Interrupt Exception Processing Flowchart - Motorola M68060 User Manual

AUTOVECTOR #25–#31
Figure 8-4. Interrupt Exception Processing Flowchart
error occurs during the exception processing sequence for a reset, a double bus fault is gen-
erated. The processor halts and signals the double bus fault status on the processor status
outputs ([PST4–PST0] = $1C). Execution of the reset instruction does not cause a reset
exception, nor does it affect any internal registers except the PC. The execution of this
MOTOROLA
ENTRY
SAVE INTERNAL
COPY OF SR
S 1
=
T 0
=
I2–I0 LEVEL OF
=
INTERRUPT
FETCH VECTOR
FROM INTERRUPTING
DEVICE
BUS ERROR
IF NO VECTOR #
SPURIOUS INTERRUPT
VECTOR #24
VECTOR OFFSET,
PC, AND SR
STACK FRAME
CALCULATE ADDRESS
OF FIRST INSTRUCTION
OF HANDLER
FETCH FIRST
INSTRUCTION
OF HANDLER
OTHERWISE
BEGIN INSTRUCTION
EXECUTION
EXIT
M68060 USER'S MANUAL
BUS ERROR
BUS ERROR OR
ADDRESS ERROR
PROCESS
ACCESS ERROR
EXIT
Exception Processing
8-15