Command: AAA - ASCII Adjust After Addition
Arguments: none
Usage: AAA
Effects: AAA should be used after a one-byte ADD instruction whose destination was the AL register: by means of examining the value in the low nibble of AL and also the auxiliary carry flag AF, it determines whether the addition has overflowed, and adjusts it (and sets the carry flag) if so. You can add long BCD strings together by doing ADD/AAA on the low digits, then doing ADC/AAA on each subsequent digit.
Flags to be set: CF=1 when addition has overflowed