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Rabbit 3000 Microprocessor User’s Manual
26.3.7 Handling Interrupts in the System/User Mode
Interrupts, RSTs, SYSCALL, and SCALL all enter the System Mode automatically. There
will be times, however, that an interrupt should be handled in the User Mode. The solution
to this is for System Mode interrupt vector to reenter the User Mode before calling the
User Mode interrupt handler. An example of both system and user interrupt handling is
When enabled for User Mode access, a peripheral interrupt (if it is capable of generating
an interrupt) can only be requested at Priority 2 or 1.
Figure 26-4. Interrupt Handing in the System/User Mode
Application code (user)
Application ISR (user)
ISR
(system)
ISR
(system)
Application code (user)
ISR (system)
INTERRUPT UNDER SYSTEM CONTROL
INTERRUPT UNDER USER CONTROL