LL_LPTIM_Init and LL_LPTIM_DeInit APIs migration

The LL initialization and de-initialization functions previously available in the stm32tnxx_ll_lptim.c files within HAL1 are no longer present in HAL2. In HAL2, all LL C files ( stm32tnxx_ll_lptim.c) have been removed, leaving only the LL header files ( stm32tnxx_ll_lptim.h) that contain static inline functions.

If users need to initialize or de-initialize LPTIM using the LL layer, they have two methods:

  • Utilize STM32CubeMX2 Code Generation: Rely on STM32CubeMX2 to generate code with the LL layer for LPTIM initialization and de-initialization.

  • Replace manually the initialization and de-initialization functionsReplace the LL_LPTIM_Init and LL_LPTIM_DeInit functions

    manually with equivalent sequences using the static inline functions provided in the stm32tnxx_ll_lptim.h file, tailored to their specific configuration and requirements.

This approach ensures that the initialization and de-initialization sequences are precisely addressing the given use case based on the LL static inline functions provided in the stm32tnxx_ll_lptim.h header file. The sequences offer improved footprint optimization compared to the previous LL initialization functions found in stm32tnxx_ll_lptim.c.

Related concept: Remove stm32tnxx_ll_ppp.c files

Method 1: Utilize STM32CubeMX2 Code Generation

LL LPTIM configuration panel

Create a new project with the STM32CubeMX2, then start the initialization and the main configuration.

Example Image

LPTIM main features configuration

Configure the LPTIM main features.

LPTIM main features configuration

LPTIM advanced features configuration

Configure the LPTIM advanced features.

LPTIM advanced features configuration

GPIO configuration

Configure GPIO pins.

LPTIM GPIO configuration

DMA configuration

Configure the DMA for data reception as needed.

LPTIM DMA configuration

NVIC configuration

Configure the NVIC in case of an interrupt.

LPTIM NVIC configuration

Generated LPTIM initialization sequence

The LPTIM initialization and de-initialization sequences are generated in the mx_lptim1_init and mx_lptim1_deinit functions in mx_lptim1.c file under $YOUR_PROJECT_NAME$/$YOUR_PROJECT_NAME$_SW/generated/STM32Cube_CodeGen.

STM32CubeMX2 Generated : LPTIM initialization sequence

Topic

Code Snippet HAL1

Code Snippet HAL2

Initialization and configuration sequence 

static void MX_LPTIM1_Init(void)
{
  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

/* Enable the interruption for LPTIM */
  NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_4);
  NVIC_SetPriority(SysTick_IRQn, NVIC_EncodePriority(NVIC_GetPriorityGrouping(),0, 0));

  /* Peripheral clock enable */
  LL_APB2_GRP1_EnableClock(LL_APB2_GRP1_PERIPH_LPTIM1);

 /*Configure the low power timer's time-base unit.*/
  LL_LPTIM_Enable(LPTIM1);

  LL_LPTIM_ClearFlag_REPOK(LPTIM1);
  LL_LPTIM_SetRepetition(LPTIM1, 0);

   /* Wait till REPOK Flag is ready */
  while(!LL_LPTIM_IsActiveFlag_REPOK(LPTIM1))
  {
  }



  LL_LPTIM_ClearFlag_ARROK(LPTIM1);
  LL_LPTIM_SetAutoReload(LPTIM1, 65535);


   /* Wait till ARROK Flag is ready */
  while(!LL_LPTIM_IsActiveFlag_ARROK(LPTIM1))
  {
  }




  LL_LPTIM_Disable(LPTIM1);
  LL_LPTIM_SetClockSource(LPTIM1, LL_LPTIM_CLK_SOURCE_INTERNAL);
  LL_LPTIM_SetPrescaler(LPTIM1, LL_LPTIM_PRESCALER_DIV1);
  LL_LPTIM_Enable(LPTIM1);

/*Configure the Output channel/Output Compare*/
  LL_LPTIM_OC_SetPolarity(LPTIM1, LL_LPTIM_CHANNEL_CH1, LL_LPTIM_OUTPUT_POLARITY_REGULAR);

  LL_LPTIM_SetCompareCH1(LPTIM1, 1);

   /* Wait till CMP1OK Flag is ready */
  while(!LL_LPTIM_IsActiveFlag_CMP1OK(LPTIM1))
  {
  }




  LL_LPTIM_ClearFlag_CMP1OK(LPTIM1);
  LL_LPTIM_CC_SetChannelMode(LPTIM1, LL_LPTIM_CHANNEL_CH1, LL_LPTIM_CCMODE_OUTPUT_PWM);
  LL_LPTIM_Disable(LPTIM1);

  /* GPIOB Clock enable */
  LL_AHB4_GRP1_EnableClock(LL_AHB4_GRP1_PERIPH_GPIOB);


  /**LPTIM1 GPIO Configuration**/
  GPIO_InitStruct.Pin = LL_GPIO_PIN_2;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  GPIO_InitStruct.Alternate = LL_GPIO_AF_9;
  LL_GPIO_Init(GPIOB, &GPIO_InitStruct);

}

LPTIM_TypeDef *mx_lptim1_init(void)
{
  LL_APB2_GRP1_EnableClock(LL_APB2_GRP1_PERIPH_LPTIM1);

  /* LPTIM1 interrupt Init */
  NVIC_SetPriority(LPTIM1_IRQn, NVIC_EncodePriority(NVIC_GetPriorityGrouping(),0, 0));
  NVIC_EnableIRQ(LPTIM1_IRQn);

/* Peripheral clock enable */
  LL_APB2_GRP1_EnableClock(LL_APB2_GRP1_PERIPH_LPTIM1);

/*Configure the low power timer's time-base unit.*/
  LL_LPTIM_Enable(LPTIM1);
  LL_LPTIM_WRITE_REG(LPTIM1, ICR, LL_LPTIM_FLAG_ALL);
  LL_LPTIM_SetRepetition(LPTIM1, 0x0000);

  tickstart = HAL_GetTick();
  while (LL_LPTIM_IsActiveFlag_REPOK(LPTIM1) == 0)
  {
    if ((HAL_GetTick() - tickstart) > 1000UL)
    {
      break;
    }
  }
  LL_LPTIM_ClearFlag_REPOK(LPTIM1);
  LL_LPTIM_SetAutoReload(LPTIM1, 0xFFFF);

  tickstart = HAL_GetTick();
  while (LL_LPTIM_IsActiveFlag_ARROK(LPTIM1) == 0)
  {
    if ((HAL_GetTick() - tickstart) > 1000UL)
    {
      break;
    }
  }
  LL_LPTIM_ClearFlag_ARROK(LPTIM1);
  LL_LPTIM_Disable(LPTIM1);
  LL_LPTIM_SetClockSource(LPTIM1, LL_LPTIM_CLK_SOURCE_INTERNAL);
  LL_LPTIM_SetCounterMode(LPTIM1, LL_LPTIM_COUNTER_MODE_INTERNAL);
  LL_LPTIM_SetPrescaler(LPTIM1, LL_LPTIM_PRESCALER_DIV1);

  /*Configure the Output channel/Output Compare*/
  LL_LPTIM_OC_SetPolarity(LPTIM1, LL_LPTIM_CHANNEL_CH1, LL_LPTIM_OCPOLARITY_HIGH );
  LL_LPTIM_Enable(LPTIM1);
  LL_LPTIM_WRITE_REG(LPTIM1, ICR, LL_LPTIM_ISR_CMP1OK);
  LL_LPTIM_OC_SetCompareCH1(LPTIM1, 1);

  tickstart = HAL_GetTick();
  while (LL_LPTIM_IsActiveFlag_CMP1OK(LPTIM1) == 0)
  {
    if ((HAL_GetTick() - tickstart) > 1000UL)
    {
      break;
    }
  }
  LL_LPTIM_ClearFlag_CMP1OK(LPTIM1);
  LL_LPTIM_Disable(LPTIM1);
  LL_LPTIM_CC_SetChannelMode(LPTIM1, LL_LPTIM_CHANNEL_CH1, LL_LPTIM_CCMODE_OUTPUT_PWM);

  /* GPIO Clock Enable */
  LL_AHB4_GRP1_EnableClock(LL_AHB4_GRP1_PERIPH_GPIOB);

  /* GPIO Configuration*/

  LL_GPIO_SetPinMode(GPIOB, LL_GPIO_PIN_2, LL_GPIO_MODE_ALTERNATE);
  LL_GPIO_SetPinSpeed(GPIOB, LL_GPIO_PIN_2, LL_GPIO_SPEED_FREQ_LOW);
  LL_GPIO_SetPinOutputType(GPIOB, LL_GPIO_PIN_2, LL_GPIO_OUTPUT_PUSHPULL);
  LL_GPIO_SetPinPull(GPIOB, LL_GPIO_PIN_2, LL_GPIO_PULL_NO);
  LL_GPIO_SetAFPin_0_7(GPIOB, LL_GPIO_PIN_2, LL_GPIO_AF_9);

  return LPTIM1;
}

Deinitialization sequence 

void MX_LPTIM1_DeInit(void)
{
  LL_LPTIM_DeInit(LPTIM1);



/* ### GPIO deinitialization of LPTIM1: LPTIM1_CH1 ########################### */

  LL_AHB4_GRP1_ForceReset(LL_AHB4_GRP1_PERIPH_GPIOB);
  LL_AHB4_GRP1_ReleaseReset(LL_AHB4_GRP1_PERIPH_GPIOB);
}

void mx_lptim1_deinit(void)
{
  LL_APB2_GRP1_ForceReset(LL_APB2_GRP1_PERIPH_LPTIM1);
  LL_APB2_GRP1_ReleaseReset(LL_APB2_GRP1_PERIPH_LPTIM1);

  LL_APB2_GRP1_DisableClock(LL_APB2_GRP1_PERIPH_LPTIM1);

  /* Disable the LPTIM global interruption */
  NVIC_DisableIRQ(LPTIM1_IRQn);
}

Method 2: Replace manually the initialization and de-initialization functions

HAL1

HAL2

Case of LPTIM_timebase configuration 

/* To fill the fields of the LPTIMx timebase there are two ways*/
LL_LPTIM_InitTypeDef LPTIM_InitStruct;

/*The first method*/
/* Set the default configuration */
LL_LPTIM_StructInit(&LPTIM_InitStruct);

 /*Or*/

/*The second method*/
/* Set the selected configuration */
LPTIM_InitStruct->ClockSource = LL_LPTIM_CLK_SOURCE_INTERNAL;
LPTIM_InitStruct->Prescaler   = LL_LPTIM_PRESCALER_DIV1;
LPTIM_InitStruct->Waveform    = LL_LPTIM_OUTPUT_WAVEFORM_PWM;
LPTIM_InitStruct->Polarity    = LL_LPTIM_OUTPUT_POLARITY_REGULAR;

LL_LPTIM_Init(LPTIM1, &LPTIM_InitStruct);

/***********/










LL_LPTIM_SetClockSource(LPTIM1, LL_LPTIM_CLK_SOURCE_INTERNAL)
LL_LPTIM_SetPrescaler(LPTIM1, LL_LPTIM_PRESCALER_DIV1)
LL_LPTIM_SetWaveform(LPTIM1, LL_LPTIM_OC_WAVEFORM_PWM)
LL_LPTIM_OC_SetPolarity(LPTIM1, LL_LPTIM_CHANNEL_CH1 ,LL_LPTIM_OUTPUT_POLARITY_REGULAR)

LL_LPTIM_DeInit() API Migration

According to the used LPTIM instance, implement the precise calls to LL_APB2_GRP1_ForceReset() and LL_APB2_GRP1_ReleaseReset().

Comparison of HAL1 and HAL2

HAL1

HAL2 

LL_LPTIM_DeInit(LPTIM1);

LL_APB2_GRP1_ForceReset(LL_APB2_GRP1_PERIPH_LPTIM1);
LL_APB2_GRP1_ReleaseReset(LL_APB2_GRP1_PERIPH_LPTIM1);