Question
STM32F103 + PWM+ DMA + HAL?
Posted on November 26, 2015 at 17:38
I have STM32F103 working on 8MHz.
If I InitPWM on Ch1 Tim3void MX_TIM3_Init(void)
{
TIM_ClockConfigTypeDef sClockSourceConfig;
TIM_MasterConfigTypeDef sMasterConfig;
TIM_OC_InitTypeDef sConfigOC;
htim3.Instance = TIM3;
htim3.Init.Prescaler = 0;
htim3.Init.CounterMode = TIM_COUNTERMODE_UP;
htim3.Init.Period = 9;
htim3.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
HAL_TIM_Base_Init(&htim3);
sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
HAL_TIM_ConfigClockSource(&htim3, &sClockSourceConfig);
HAL_TIM_PWM_Init(&htim3);
sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
HAL_TIMEx_MasterConfigSynchronization(&htim3, &sMasterConfig);
sConfigOC.OCMode = TIM_OCMODE_PWM1;
sConfigOC.Pulse = 1;
sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
HAL_TIM_PWM_ConfigChannel(&htim3, &sConfigOC, TIM_CHANNEL_1);
} and star ti with
HAL_TIM_PWM_Start_IT(&htim3, TIM_CHANNEL_1);
all working OK and output generate 125ns pulse on 800kHz (1.25us)
If replace Start_IT with DMA version
uint32_t pData[1]={6};
HAL_TIM_PWM_Start_DMA(&htim3, TIM_CHANNEL_1,pData,1);
all working OK and output generate 70ns pulse on 800kHz (1.25us),but if use
uint32_t pData[16]={3,3,3,3,3,3,3,3,0,0,0,0,0,0,0,0};
HAL_TIM_PWM_Start_DMA(&htim3, TIM_CHANNEL_1,pData,16); this genreate 375ns its OK but frequency is 400kHz(2,5us)
If I trace and look on reg CCR1 I see
3,0,3,0,3,0,3,0,3,0,3,0,3,0,3,0
What's
wrong
,
what's the problem
?
#he-chose-poorly