/** ****************************************************************************** * @file TIM/DMABurst/main.c * @author MCD Application Team * @version V3.5.0 * @date 08-April-2011 * @brief Main program body ****************************************************************************** * @attention * * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS. * *

© COPYRIGHT 2011 STMicroelectronics

****************************************************************************** */ /* Includes ------------------------------------------------------------------*/ #include "stm32f10x.h" /** @addtogroup STM32F10x_StdPeriph_Examples * @{ */ /** @addtogroup TIM_DMABurst * @{ */ /* Private typedef -----------------------------------------------------------*/ /* Private define ------------------------------------------------------------*/ #define TIM1_DMAR_ADDRESS ((uint32_t)0x40012C4C) /* TIM ARR (Auto Reload Register) address */ /* Private macro -------------------------------------------------------------*/ /* Private variables ---------------------------------------------------------*/ GPIO_InitTypeDef GPIO_InitStructure; DMA_InitTypeDef DMA_InitStructure; TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; TIM_OCInitTypeDef TIM_OCInitStructure; uint16_t SRC_Buffer[6] = {0x0FFF, 0x0000, 0x0555}; /* Private function prototypes -----------------------------------------------*/ /* Private functions ---------------------------------------------------------*/ /** * @brief Main program * @param None * @retval None */ int main(void) { /*!< At this stage the microcontroller clock setting is already configured, this is done through SystemInit() function which is called from startup file (startup_stm32f10x_xx.s) before to branch to application main. To reconfigure the default setting of SystemInit() function, refer to system_stm32f10x.c file */ /* TIM1 and GPIOA clock enable */ RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1 | RCC_APB2Periph_GPIOA, ENABLE); /* DMA clock enable */ RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE); /* GPIOA Configuration: Channel 1 as alternate function push-pull */ GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_Init(GPIOA, &GPIO_InitStructure); /* TIM1 DeInit */ TIM_DeInit(TIM1); /* DMA1 Channel5 Config */ DMA_DeInit(DMA1_Channel5); DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)TIM1_DMAR_ADDRESS; DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)SRC_Buffer; DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST; DMA_InitStructure.DMA_BufferSize = 3; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord; DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; DMA_InitStructure.DMA_Priority = DMA_Priority_High; DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; DMA_Init(DMA1_Channel5, &DMA_InitStructure); /* Time base configuration */ /* ----------------------------------------------------------------------- TIM1 Configuration: generate 1 PWM signal using the DMA burst mode: The TIM1CLK frequency is set to SystemCoreClock (Hz), to get TIM1 counter clock at 24 MHz the Prescaler is computed as following: - Prescaler = (TIM1CLK / TIM1 counter clock) - 1 SystemCoreClock is set to 72 MHz for Low-density, Medium-density, High-density and Connectivity line devices and to 24 MHz for Low-Density Value line and Medium-Density Value line devices The TIM1 period is 5.8 KHz: TIM1 Frequency = TIM1 counter clock/(ARR + 1) = 24 MHz / 4096 = 5.8KHz KHz TIM1 Channel1 duty cycle = (TIM1_CCR1/ TIM1_ARR)* 100 = 33.33% ----------------------------------------------------------------------- */ TIM_TimeBaseStructure.TIM_Period = 0xFFFF; TIM_TimeBaseStructure.TIM_Prescaler = (uint16_t) (SystemCoreClock / 24000000) - 1; TIM_TimeBaseStructure.TIM_ClockDivision = 0x0; TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure); /* TIM Configuration in PWM Mode */ TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = 0xFFF; TIM_OC1Init(TIM1, &TIM_OCInitStructure); /* TIM1 DMAR Base register and DMA Burst Length Config */ TIM_DMAConfig(TIM1, TIM_DMABase_ARR, TIM_DMABurstLength_3Transfers); /* TIM1 DMA Update enable */ TIM_DMACmd(TIM1, TIM_DMA_Update, ENABLE); /* TIM1 enable */ TIM_Cmd(TIM1, ENABLE); /* TIM1 PWM Outputs Enable */ TIM_CtrlPWMOutputs(TIM1, ENABLE); /* DMA1 Channel5 enable */ DMA_Cmd(DMA1_Channel5, ENABLE); /* Wait until DMA1 Channel5 end of Transfer */ while (!DMA_GetFlagStatus(DMA1_FLAG_TC5)) { } /* Infinite loop */ while(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\r\n", file, line) */ while (1) {} } #endif /** * @} */ /** * @} */ /******************* (C) COPYRIGHT 2011 STMicroelectronics *****END OF FILE****/