Problem – Multiply two 8 bit numbers stored at address 2050 and 2051. Result is stored at address 3050 and 3051. Starting address of program is taken as 2000.
- We are taking adding the number 43 seven(7) times in this example.
- As the multiplication of two 8 bit numbers can be maximum of 16 bits so we need register pair to store the result.
|2000||LHLD 2050||H←2051, L←2050|
|2004||MOV C, D||C←D|
|2005||MVI D 00||D←00|
|2007||LXI H 0000||H←00, L←00|
|200C||JNZ 200A||If Zero Flag=0, goto 200A|
|200F||SHLD 3050||H→3051, L→3050|
Explanation – Registers used: A, H, L, C, D, E
- LHLD 2050 loads content of 2051 in H and content of 2050 in L
- XCHG exchanges contents of H with D and contents of L with E
- MOV C, D copies content of D in C
- MVI D 00 assigns 00 to D
- LXI H 0000 assigns 00 to H and 00 to L
- DAD D adds HL and DE and assigns the result to HL
- DCR C decreaments C by 1
- JNZ 200A jumps program counter to 200A if zero flag = 0
- SHLD stores value of H at memory location 3051 and L at 3050
- HLT stops executing the program and halts any further execution