Skip to main content

Program to pack the two unpacked BCD numbers

By

Statement: Pack the two unpacked BCD numbers stored in memory locations 2000H and 2001H and store the result in memory location 2002H. The least significant digit is stored at 2000H.

Example:

(2000H) = 04H
(2001H) = 09H
Result = (2002H) = 94H

Program:

LDA 2001H                        ; Obtain the most significant BCD digit
RLC                                    ; Rotate left 
RLC                                    ; Rotate left 
RLC                                    ; Rotate left 
RLC                                    ; Rotate left 
ANI F0H                            ; Make least significant BCD digit zero
MOV C, A                          ; Move the contents of accumulator into C register
LDA 2000H                        ; Obtain the least significant BCD digit
ADD C                                ; Add lower BCD digit
STA 2002H                         ; Store the result in 2002H
HLT                                     ; Terminate program execution
Labels:

Comments

Post a Comment

Popular posts from this blog

Program to exchange the contents of two memory locations

By
Statement: Exchange the contents of memory locations 2000H and 2001H. Example:  Initially, (2000H) = 34H (2001H) = 20H After exchanging, (2000H) = 20H (2001H) = 34H Program 1 using direct addressing instructions: LDA 2000H               ; Get the contents of location 2000H into accumulator MOV B, A                  ; Move the contents of accumulator into register B LDA 2001H                ; Get the contents of location 2001H into accumulator STA 2000H                 ; Store the contents of accumulator into location 2000H MOV A, B                  ; Move the contents of register B into accumulator STA 2001H                 ; Store the contents of accumulator into location 2001H HLT  ...
Post a Comment
Read more

Stack Operations Instructions (Part-II) - SPHL and XTHL

By
SPHL: This instruction copies the contents of HL register pair to the stack pointer (SP). It means that the stack pointer will now point to the memory location whose address was given in the HL register pair. No flags are affected. It is a one byte instruction. Register addressing mode is used. Example: If HL = 2030H, then SPHL ; This instruction will copy 2030H into SP. So SP will point to the memory location 2030H. XTHL: This instruction exchanges the contents of the memory location pointed by stack pointer with the contents of the L register and the contents of the next memory location with the contents of H register. This instruction does not alter the contents of the stack pointer. No flags are affected. It is a one byte instruction. Register Indirect addressing mode is used. Example: If HL = 5601H, SP = 2000H, (2000H) = 30H and (2001H) = 20H, then XTHL ; This instruction will exchange the contents of the memory location 2000H i.e. 3...
Post a Comment
Read more