1. Programming Examples

2. The following listing show the same function using indirect addressing
Example 1: Write a program to store the data byte FFH in memory location 9000H
MVI A, FFH
; STORE FFH IN THE ACCUMULATOR
STA 9000H
; COPY ACCUMULATOR CONTENTS TO THE ADDRESS 9000H
HLT
; STOP PROGRAM EXECUTION
The following listing show the same function using indirect addressing
LXI H, 9000H
; LOAD HL EITH 9000H
MVI A, FFH
; STORE FFH IN THE ACCUMULATOR
MOV M,A
; STORE FFH IN MEMORY LOCATION POINTED BY THE HL REGISTER PAIR
HLT
; STOP PROGRAM EXECUTION

3. Example 2: Write a program to exchange the contents of memory location 9000H and 9050H
LDA 9000H
;Load the contents of memory location 9000H in the accumulator
MOV C,A
; Move the contents of the accumulator in register C
LDA 9050H
;Load the contents of memory location 9050H in the accumulator
STA 9000H
; STORE THE CONTENTS OF THE ACCUMULATOR IN MEMORY ADDRESS 9000H
MOV A,C
; Move the saved contents in register C back to the accumulator
STA 9050H
; Store the contents of the accumulator in 9050H
HLT
; STOP PROGRAM EXECUTION

4. The following listing show the same function using indirect addressing
LXI H, 9000H
;Load the first address 9000H in the HL register pair
LXI D, 9050H
;Load the second address 9050H in the DE register pair
MOV C, M
;Move the contents of memory location 9000H to register C
LDAX D
; Move the contents of memory location 9050H to the accumulator
MOV M, A
; Store the contents of the accumulator in memory location 9000H
MOV A, C
; Move the contents of register C to the accumulator
STAX D
; Store the contents of the accumulator in memory location 9050H
HLT
; STOP PROGRAM EXECUTION

5. Example 3: Write a program to add the values presented in memory locations 9000H and 9001H, then store the results in memory location 9002H
LXI H, 9000H
;Load the first address 9000H in HL
MOV A, M
; Load the first operand in the accumulator
INX H
;Increment HL by 1 so it will point to the second memory location
ADD M
; Add the contents of the memory location to the accumulator
; Increment HL
MOV M, A
; Store the contents of the accumulator in 9002H
HLT
; STOP PROGRAM EXECUTION

6. Example 4: Write a program to subtract the values presented in memory locations 9000H and 9001H, then store the results in memory location 9002H
Homework

7. Example 4: Write a program to add two 16-bit values presented in memory locations 9000H and 9001H, and 9002H and 9003H, then store the results in memory location 9004H and 9005H. Note the most significant bytes are 9001H, 9003H and 9005H
LHLD 9000H ; Load the first 16 bit value to HL
XCHG ; Save the value of HL in DE
LHLD 9002H ; Load the second 16-bit value in HL
MOV A, E ; Move the lower byte of the first value to A
ADD L ; Add the lower bytes of the two numbers
MOV L, A ; Store the result in L
MOV A, D ; Move the higher byte of the first value to A
ADC H ; Add the higher bytes with carry
MOV H, A ; store the results in H
SHLD 9004H ; store the results in memory location 9004H
HLT ; Stop the program

8. LHLD 9000H ; Load the first 16 bit value to HL
XCHG ; Save the value of HL in DE
LHLD 9002H ; Load the second 16-bit value in HL
DAD D ; Add the contents of DE to HL
SHLD 9004H ; store the results in memory location 9004H
HLT ; Stop the program