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Program to pack the two unpacked BCD numbers

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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
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