user manual

RESET PROCESSING STATE
MOTOROLA PROCESSING STATES 7 - 35
REPEAT m
TIMES
n6
n4
n4
n4
•
•
•
n2
n1
REP m
ii1
MAIN
PROGRAM
FETCHES
n2
ii2
n3
n4
n5
n6
INTERRUPT
REJECTED
•
n7
n8
n9
INTERRUPT
PENDING
INTERRUPT
REJECTED
INTERRUPT
REJECTED
REP m
REP m
INTERRUPT
PENDING
INTERRUPT
PENDING
INTERRUPT
PENDING
n6
•
•
n2
n2
n6
•
•
•
REPEAT m TIMES
(a) Instruction Fetches from Memory
INTERRUPT CONTROL CYCLE 1 i i
INTERRUPT CONTROL CYCLE 2 i% i
FETCH REP n2 REP n4 REP n6 n7 n8 ii1 ii2 n9
DECODE REP NOP n2 n2 n2 REP NOP n4 n4 n4 REP NOP n6 n6 n6 n7 n8 ii1 ii2 n9
EXECUTE REP NOP n2 n2 n2 REP NOP n4 n4 n4 REP NOP n6 n6 n6 n7 n8 ii1 ii2 n9
INSTRUCTION CYCLE COUNT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
i = INTERRUPT
ii = INTERRUPT INSTRUCTION WORD
n = NORMAL INSTRUCTION WORD
i% = INTERRUPT REJECTED
INTERRUPT SYNCHRONIZED AND
RECOGNIZED AS PENDING
INTERRUPTS RE-ENABLED
(b) Program Controller Pipeline
Figure 7-14 Interrupting Sequential REP Instructions
REPEAT m
TIMES