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MUL
AB
Function:
Multiply
Description:
MUL AB multiplies the unsigned eight-bit integers in the accumulator and register
B. The low-order byte of the sixteen-bit product is left in the accumulator, and the
high-order byte in B. If the product is greater than 255 (0FF H ) the overflow flag is
set; otherwise it is cleared. The carry flag is always cleared.
Example:
Originally the accumulator holds the value 80 (50 H ). Register B holds the value 160
(0A0 H ). The instruction
MUL
will give the product 12,800 (3200 H ), so B is changed to 32 H (00110010B) and the
accumulator is cleared. The overflow flag is set, carry is cleared.
Operation:
MUL
(A7-0)
(B15-8)
Encoding:
1 0 1 0
Bytes:
1
Cycles:
4
Semiconductor Group
AB
← (A) x (B)
0 1 0 0
*
184
Instruction Set
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