|Function:||Multiply Accumulator by B|
|MUL AB||0xA4||1||4||C, OV|
Description: Multiples the unsigned value of the Accumulator by the unsigned value of
the "B" register. The least significant byte of the result is placed in the Accumulator and
the most-significant-byte is placed in the "B" register.
The Carry Flag (C) is always cleared.
The Overflow Flag (OV) is set if the result is greater than 255 (if the most-significant
byte is not zero), otherwise it is cleared.