Timer 2(32 bit timer) in running mode to provide timer tick at 1ms. controller - STM32F072VB timer - TIMER 2 mode - up counting mode This timer should get TIm->CNT increment at 1 ms. then what should be the prescalar??

[Bs.1]

here is settings i did..but little bit confused about prescalar value

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 = 0;

 htim2.Init.CounterMode = TIM_COUNTERMODE_UP;

 htim2.Init.Period = 0xFFFFFFFF;//0;

 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 */

}

[waclawek.jan]

If you want TIM_CNT to increment at 1ms rate, set the prescaler to timer input clock frequency / 1000 -1. So, for example, if the system frequency is 48MHz and APB divider is 1, set the prescaler to 47999.

JW

[Bs.1]

Actually i trying to do this but not got the proper result...

I want to achieve is, my timer 2 should count from 0 to max level i.e 0xFFFFFFFF.

and using this timer count(TIM->CNT) i want to handle led on/off operations for 70 leds...

whenever led ON command is received i am saving timer current count i.e TIM->CNT in uint32 variable.

and after every 20ms it should on & off...below is the code...

To start the timer i am using this API:

 HAL_TIM_Base_Start(&htim2);

using structure to save counts:

struct

{

uint32_t timerValue;

uint8_t ledAction;

}L1,L2,L3,L4,L5,L6,L7,L8,L9,L10;

while(1)

{

L1.timerValue = __HAL_TIM_GetCounter(&htim2);

if(nled21val == 0)

{

//turn on led

HAL_GPIO_WritePin(GPIOE, LR2_Pin, GPIO_PIN_SET);

nled21val = L21.timerValue + 20;

}

else if(L21.timerValue >= nled21val)

{

//turn off led

HAL_GPIO_WritePin(GPIOE, LR2_Pin, GPIO_PIN_RESET);

nled21val = 0;

}

}