Interrupt Handling - Analog Devices ADSP-TS101 TigerSHARC Hardware Reference Manual

7. If the nesting was enabled, the ISR should:
• Restore
• Restore context
•
RTI
!
Instructions for restoring
the software.
8. Finally:
•
PMASKN
• If hardware interrupt,
• Jump to

Interrupt Handling

There are two methods of interrupt handling: one that uses nesting and
one that does not. If the interrupt handling does not use nesting, other
interrupts are disabled throughout the ISR or handling routine, because
Bit60 in
PMASK
ing, some special programming is required. The special programming
required for nested interrupt handling routines is described in this section.
The first instructions in the interrupt routine must be dedicated to pre-
serving the current status of the machine. All the registers used by the
interrupt routine must be pushed onto a stack. The TigerSHARC proces-
sor does not require a dedicated stack pointer since any one of the IALU
registers can be used as a stack pointer. The application can store and load
registers with the post-modify option, and it can work with two stacks in
two memories and store eight words every cycle.
is an aliased name for
RETIB
simultaneously setting or clearing
writing or reading).
ADSP-TS101 TigerSHARC Processor
Hardware Reference
: which automatically sets
RETIB
RETIB
cleared
RETI
is set. If the interrupt handling routine does enable nest-
. If you use
RETI
and context have to be specified in
cleared
PMASK60
, you access
RETIB
(depending on whether you are
PMASK60
Interrupts
PMASK60
while
RETI
4-19