2019-09-04 02:55 AM
Hi,
In one of my project I am using STM32H750 controller.I want to measure the pulse width which is an input to the controller whose width will be in some nanoseconds so I want to configure the timer in a way that it can support to start the count from 5 nanoseconds .Is this achievable with this controller ? If not, what is the least (or) minimum supported time that I can start to count with this controller?
Actually I have tried the TIM2 in way to achieve 40 nanoseconds as start count but it is not giving the actual width of the pulse that is occurring . Have a look on the below provided timer configuration that I have done.
static void MX_TIM2_Init(void)
{
/* USER CODE BEGIN TIM2_Init 0 */
/* USER CODE END TIM2_Init 0 */
TIM_ClockConfigTypeDef sClockSourceConfig = {0};
TIM_MasterConfigTypeDef sMasterConfig = {0};
/* USER CODE BEGIN TIM2_Init 1 */
/* USER CODE END TIM2_Init 1 */
htim2.Instance = TIM2;
htim2.Init.Prescaler = 8;
htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
htim2.Init.Period = 0xFFFF;
htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
if (HAL_TIM_Base_Init(&htim2) != HAL_OK)
{
Error_Handler();
}
sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
if (HAL_TIM_ConfigClockSource(&htim2, &sClockSourceConfig) != HAL_OK)
{
Error_Handler();
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN TIM2_Init 2 */
/* USER CODE END TIM2_Init 2 */
}
The system core clock frequency is 400 MHz.
Thanks,
Parvathi.
2019-09-04 05:13 AM
Set Prescaler to ZERO, and Period to 0xFFFFFFFF, this will provide for maximal precision.
Use PWM Input mode