Texas Instruments MSC1210 - Manual (Page 302)

8052 Instruction Set
E-18
MUL Multiply Accumulator by B
Syntax MUL AB
Instructions OpCode Bytes Cycles Flags
MUL AB 0xA4 1 4 C, OV
MUL multiplies the unsigned value in the accumulator by the unsigned value
in the B register. The least-significant byte of the result is placed in the accumu-
lator and the most-significant byte is placed in the B register.
The carry (C) flag is always cleared.
The overflow (OV) flag is set if the result is greater than 255 (if the
most-significant byte is not zero). Otherwise, it is cleared.
See also: DIV
NOP No Operation
Syntax NOP
Instructions OpCode Bytes Cycles Flags
NOP 0x00 1 1 None
NOP, as its name suggests, causes no operation to take place for one machine
cycle. NOP is generally used only for timing purposes. Absolutely no flags or
registers are affected.