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Question 6.15: Write a program that finds the number of 1s in a given byte.

Write a program that finds the number of 1s in a given byte.

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MOV   R1,#0             ;R1 keeps number of 1s
MOV   R7,#8        ;counter, rotate 8 times
MOV   A,#97H    ;find number of 1s in 97H

AGAIN:         RLC    A                     ;rotate it thru CY

JNC    NEXT              ;check CY
INC     R1                   ;if CY=1, inc count

NEXT:           DJNZ R7,AGAIN       ;go thru 8 times

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