问题
Im using STM32F429 board and my ultimate goal is to get ADC conversion(set to deliver 2.7Ksps or 2.7 samples every 1ms) using TIM8 trigger, collect 1000 samples in buffer and do DMA transfer every second. I managed to get Timer running, but for some reason ADC conversion is not triggered. Without timer ADC is running well and DMA working (just not every 1ms, but faster).
APB2 Timers clock is 168Mhz. APB2 Peripherals clock is 84Mhz.
TIM8 init function:
void MX_TIM8_Init(void)
{
TIM_ClockConfigTypeDef sClockSourceConfig;
TIM_MasterConfigTypeDef sMasterConfig;
TIM_SlaveConfigTypeDef sSlaveConfig;
TIM_OC_InitTypeDef sConfigOC;
TIM_BreakDeadTimeConfigTypeDef sBreakDeadTimeConfig;
__HAL_RCC_TIM8_CLK_ENABLE();
htim8.Instance = TIM8;
htim8.Init.Prescaler = TIM_CLOCKPRESCALER_DIV8; // 1/(168MHz / 2^8) = 1.5238us
htim8.Init.CounterMode = TIM_COUNTERMODE_UP;
htim8.Init.Period = 655; // 1.5238us * 656 = 0.999ms ~ 1ms
htim8.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim8.Init.RepetitionCounter = 0;
if (HAL_TIM_Base_Init(&htim8) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
HAL_TIM_Base_Start(&htim8);
sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
if (HAL_TIM_ConfigClockSource(&htim8, &sClockSourceConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
sSlaveConfig.SlaveMode = TIM_SLAVEMODE_DISABLE;
sSlaveConfig.InputTrigger = TIM_TS_ITR1;
if (HAL_TIM_SlaveConfigSynchronization(&htim8, &sSlaveConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
if (HAL_TIM_OC_Init(&htim8) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim8, &sMasterConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
sConfigOC.OCMode = TIM_OCMODE_TIMING;
sConfigOC.Pulse = 0;
sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
sConfigOC.OCNPolarity = TIM_OCNPOLARITY_HIGH;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
sConfigOC.OCIdleState = TIM_OCIDLESTATE_RESET;
sConfigOC.OCNIdleState = TIM_OCNIDLESTATE_RESET;
if (HAL_TIM_OC_ConfigChannel(&htim8, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
sBreakDeadTimeConfig.OffStateRunMode = TIM_OSSR_DISABLE;
sBreakDeadTimeConfig.OffStateIDLEMode = TIM_OSSI_DISABLE;
sBreakDeadTimeConfig.LockLevel = TIM_LOCKLEVEL_OFF;
sBreakDeadTimeConfig.DeadTime = 0;
sBreakDeadTimeConfig.BreakState = TIM_BREAK_DISABLE;
sBreakDeadTimeConfig.BreakPolarity = TIM_BREAKPOLARITY_HIGH;
sBreakDeadTimeConfig.AutomaticOutput = TIM_AUTOMATICOUTPUT_DISABLE;
if (HAL_TIMEx_ConfigBreakDeadTime(&htim8, &sBreakDeadTimeConfig) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
}
ADC init function:
void MX_ADC1_Init(void)
{
ADC_ChannelConfTypeDef sConfig;
__HAL_RCC_GPIOA_CLK_ENABLE();
/**Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
*/
hadc1.Instance = ADC1;
hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV2; // 84MHz / 2^6 = 1312.5 KHz
hadc1.Init.Resolution = ADC_RESOLUTION_12B;
hadc1.Init.ScanConvMode = ENABLE;
hadc1.Init.ContinuousConvMode = ENABLE;
hadc1.Init.DiscontinuousConvMode = DISABLE;
hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_RISING;
hadc1.Init.ExternalTrigConv = ADC_EXTERNALTRIGCONV_T8_TRGO;
hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc1.Init.NbrOfConversion = 2;
hadc1.Init.DMAContinuousRequests = ENABLE;
hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
if (HAL_ADC_Init(&hadc1) != HAL_OK) {
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_5;
sConfig.Rank = 1;
sConfig.SamplingTime = ADC_SAMPLETIME_480CYCLES; // 1312.5KHz / 480cyc per sample = 2.7Ksps
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK) {
_Error_Handler(__FILE__, __LINE__);
}
/**Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
*/
sConfig.Channel = ADC_CHANNEL_7;
sConfig.Rank = 2;
sConfig.SamplingTime = ADC_SAMPLETIME_480CYCLES;
if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK) {
_Error_Handler(__FILE__, __LINE__);
}
}
Main code:
int main(void)
{
//MCU Configuration----------------------------------------------------------
// Reset of all peripherals, Initializes the Flash interface and the Systick.
HAL_Init();
// Configure the system clock
SystemClock_Config();
// Initialize all configured peripherals
MX_DMA_Init();
MX_ADC1_Init();
MX_TIM8_Init();
HAL_ADC_Start_DMA(&hadc1, (uint32_t*)ADC_buf, ADC_BUFFER_LENGTH);
DBGMCU->APB2FZ |= (DBGMCU_APB2_FZ_DBG_TIM8_STOP); //Stop timer if code hit a breakpoint
int timerValue = 0;
while (1)
{
timerValue = __HAL_TIM_GET_COUNTER(&htim8);
if (halfConvFlag != false)
{
println ("Half Conversion callback");
halfConvFlag = false;
}
else if (fullConvFlag != false)
{
println ("Full Conversion callback");
fullConvFlag = false;
}
}
}
When debugging, __HAL_TIM_GET_COUNTER gives me the count that proves it is working, but ADC_buf is not collecting any values. What am I missing, clock configurations should be correct 2 channels, 2 samples per ms and timer is close to 1ms. I generated the timer configuration using STM32CubeMX.
来源：https://stackoverflow.com/questions/51631642/adc-conversion-triggered-by-1ms-timer-not-working-stm32f4