The 8051 Microcontroller and Embedded

Department of Computer Scien

ce and Information Engineering

National Cheng Kung University, TAIWAN

HANEL

ROTATE INSTRUCTIONAND DATA

SERIALIZATIONSerializing Data

(cont’)

Write a program to bring in a byte of data serially one bit at a time via pin P2.7 and save it in register R2. The byte comes in with the LSB first.Solution:

MOV R5,#8

AGAIN: MOV C,P2.7 ;bring in bit

RRC ADJNZ R5,HEREMOV R2,A ;save itP2.7

CY

Register A

D7

D0

Pin