(i) XLAT (Translate):
This instruction is used for table lookups. It takes the value in AL (the accumulator register) as an offset into a table and replaces the value in AL with the byte at the effective address.
Example:
MOV AL, 2 ; AL contains the offset MOV BX, OFFSET Table ; BX points to the start of the table XLAT ; Replace AL with the byte at Table+2
(ii) AND (Logical AND):
This bitwise AND operation performs the logical AND between each pair of corresponding bits of the two operands. The result is stored in the destination operand.
Example:
MOV AX, 5 ; Binary: 0000 0101 AND AX, 3 ; Binary: 0000 0011 ; After AND operation, AX will be: 0000 0001 (1 in decimal)
(iii) RCR (Rotate through Carry Right):
This instruction rotates the bits in the specified operand to the right through the carry flag. The carry flag is included in the rotation.
Example:
MOV AX, 8 ; Binary: 0000 1000 RCR AX, 1 ; Rotate AX right through carry by 1 bit ; After RCR operation, AX will be: 1000 0100 (carry will be set to 0)
(iv) DAA (Decimal Adjust Accumulator):
This instruction adjusts the contents of the AL register after an addition operation in packed decimal (BCD) arithmetic.
Example:
MOV AL, 90 ; AL contains unpacked BCD (9 in tens place, 0 in units place) ADD AL, 25 ; Add 25 to AL (BCD addition) DAA ; Adjust AL to correct BCD representation ; After DAA operation, AL will be: 15 (1 in tens place, 5 in units place)
(v) AAS (ASCII Adjust for Subtraction):
This instruction adjusts the result in the AL register after a subtraction operation in ASCII-coded decimal arithmetic.
Example:
MOV AL, '7' ; AL contains ASCII representation of the digit 7 SUB AL, 3 ; Subtract 3 from AL (ASCII subtraction) AAS ; Adjust AL to correct ASCII representation ; After AAS operation, AL will be: '4' (ASCII representation of the digit 4)