autodemo/timer3.c

   1 #include <timer3.h>
   2 #include <mcu_regs.h>
   3 #include <cpu_def.h>
   4
   5 static volatile timer_t timer;
   6
   7 static void  timer_isr(void) __attribute__ ((interrupt_handler));
   8
   9 static void
  10 timer_isr(void)
  11 {
  12     timer++;
  13     *TPU_TSR3 &= ~TSR2_TCFVm ; //reset overflow flag (clear interrupt)
  14 }
  15
  16 //timer initialisation
  17 /*free running counter*/
  18 void init_timer3()
  19 {
  20     *SYS_MSTPCRA &= ~MSTPCRA_TPUm; // power TPU unit
  21
  22     *TPU_TCR3 =0x00 | 0x06;     //rising edge, f divided by 256
  23     *TPU_TMDR3 =0x00;           // normal mode
  24     *TPU_TSR3 &= ~TSR3_TCFVm ;  //reset overflow flag
  25     *TPU_TIER3 |=TIER3_TCIEVm;  //enable overflow interrupt
  26
  27     *TPU_TSTR |=TSTR_CST3m;     //start timer
  28
  29     excptvec_set(52, timer_isr);
  30 }
  31
  32 timer_t get_timer()
  33 {
  34   return timer;
  35 }