Typical Isr - Texas Instruments TMS320C28x Reference Manual

Standard Operation for Maskable Interrupts
Example 3−1. Typical ISR
3-16
If you want the ISR to inform a peripheral that the interrupt is being serv-
iced, you can use the IACK instruction to send an interrupt acknowledge
signal. The IACK instruction accepts a 16-bit constant as an operand. For
a detailed description of the IACK instruction, see Chapter 6, C28x As-
sembly Language Instructions.
14) Program continues. If the interrupt is not approved by the CPU, the inter-
rupt is ignored, and the program continues uninterrupted. If the interrupt
is approved, its interrupt service routine is executed and the program con-
tinues where it left off (at the return address).
C28x Full Context Save/Restore
INTX: .;
PUSH
PUSH
PUSH
PUSH
PUSH
PUSH
PUSH
PUSH
; +8 = 16 cycles
.
.
.
POP
POP
POP
POP
POP
POP
POP
POP
IRET
;
8 cycles
AR1H:AR0H
XAR2
XAR3
XAR4
XAR5
XAR6
XAR7
XT
XT
XAR7
XAR6
XAR5
XAR4
XAR3
XAR2
XAR1H;AR0H
16 cycles
; 32-bit
; 32-bit
; 32-bit
; 32-bit
; 32-bit
; 32-bit
; 32-bit
; 32-bit