diff options
Diffstat (limited to 'stmhal/timer.c')
| -rw-r--r-- | stmhal/timer.c | 42 |
1 files changed, 40 insertions, 2 deletions
diff --git a/stmhal/timer.c b/stmhal/timer.c index 1e77f0fea..26524fbdd 100644 --- a/stmhal/timer.c +++ b/stmhal/timer.c @@ -19,6 +19,7 @@ // the interrupts to be dispatched, so they are all collected here. // // TIM3: +// - flash storage controller, to flush the cache // - USB CDC interface, interval, to check for new data // - LED 4, PWM to set the LED intensity // @@ -27,6 +28,10 @@ TIM_HandleTypeDef TIM3_Handle; TIM_HandleTypeDef TIM5_Handle; +TIM_HandleTypeDef TIM6_Handle; + +// Used to divide down TIM3 and periodically call the flash storage IRQ +static uint32_t tim3_counter = 0; // TIM3 is set-up for the USB CDC interface void timer_tim3_init(void) { @@ -34,8 +39,8 @@ void timer_tim3_init(void) { __TIM3_CLK_ENABLE(); TIM3_Handle.Instance = TIM3; - TIM3_Handle.Init.Period = (USBD_CDC_POLLING_INTERVAL*1000) - 1; - TIM3_Handle.Init.Prescaler = 84-1; + TIM3_Handle.Init.Period = (USBD_CDC_POLLING_INTERVAL*1000) - 1; // TIM3 fires every USBD_CDC_POLLING_INTERVAL ms + TIM3_Handle.Init.Prescaler = 84-1; // for System clock at 168MHz, TIM3 runs at 1MHz TIM3_Handle.Init.ClockDivision = 0; TIM3_Handle.Init.CounterMode = TIM_COUNTERMODE_UP; HAL_TIM_Base_Init(&TIM3_Handle); @@ -57,6 +62,7 @@ void timer_tim3_deinit(void) { */ // TIM5 is set-up for the servo controller +// This function inits but does not start the timer void timer_tim5_init(void) { // TIM5 clock enable __TIM5_CLK_ENABLE(); @@ -74,10 +80,42 @@ void timer_tim5_init(void) { HAL_TIM_PWM_Init(&TIM5_Handle); } +// Init TIM6 with a counter-overflow at the given frequency (given in Hz) +// TIM6 is used by the DAC and ADC for auto sampling at a given frequency +// This function inits but does not start the timer +void timer_tim6_init(uint freq) { + // TIM6 clock enable + __TIM6_CLK_ENABLE(); + + // Timer runs at SystemCoreClock / 2 + // Compute the prescaler value so TIM6 triggers at freq-Hz + uint32_t period = (SystemCoreClock / 2) / freq; + uint32_t prescaler = 1; + while (period > 0xffff) { + period >>= 1; + prescaler <<= 1; + } + + // Time base clock configuration + TIM6_Handle.Instance = TIM6; + TIM6_Handle.Init.Period = period - 1; + TIM6_Handle.Init.Prescaler = prescaler - 1; + TIM6_Handle.Init.ClockDivision = 0; // unused for TIM6 + TIM6_Handle.Init.CounterMode = TIM_COUNTERMODE_UP; // unused for TIM6 + HAL_TIM_Base_Init(&TIM6_Handle); +} + // Interrupt dispatch void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim) { if (htim == &TIM3_Handle) { USBD_CDC_HAL_TIM_PeriodElapsedCallback(); + + // Periodically raise a flash IRQ for the flash storage controller + if (tim3_counter++ >= 500 / USBD_CDC_POLLING_INTERVAL) { + tim3_counter = 0; + NVIC->STIR = FLASH_IRQn; + } + } else if (htim == &TIM5_Handle) { servo_timer_irq_callback(); } |