#ARTMATIC PROUNTION CODE#

Note the contents of status flags as shown in figure 8. Note that these registers can also be initialized by using the instructions:ДЇigure 7: Registers AX and CX manually initialized before the execution of instructions in example 3ДЇigure 8: Contents of AX, CX registers and status flags after the instructions in example 3 are executed In Example 3, assume the registers AX and BX are manually initialized as follows: SUB AX, 01h Subtract the hex value 01 from the value in the accumulator.SUB AX, CX Subtract value in register CX from value in accumulator.Basic formatДestination := destination вЂ“ source Example 3 The subtract instruction subtracts the source operand (second operand) from the destination operand (first operand) and the result is stored in the destination operand.

#ARTMATIC PROUNTION CODE#

Store sum in AXДЇigure 3: Status of the carry flag and registers AX, BX and CX before execution of instructions in example 2ДЇigure 4: Status of the carry flag and registers AX, BX and CX after execution of instructions in example 2ДЇigure 5: Carry flag manually set to 1 before code execution ADD AX, CX Add values in registers, AX and CX to the value in the carry flag.ADC AX, BX Add values in registers AX and BX to the value in the carry flag.ADC AX, 23h Add the hex value 23 to the value in register AX and the carry flag.It then stores the resulting value in the destination operand. The ADC instruction sums up the destination operand (first operand), the source operand (second operand) and the carry (CF) flag. Keep the sum in the address 5777ДЇigure 1: Contents of registers prior to the execution of Example 1ДЄs shown in figure 1, the content of the accumulator (register AX) was 0000h before the execution of line 1 in example 1.ДЇigure 2: Contents of accumulator after line 1 in example 1 is executed ADC ADD, 0100H Add the hex value 100 to the value at address given by 5777.ADD AX, Add the value at address 5777 to the accumulator.ADD AX, Add the value at address given by the destination index DI to the register AX.ADD AX, CX Add the values in registers CX and AX.

ADD AX, 0120H Add the hex value 120 to value in the accumulator and keep the sum in the accumulator.Basic formatДestination := destination + source Example 1

The add instruction sums up the contents of the source operand (second operand) and the destination operand (first operand) and then places the results in the source operand. Signed integers can be either positive or negative. Unsigned integers are always positive or zero. Integers used during arithmetic operations in x86 may be represented in two modes: unsigned and signed. This article will discuss only the four key operations of arithmetic instructions. The arithmetic instructions define the set of operations performed by the processor Arithmetic Logic Unit (ALU).

Artmatic prountion