ports/psoc6: Added comments on Timer calculation.

Signed-off-by: IFX-Anusha <Anusha.TR@infineon.com>

ports/psoc6/machine_timer.c

@@ -51,25 +51,25 @@ static mp_obj_t machine_timer_init_helper(machine_timer_obj_t *self, size_t n_ar
 
  if (args[ARG_freq].u_obj != mp_const_none) {
  self->freq = args[ARG_freq].u_int;
- period = 1.0f / (float)(args[ARG_freq].u_int);
+ period = 1.0f / (float)(args[ARG_freq].u_int); // Frequency to period conversion
  } else {
  self->period = args[ARG_period].u_int;
- period = (float)args[ARG_period].u_int / 1000.0f;
+ period = (float)args[ARG_period].u_int / 1000.0f; // ms to s conversion
  }
 
  if (args[ARG_callback].u_obj != mp_const_none) {
  self->callback = args[ARG_callback].u_obj;
  }
 
 
- uint32_t period_hal;
- uint32_t fz_hal = 1000000;
- period_hal = (uint32_t)(period * fz_hal) - 1;
+ uint32_t period_hal; // Period/count input for the PSoC6 HAL timer configuration
+ uint32_t fz_hal = 1000000; // Frequency for the PSoC timer clock is fixed as 1 MHz
+ period_hal = (uint32_t)(period * fz_hal) - 1; // Overflow Period = (Period + 1)/ frequency ;period = (overflow period * frequency)-1
 
-// Adjust fz_hal if necessary
+ // Adjust the frequency & recalculate the period if period/count is greater than the maximum overflow value for a 32 bit timer ie; 2^32
  while (period_hal > 4294967296) {
  fz_hal = fz_hal / 10; // Reduce the fz_hal value by 10%
- period_hal = (uint32_t)(period * fz_hal) - 1; // Recalculate period_hal
+ period_hal = (uint32_t)(period * fz_hal) - 1; // Recalculate Period input for the PSoC6 HAL timer configuration
  }
 
  // Timer initialisation of port
@@ -78,10 +78,10 @@ static mp_obj_t machine_timer_init_helper(machine_timer_obj_t *self, size_t n_ar
  const cyhal_timer_cfg_t timer_cfg =
  {
  .compare_value = 0, /* Timer compare value, not used */
- .period = period_hal, /* Defines the timer period */
+ .period = period_hal,  /* Defines the timer period */
  .direction = CYHAL_TIMER_DIR_UP, /* Timer counts up */
  .is_compare = false, /* Don't use compare mode */
- .is_continuous = self->mode,  /* Run the timer */
+ .is_continuous = self->mode, /* Run the timer */
  .value = 0 /* Initial value of counter */
  };