Mult Multiply (Unsigned) - Samsung S3C80A5B User Manual

S3C80A5B
MULT
— Multiply (Unsigned)
MULT dst,src
dst ← dst × src
Operation:
The 8-bit destination operand (even 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.
C: Set if result is > 255; cleared otherwise.
Flags:
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:
opc
Examples: Given: Register 00H = 20H, register 01H = 03H, register 02H = 09H, register 03H = 06H:
MULT
MULT
MULT
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.
src dst
→
00H, 02H Register 00H = 01H, register 01H = 20H, register 02H = 09H
→
00H, @01H Register 00H = 00H, register 01H = 0C0H
→
00H, #30H Register 00H = 06H, register 01H = 00H
Bytes Cycles Opcode
3 22
22
22
INSTRUCTION SET
Addr Mode
(Hex) dst src
84 RR R
85 RR IR
86 RR IM
6-59