TIM8,TIM1如何产生dma pwm，其他的TIM2,TIM3,TIM4,TIM5都调通pwm+dma了

yy叶之舞是秋的讯息 · 发表于 2021-6-18 10:47:06

附上代码。求助原子哥@正点原子
void Timer8_init(void)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
DMA_InitTypeDef DMA_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE);
/* GPIOC Configuration: TIM8 Channel 4 as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOC, &GPIO_InitStructure);

RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, ENABLE);
/* Compute the prescaler value */
//PrescalerValue = (uint16_t) (SystemCoreClock / 24000000) - 1;
/* Time base configuration */
TIM_TimeBaseStructure.TIM_Period = 90-1; // 800kHz
TIM_TimeBaseStructure.TIM_Prescaler = 0;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure);

/* PWM1 Mode configuration: Channel4 */
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OC4Init(TIM8, &TIM_OCInitStructure);

TIM_CtrlPWMOutputs(TIM8, ENABLE); //TIMx: where x can be 1, 8, 15, 16 or 17 to select the TIMx peripheral.
/* configure DMA */
/* DMA clock enable */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA2, ENABLE);

/* DMA2 Channel1 Config for PWM1 by TIM8_CH1*/
DMA_DeInit(DMA2_Channel1);

DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)TIM8_CCR4_Address; // physical address of Timer 3 CCR1
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)LED_BYTE_Buffer[5];//LED_BYTE_Buffer[0];//LED1_BYTE_Buffer;// // this is the buffer memory
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST; // data shifted from memory to peripheral
DMA_InitStructure.DMA_BufferSize = 42;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; // automatically increase buffer index
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; // stop DMA feed after buffer size is reached
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;

DMA_Init(DMA2_Channel1, &DMA_InitStructure);

TIM_DMACmd(TIM8, TIM_DMA_Update, ENABLE);
}