Interrupt Processing
4-52
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
Supervisor stack. Processor state is stored in the Supervisor stack, not in
the User stack. Hence, the instructions to push
RETI
(
[--SP] = RETI
) and
pop
RETI
(
RETI = [SP++]
) use the Supervisor stack.
Figure 4-8. Non-nested Interrupt Handling
IF 1
IF 2
IF 3
DEC
AC
DF1
DF2
EX1
EX2
WB
A8
1
2
CYCLE:
A9
A7
A6
A5
A4
A3
A2
A1
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A1 0
A1 0
A9
A8
A7
A6
A5
A4
A3
A2
I0
I2
I1
I0
I1
I0
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
. . .
A3
A4
A5
A6
A7
A3
A4
A5
A6
A3
A4
A5
A4
A3
A3
In
In
INTERRUPTS DISABLED
DURING THIS INTERVAL.
CYCLE 1: INTERRUPT IS LATCHED. ALL POSSIBLE INTERRUPT SOURCES DETERMINED.
CYCLE 2: INTERRUPT IS PRIORITIZED.
CYCLE 3: ALL INSTRUCTIONS ABOVE A2 ARE KILLED. A2 IS KILLED IF IT IS AN RTI OR CLI
INSTRUCTION. ISR STARTING ADDRESS LOOKUP OCCURS.
CYCLE 4: I0 (INSTRUCTION AT START OF ISR) ENTERS PIPELINE.
CYCLE M: WHEN THE RTI INSTRUCTION REACHES THE DF1 STAGE, INSTRUCTION A3 IS
FETCHED IN PREPARATION FOR RETURNING FROM INTERRUPT.
CYCLE M+4: RTI HAS REACHED WB STAGE, RE-ENABLING INTERRUPTS.
m
m+1
m+2
m+3
m+4
6
5
4
3
In-1
In-1
In-1
In
In-2
In-2
In-3
RTI
RTI
RTI
RTI
RTI
PIPELINE
STAGE
Summary of Contents for ADSP-BF53x Blackfin
Page 38: ...Conventions xxxviii ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 134: ...System Reset and Powerup 3 18 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 324: ...Instruction Overview 7 20 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 486: ...Instruction Overview 13 28 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 512: ...Instruction Overview 14 26 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 604: ...Instruction Overview 15 92 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 688: ...Instruction Overview 18 48 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 742: ...Instruction Overview 19 54 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 752: ...Examples 20 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 790: ...ADSP BF535 Flags A 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 800: ...Performance Monitor Registers B 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 1042: ...Index I 40 ADSP BF53x BF56x Blackfin Processor Programming Reference...