The 8051 Microcontroller and Embedded

Department of Computer Scien

ce and Information Engineering

National Cheng Kung University, TAIWAN

HANEL

SERIAL COMMUNI-CATION INTERRUPTUse of Serial COM in 8051(cont’)

...;-----------------SERIAL PORT ISR

ORG 100H

SERIAL: JB TI,TRANS;jump if TI is high

MOV A,SBUF ;otherwise due to receiveMOV P0,A ;send incoming data to P0CLR RI ;clear

RI since CPU doesn’t

RETI ;return from ISR

TRANS: CLR TI ;c

lear TI since CPU doesn’t

RETI ;return from ISREND