Microcontroller User's Manual

23-34 MCF5282 User’s Manual MOTOROLA
Operation
Figure 23-26. UART Mode Programming Flowchart (Sheet 4 of 5)
WAS
IRQ
CAUSED
BY BEGINNING
OF A BREAK
?
SIRQ
ABRKI
N
CLEAR CHANGE-IN-
BREAK STATUS BIT
ABRKI1
N
HAS
END-OF-BREAK
IRQ
ARRIVED
YET
?
Y
Y
CLEAR CHANGE-IN-
BREAK STATUS BIT
REMOVE BREAK
CHARACTER FROM
RECEIVER FIFO
REPLACE RETURN
ADDRESS ON SYSTEM
STACK AND MONITOR
WARM START ADDRESS
SIRQR
RTE
N
Y
DOES
CHANNEL A
RECEIVER HAVE A
CHARACTER
?
INCH
PLACE CHARACTER
IN D0
RETURN