 00H, 01H.

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Samsung S3C84E5 user manual Mult Multiply Unsigned, Mult dst,src, Operation dst ← dst × src