/** ****************************************************************************** * @file Examples_LL/TIM/TIM_PWMOutput/Src/main.c * @author MCD Application Team * @brief This example describes how to use a timer peripheral to generate a * PWM output signal and update PWM duty cycle * using the STM32F1xx TIM LL API. * Peripheral initialization done using LL unitary services functions. ****************************************************************************** * @attention * *

© Copyright (c) 2016 STMicroelectronics. * All rights reserved.

* * This software component is licensed by ST under BSD 3-Clause license, * the "License"; You may not use this file except in compliance with the * License. You may obtain a copy of the License at: * opensource.org/licenses/BSD-3-Clause * ****************************************************************************** */ /* Includes ------------------------------------------------------------------*/ #include "main.h" /** @addtogroup STM32F1xx_LL_Examples * @{ */ /** @addtogroup TIM_PWMOutput * @{ */ /* Private typedef -----------------------------------------------------------*/ /* Private define ------------------------------------------------------------*/ /* Number of output compare modes */ #define TIM_DUTY_CYCLES_NB 11 /* Private macro -------------------------------------------------------------*/ /* Private variables ---------------------------------------------------------*/ /* Duty cycles: D = T/P * 100% */ /* where T is the pulse duration and P the period of the PWM signal */ static uint32_t aDutyCycle[TIM_DUTY_CYCLES_NB] = { 0, /* 0% */ 10, /* 10% */ 20, /* 20% */ 30, /* 30% */ 40, /* 40% */ 50, /* 50% */ 60, /* 60% */ 70, /* 70% */ 80, /* 80% */ 90, /* 90% */ 100, /* 100% */ }; /* Duty cycle index */ static uint8_t iDutyCycle = 0; /* Measured duty cycle */ __IO uint32_t uwMeasuredDutyCycle = 0; /* TIM2 Clock */ static uint32_t TimOutClock = 1; /* Private function prototypes -----------------------------------------------*/ __STATIC_INLINE void SystemClock_Config(void); __STATIC_INLINE void Configure_TIMPWMOutput(void); __STATIC_INLINE void Configure_DutyCycle(uint32_t OCMode); __STATIC_INLINE void UserButton_Init(void); /* Private functions ---------------------------------------------------------*/ /** * @brief Main program * @param None * @retval None */ int main(void) { /* Configure the system clock to 72 MHz */ SystemClock_Config(); /* Initialize button in EXTI mode */ UserButton_Init(); /* Configure the timer in output compare mode */ Configure_TIMPWMOutput(); /* Infinite loop */ while (1) { } } /** * @brief Configures the timer to generate a PWM signal on the OC1 output. * @note Peripheral configuration is minimal configuration from reset values. * Thus, some useless LL unitary functions calls below are provided as * commented examples - setting is default configuration from reset. * @param None * @retval None */ __STATIC_INLINE void Configure_TIMPWMOutput(void) { /*************************/ /* GPIO AF configuration */ /*************************/ /* Enable the peripheral clock of GPIOs */ LL_APB2_GRP1_EnableClock(LL_APB2_GRP1_PERIPH_GPIOA); /* GPIO TIM2_CH1 configuration */ LL_GPIO_SetPinMode(GPIOA, LL_GPIO_PIN_0, LL_GPIO_MODE_ALTERNATE); LL_GPIO_SetPinPull(GPIOA, LL_GPIO_PIN_0, LL_GPIO_PULL_DOWN); LL_GPIO_SetPinSpeed(GPIOA, LL_GPIO_PIN_0, LL_GPIO_SPEED_FREQ_HIGH); /***********************************************/ /* Configure the NVIC to handle TIM2 interrupt */ /***********************************************/ NVIC_SetPriority(TIM2_IRQn, 0); NVIC_EnableIRQ(TIM2_IRQn); /******************************/ /* Peripheral clocks enabling */ /******************************/ /* Enable the timer peripheral clock */ LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_TIM2); /***************************/ /* Time base configuration */ /***************************/ /* Set counter mode */ /* Reset value is LL_TIM_COUNTERMODE_UP */ //LL_TIM_SetCounterMode(TIM2, LL_TIM_COUNTERMODE_UP); /* Set the pre-scaler value to have TIM2 counter clock equal to 10 kHz */ LL_TIM_SetPrescaler(TIM2, __LL_TIM_CALC_PSC(SystemCoreClock, 10000)); /* Enable TIM2_ARR register preload. Writing to or reading from the */ /* auto-reload register accesses the preload register. The content of the */ /* preload register are transferred into the shadow register at each update */ /* event (UEV). */ LL_TIM_EnableARRPreload(TIM2); /* Set the auto-reload value to have a counter frequency of 100 Hz */ /* TIM2CLK = SystemCoreClock / (APB prescaler & multiplier) */ TimOutClock = SystemCoreClock/1; LL_TIM_SetAutoReload(TIM2, __LL_TIM_CALC_ARR(TimOutClock, LL_TIM_GetPrescaler(TIM2), 100)); /*********************************/ /* Output waveform configuration */ /*********************************/ /* Set output mode */ /* Reset value is LL_TIM_OCMODE_FROZEN */ LL_TIM_OC_SetMode(TIM2, LL_TIM_CHANNEL_CH1, LL_TIM_OCMODE_PWM1); /* Set output channel polarity */ /* Reset value is LL_TIM_OCPOLARITY_HIGH */ //LL_TIM_OC_SetPolarity(TIM2, LL_TIM_CHANNEL_CH1, LL_TIM_OCPOLARITY_HIGH); /* Set compare value to half of the counter period (50% duty cycle ) */ LL_TIM_OC_SetCompareCH1(TIM2, ( (LL_TIM_GetAutoReload(TIM2) + 1 ) / 2)); /* Enable TIM2_CCR1 register preload. Read/Write operations access the */ /* preload register. TIM2_CCR1 preload value is loaded in the active */ /* at each update event. */ LL_TIM_OC_EnablePreload(TIM2, LL_TIM_CHANNEL_CH1); /**************************/ /* TIM2 interrupts set-up */ /**************************/ /* Enable the capture/compare interrupt for channel 1*/ LL_TIM_EnableIT_CC1(TIM2); /**********************************/ /* Start output signal generation */ /**********************************/ /* Enable output channel 1 */ LL_TIM_CC_EnableChannel(TIM2, LL_TIM_CHANNEL_CH1); /* Enable counter */ LL_TIM_EnableCounter(TIM2); /* Force update generation */ LL_TIM_GenerateEvent_UPDATE(TIM2); } /** * @brief Changes the duty cycle of the PWM signal. * D = (T/P)*100 * where T is the pulse duration and P is the PWM signal period * @param D Duty cycle * @retval None */ __STATIC_INLINE void Configure_DutyCycle(uint32_t D) { uint32_t P; /* Pulse duration */ uint32_t T; /* PWM signal period */ /* PWM signal period is determined by the value of the auto-reload register */ T = LL_TIM_GetAutoReload(TIM2) + 1; /* Pulse duration is determined by the value of the compare register. */ /* Its value is calculated in order to match the requested duty cycle. */ P = (D*T)/100; LL_TIM_OC_SetCompareCH1(TIM2, P); } /** * @brief Configures User push-button in GPIO or EXTI Line Mode. * @param None * @retval None */ __STATIC_INLINE void UserButton_Init(void) { /* Enable the BUTTON Clock */ USER_BUTTON_GPIO_CLK_ENABLE(); /* Configure GPIO for BUTTON */ LL_GPIO_SetPinMode(USER_BUTTON_GPIO_PORT, USER_BUTTON_PIN, LL_GPIO_MODE_INPUT); LL_GPIO_SetPinPull(USER_BUTTON_GPIO_PORT, USER_BUTTON_PIN, LL_GPIO_PULL_DOWN); /* Connect External Line to the GPIO*/ USER_BUTTON_SYSCFG_SET_EXTI(); /* Enable a rising trigger EXTI line 13 Interrupt */ USER_BUTTON_EXTI_LINE_ENABLE(); USER_BUTTON_EXTI_FALLING_TRIG_ENABLE(); /* Configure NVIC for USER_BUTTON_EXTI_IRQn */ NVIC_EnableIRQ(USER_BUTTON_EXTI_IRQn); NVIC_SetPriority(USER_BUTTON_EXTI_IRQn,0x03); } /** * @brief System Clock Configuration * The system Clock is configured as follow : * System Clock source = PLL (HSE) * SYSCLK(Hz) = 72000000 * HCLK(Hz) = 72000000 * AHB Prescaler = 1 * APB1 Prescaler = 2 * APB2 Prescaler = 1 * HSE Frequency(Hz) = 8000000 * PLLMUL = 9 * Flash Latency(WS) = 2 * @param None * @retval None */ void SystemClock_Config(void) { /* Set FLASH latency */ LL_FLASH_SetLatency(LL_FLASH_LATENCY_2); /* Enable HSE oscillator */ LL_RCC_HSE_EnableBypass(); LL_RCC_HSE_Enable(); while(LL_RCC_HSE_IsReady() != 1) { }; /* Main PLL configuration and activation */ LL_RCC_PLL_ConfigDomain_SYS(LL_RCC_PLLSOURCE_HSE_DIV_1, LL_RCC_PLL_MUL_9); LL_RCC_PLL_Enable(); while(LL_RCC_PLL_IsReady() != 1) { }; /* Sysclk activation on the main PLL */ LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1); LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_PLL); while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_PLL) { }; /* Set APB1 & APB2 prescaler*/ LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_2); LL_RCC_SetAPB2Prescaler(LL_RCC_APB2_DIV_1); /* Set systick to 1ms in using frequency set to 72MHz */ LL_Init1msTick(72000000); /* Update CMSIS variable (which can be updated also through SystemCoreClockUpdate function) */ LL_SetSystemCoreClock(72000000); } /******************************************************************************/ /* USER IRQ HANDLER TREATMENT */ /******************************************************************************/ /** * @brief User button interrupt processing * @note When the user key button is pressed the PWM duty cycle is updated. * @param None * @retval None */ void UserButton_Callback(void) { /* Set new duty cycle */ iDutyCycle = (iDutyCycle + 1) % TIM_DUTY_CYCLES_NB; /* Change PWM signal duty cycle */ Configure_DutyCycle(aDutyCycle[iDutyCycle]); } /** * @brief Timer capture/compare interrupt processing * @param None * @retval None */ void TimerCaptureCompare_Callback(void) { uwMeasuredDutyCycle = (LL_TIM_OC_GetCompareCH1(TIM2) * 100) / ( LL_TIM_GetAutoReload(TIM2) + 1 ); } #ifdef USE_FULL_ASSERT /** * @brief Reports the name of the source file and the source line number * where the assert_param error has occurred. * @param file: pointer to the source file name * @param line: assert_param error line source number * @retval None */ void assert_failed(uint8_t *file, uint32_t line) { /* User can add his own implementation to report the file name and line number, ex: printf("Wrong parameters value: file %s on line %d", file, line) */ /* Infinite loop */ while (1) { } } #endif /** * @} */ /** * @} */ /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/