Datasheet

14-42 MCF5407 User’s Manual
Operation
Figure 14-39. UART Mode Programming Flowchart (Sheet 4 of 5)
WAS
IRQ CAUSED
BY BEGINNING
OF A BREAK
?
CLEAR CHANGE-IN-
BREAK STATUS BIT
HAS
END-OF-BREAK
IRQ ARRIVED
YET
?
CLEAR CHANGE-IN-
BREAK STATUS BIT
REMOVE BREAK
CHARACTER FROM
RECEIVER FIFO
REPLACE RETURN
ADDRESS ON SYSTEM
STACK AND MONITOR
WARM START ADDRESS
RTE
SIRQR
N
Y
N
DOES
CHANNEL A
RECEIVER HAVE A
CHARACTER
?
PLACE CHARACTER
IN D0
N
Y
ABRKI1
ABRKI
Y
INCH
RETURN
SIRQ