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AAD -- ASCII Adjust AX before Division

Opcode    Instruction    Clocks    Description

D5 0A     AAD            19        ASCII adjust AX before division

Operation

AL := AH * 10 + AL;
AH := 0;

Description

AAD is used to prepare two unpacked BCD digits (the least-significant digit in AL, the most-significant digit in AH) for a division operation that will yield an unpacked result. This is accomplished by setting AL to AL + (10 * AH), and then setting AH to 0. AX is then equal to the binary equivalent of the original unpacked two-digit number.

Flags Affected

SF, ZF, and PF as described in Appendix C; OF, AF, and CF are undefined

Protected Mode Exceptions

None

Real Address Mode Exceptions

None

Virtual 8086 Mode Exceptions

None

up: Chapter 17 -- 80386 Instruction Set
prev: AAA ASCII Adjust after Addition
next: AAM ASCII Adjust AX after Multiply