4 4 rite a program to perform the following using a 4pts a C

#4

4. rite a program to perform the following using a. (4pts) a. Clear the content of data memory starting at 0x80 to 0x100. b. d AB to the contents of file register starting at 0x80 to 0x100.

Solution

a )    CLR A; the content in ACC is used to clear RAM locations

       MOV R1, #80H; R1 is a pointer starting from 80H

       MOV R7, #20; 20 iterations

Again: MOV @R1, A; loop

        INC R1

        DJNZ R7, Again

b)LXI H, 4000H :HL Points 4000H

MOV A, M :Get first operand

INX H :HL Points 4001H

ADD M :Add second operand

INX H :HL Points 80H

MOV M, A :Store the lower byte of result at 80H

MVIA, 00 :Initialize higher byte result with 00H

ADC A :Add carry in the high byte result

INX H :HL Points 80H

MOV M, A :Store the higher byte of result at 80H

HLT :Terminate program execution