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Multiply Two 8-bit Numbers in 8086 Microprocessor

In this tutorial, we will learn how to multiply two 8-bit numbers in 8086 Microprocessor? By Ayush Sharma Last updated : May 22, 2023

Problem Statement

Write a program in 8086 microprocessor to multiply two 8-bits numbers, where numbers are stored from offset 500 and store the result into offset 600.

Algorithm

1. Load data from offset 500 to register AL (first number)
2. Load data from offset 501 to register BL (second number)
3. Multiply them (AX=AL*BL)
4. Store the result (content of register AX) to offset 600
5. Stop

8086 program to multiply two 8-bit numbers

ADDRESS	MNEMONICS	COMMENTS
400	MOV SI, 500	SI=500
403	MOV DI, 600	DI=600
406	MOV AL, [SI]	AL<-[SI]
408	INC SI	SI=SI+1
409	MOV BL, [SI]	BL<-[SI]
40B	MUL BL	AX=AL*BL
40D	MOV [DI], AX	AX->[DI]
40F	HLT	END

Explanation

1. MOV SI, 500 set 500 to SI
2. MOV DI, 600 set 600 to DI
3. MOV AL, [SI] load contents of offset SI to register AL
4. INC SI increase value of SI by 1
5. MOV BL, [SI] load contents of offset SI to register BL
6. MUL BL multiply contents of register AL and BL
7. MOV [DI], AX store the result (contents of register AX) to offset DI
8. HLT End.

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