STM32F746IGT - Cannot trigger ADC conversion with Timer 4

[RZieb]

Hello,

I'm working on hobby project using STM32F746IGT. I wrote ADC init sequence but cannot get it working properly. Timer 4 reloads at given period and It's interrupt is called properly. ADC starts conversion after setting SWSTART bit manually but I cannot make Timer4 to trigger ADC1.

Please help 🙂

void adc_init( void )
{
	RCC -> APB2ENR |= RCC_APB2ENR_ADC1EN;
	RCC -> APB1ENR |= RCC_APB1ENR_TIM4EN;
	RCC -> AHB1ENR |= RCC_AHB1ENR_GPIOAEN | RCC_AHB1ENR_GPIOHEN;
 
	gpio_pin_cfg(GPIOA, 7, GPIO_ANALOG);
 
	// Timer 4 TRGO
	// Max 36 MHz @ 3.3V
	ADC->CCR = ADC_CCR_ADCPRE_0 | ADC_CCR_ADCPRE_1;
 
	ADC1->CR2 =  ADC_CR2_EXTEN_0 | ADC_CR2_EXTSEL_3 | ADC_CR2_EXTSEL_2 |  ADC_CR2_ADON;
	ADC1->CR1  = ADC_CR1_SCAN | ADC_CR1_DISCEN | ADC_CR1_EOCIE;
	ADC1->SQR1  = 0;  				// 1 regular conversion
	ADC1->SQR3  = (7 << 0);    		// 1st conv IN7
	ADC1->SMPR2 = (0b001 << (7*3)); // IN7 112 cycles
	NVIC_EnableIRQ( ADC_IRQn );
	NVIC_EnableIRQ( TIM4_IRQn );
 
	ADC1->CR2 |= ADC_CR2_SWSTART;
 
	// Sampling 16000 Hz
	//
	TIM4 -> ARR = 125 - 1;
	// 500ns tick
	//
	TIM4 -> PSC = 216/2/2 - 1;
	TIM4 -> CNT = 0;
	TIM4 -> EGR = TIM_EGR_UG;
	TIM4 -> CR2 = TIM_CR2_MMS_1;
	TIM4 -> DIER = TIM_DIER_UIE;
	TIM4 -> CR1 |= TIM_CR1_CEN;
}
 
 
void ADC_IRQHandler(void)
{
	ADC1->SR = 0;
	ADC->CSR = 0;
	//static uint8_t val = 0;
	double in = (double)(ADC1->DR-2048.0)/4096.0;
	in++;
}
 
void TIM4_IRQHandler(void)
{
	TIM4->SR = 0;
}

[Amel NASRI]

Thanks @Community member​ for coming back to this discussion. As confirmed here, issue is tracked internally.

-Amel

[waclawek.jan]

Thanks, Amel.

Jan