ZiLOG Z80 User Manual page 53

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LD HL, DATA ;STARTING ADDRESS OF DATA STRING
LD DE, BUFFER;STARTING ADDRESS OF TARGET BUFFER
LD BC, 132 ;MAXIMUM STRING LENGTH
LD A, '$' ;STRING DELIMITER CODE
(HL) ;COMPARE MEMORY CONTENTS WITH
;DELIMITER
JR Z, END-$ ;GO TO END IF CHARACTERS EQUAL
LDI ;MOVE CHARACTER (HL) to (DE)
;INCREMENT HL AND DE, DECREMENT BC
JP PE, LOOP ;GO TO "LOOP" IF MORE CHARACTERS
;OTHERWISE, FALL THROUGH
;NOTE: P/V FLAG IS USED
;TO INDICATE THAT REGISTER BC WAS
;DECREMENTED TO ZERO.
LD HL, DATA;ADDRESS OF FIRST BYTE
LD B, COUNT;SHIFT COUNT
XOR A ;CLEAR ACCUMULATOR
;ROTATE LEFT LOW ORDER DIGIT IN ACC
;WITH DIGITS IN (HL)
INC HL ;ADVANCE MEMORY POINTER.
DJNZ ROTAT-$ ;DECREMENT B AND GO TO ROTAT IF
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