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Function RTKRestoreIRQHandlerFar

RTKRestoreIRQHandlerFar can restore an interrupt handler previously saved using RTKSaveIRQHandlerFar:

void RTKRestoreIRQHandlerFar(int IRQ, const RTKIRQDescriptor * Handler);

Parameters

IRQ

Specifies the desired interrupt.

Handler

Pointer to a previously saved RTKIRQDescriptor structure.

Example:

To insert your own handler into an existing interrupt chain, you should use the following code:

#define IRQ ??                 // desired IRQ 
RTKIRQDescriptor OrgHandler; 
void MyHandler(void)           // application handler 
{ 
   ...                         // the handler's processing 
   RTKCallIRQHandlerFar(&OrgHandler); // call the old handler 

void Install(void)             // install MyHandler 
{ 
   RTKSaveIRQHandlerFar(IRQ, &OrqHandler); 
   RTKSetIRQHandler(MyHandler); 
} 

void CleanUp(void)             // deinstall MyHandler 
{ 
   RTKRestoreIRQHandlerFar(IRQ, &OrgHandler); 
}

Please note that restoring interrupt handlers is not always required at program exit. RTKernel-32 restores all modified interrupt vectors when the program terminates.

Instead of chaining, it is recommended to use RTInstallSharedIRQHandlerEx to install several handlers on the same IRQ.

Function RTKSaveIRQHandlerFar

Function RTKCallIRQHandlerFar