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Program to subtract two 8 bit numbers

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Statement: Subtract the contents of memory location 2001H from the contents of memory location 2000H and store the result in memory location 2002H.

Example: 
(2000H) = 51H
(2001H) = 19H
(2002H) = 51H - 19H = 38H

Program:

LXI H, 2000H              ; HL points the location 2000H
MOV A, M                   ; Move the contents of 2000H into accumulator
INX H                           ; HL points the location 2001H
SUB M                          ; Subtract second operand from the contents of accumulator
INX H                           ; HL points the location 2002H
MOV M, A                    ; Store the result at location 2002H
HLT                              ; Terminate program execution
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