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Interrupt Handler for RTKSetIRQHandler

This method of installing interrupt handler is deprecated. Please see section Installing Shared Interrupt Handlers for the recommended method.

An interrupt handler to be installed with RTKSetIRQHandler should have the following structure:

• It should be declared as a void C/C++ function without parameters.
• While accepting the interrupt, the processor has masked all interrupts. To reenable interrupts of higher priorities, the handler should call RTKEnableInterrupts as its first statement.
• Subsequently, the hardware that has generated the interrupt should be serviced, if required. The handler can communicate with other tasks using mechanisms that cannot lead to blocking task switches.
• Finally, RTKIRQEnd should be called.

Example:

#define IRQ 3 
void RTKAPI IntHandler(void)    // high level interrupt handler in C 
{ 
   char Data; 
   RTKEnableInterrupts();       // allow higher level interrupts 
   RTIn(IOBASE+LSR);            // clear line status errors 
   Data = RTIn(IOBASE+RXB);     // get the received byte 
   RTKPutCond(Buffer, &Data);   // and insert in mailbox 
   RTKIRQEnd(IRQ);              // done 
} 
... 
int main(void) 
{ 
   ... 
   RTKSetIRQHandler(IRQ, IntHandler);   // install handler 
   RTKEnableIRQ(IRQ);                   // enable IRQ 
   // program device to start sending interrupts here 
   ... 
   RTKDisableIRQ(IRQ);                  // disable IRQ 
   ... 
 }

Interrupt Handling

Installing Shared Interrupt Handlers