Motorola MC68020 - Interrupt Exception Processing Flowchart

6- 16 M68020 USER’S MANUAL MOTOROLA
TEMP
S
T1, T
0
SR
1
0
➧
➧
➧
UPDATE I2–I0
➧
➧
➧
➧
– (SP)
TEMP
– (SP)
PC
– (SP)
FORMAT WORD
– (SP) OTHER EXCEPTION
DEPENDENT INFORMATION
ONCE PER INSTRUCTION
EXECUTE INTERRUPT
ACKNOWLEDGE CYCLE
AT INSTRUCTION
BOUNDARY
EXIT
M = 1
TEMP
SR
M
0
➧
➧
M = 0
PC VECTOR TABLE ENTRY
➧
PREFETCH 3 WORDS
END OF EXCEPTION PROCESSING
FOR THE INTERRUPT
BEGIN EXECUTION OF THE INTERRUPT
H
ANDLER ROUTINE OR PROCESS A
H
IGHER PRIORITY EXCEPTION
THESE
INDIVIDUA
L
BUS CYCLE
S
MAY OCCU
R
IN ANY ORDE
R
N
EGATE IPEN
D
*
OTHERWISE
I
PEND ASSERTE
D
*
Does not apply to the MC68EC020.
*
Figure 6-5. Interrupt Exception Processing Flowchart