[<<Previous Entry]
[^^Up^^]
[Next Entry>>]
[Menu]
[About The Guide]
AAA ASCII Adjust after Addition Flags: O D I T S Z A P C
? ? ? * ? *
AAA
Logic: If (AL & 0Fh) > 9 or (AF = 1) then
AL . AL + 6
AH . AH + 1
AF . 1; CF . 1
else
AF . 0; CF . 0
AL . AL & 0Fh
Converts the number in the lower 4 bits (nibble) of AL to an unpacked
BCD number (high-order nibble of AL is zeroed).
--------------------------------------------------------------------------
Operands Clocks Transfers Bytes Example
no operands 4 - 1 AAA
--------------------------------------------------------------------------
If the lower 4 bits of the number in AL is greater than 9, or the
auxiliary carry flag is set, this instruction converts AL to its
unpacked BCD form by adding 6 (subtracting 10) to AL; adding 1 to AH;
and setting the auxiliary flag and carry flags. This instruction will
always leave 0 in the upper nibble of AL.
Note: Unpacked BCD stores one digit per byte; AH contains
the most-significant digit and AL the least-
significant digit.
See Also:
AAD
AAS
AAM
ADC
DAA
Flags
This page created by ng2html v1.05, the Norton guide to HTML conversion utility.
Written by Dave Pearson