Add attachInterruptVector()

teensy3/core_pins.h

 static inline void analogWriteResolution(uint32_t bits) { analogWriteRes(bits); }
 void analogWriteFrequency(uint8_t pin, uint32_t frequency);
 void analogWriteDAC0(int val);
+#ifdef __cplusplus
+void attachInterruptVector(IRQ_NUMBER_t irq, void (*function)(void));
+#else
+void attachInterruptVector(enum IRQ_NUMBER_t irq, void (*function)(void));
+#endif
 void attachInterrupt(uint8_t pin, void (*function)(void), int mode);
 void detachInterrupt(uint8_t pin);
 void _init_Teensyduino_internal_(void);

teensy3/kinetis.h

 
 #include <stdint.h>
 
-#ifdef __cplusplus
-#define BEGIN_ENUM(NAME) enum name {
-#define END_ENUM(NAME)   };
-#else
-#define BEGIN_ENUM(NAME) typedef enum {
-#define END_ENUM(NAME)   } name;
-#endif
-
 // Teensy 3.0
 #if defined(__MK20DX128__)
-BEGIN_ENUM(IRQ_NUMBER_t)
+enum IRQ_NUMBER_t {
 	IRQ_DMA_CH0 =		0,
 	IRQ_DMA_CH1 =		1,
 	IRQ_DMA_CH2 =		2,
 	IRQ_PORTD =		43,
 	IRQ_PORTE =		44,
 	IRQ_SOFTWARE =		45
-END_ENUM(IRQ_NUMBER_t)
+};
 #define NVIC_NUM_INTERRUPTS	46
 #define DMA_NUM_CHANNELS	4
 #define KINETISK_UART0
 
 // Teensy 3.1
 #elif defined(__MK20DX256__)
-BEGIN_ENUM(IRQ_NUMBER_t)
+enum IRQ_NUMBER_t {
 	IRQ_DMA_CH0 =		0,
 	IRQ_DMA_CH1 =		1,
 	IRQ_DMA_CH2 =		2,
 	IRQ_PORTD =		90,
 	IRQ_PORTE =		91,
 	IRQ_SOFTWARE =		94
-END_ENUM(IRQ_NUMBER_t)
+};
 #define NVIC_NUM_INTERRUPTS	95
 #define DMA_NUM_CHANNELS	16
 #define KINETISK_UART0

teensy3/pins_teensy.c

 	// fast interrupts will still be serviced quickly?
 }
 
+void attachInterruptVector(enum IRQ_NUMBER_t irq, void (*function)(void))
+{
+	_VectorsRam[irq + 16] = function;
+}
+
 void attachInterrupt(uint8_t pin, void (*function)(void), int mode)
 {
 	volatile uint32_t *config;