I am trying to configure an isr on the K20P100 dev kit (TWRK20D) to blink a LED, using the demo_gpio.c example as basis.
Here's my init routine called by main:
// enable PIT clock
SIM_SCGC6 |= SIM_SCGC6_PIT_MASK;
// enable PIT clock, freeze in debug
PIT_MCR = 0x01;
// set PIT 3
PIT_LDVAL3 = 5000000; // setup timer for 5000000 cycles
PIT_TCTRL3 = PIT_TCTRL_TIE_MASK // enable timer interrupt
| PIT_TCTRL_TEN_MASK; // enable timer
NVICICPR2 |= 1 << (71%32);
NVICISER2 |= 1 << (71%32);
in the isr.h, I added this:
#define VECTOR_87 isr_pit3
extern void isr_pit3(void);
then I added in demo_gpio.c:
PIT_TFLG3 |= 1;
GPIOC_PTOR |= 1<<PIN_LED_2;
This code doesn't work, execution never goes to isr_pit3() function.
Am I missing something?