ardupilot/libraries/AP_HAL_AVR/utility/ISRRegistry.h

#ifndef __AP_HAL_AVR_ISR_REGISTRY_H__
#define __AP_HAL_AVR_ISR_REGISTRY_H__

#include <AP_HAL/AP_HAL.h>
#include <AP_HAL_AVR/AP_HAL_AVR_Namespace.h>

#define ISR_REGISTRY_TIMER2_OVF  0
#define ISR_REGISTRY_TIMER4_CAPT 1
#define ISR_REGISTRY_TIMER5_CAPT 2
#define ISR_REGISTRY_NUM_SLOTS   3

class AP_HAL_AVR::ISRRegistry {
public:
    int register_signal(int isr_number, AP_HAL::Proc proc);
    int unregister_signal(int isr_number);
    
    static AP_HAL::Proc _registry[ISR_REGISTRY_NUM_SLOTS];
};

#endif // __AP_HAL_AVR_ISR_REGISTRY_H__