Posted on March 28, 2017 at 12:59I'm trying to use stm32f301 comparator 2, but the output is always 0 no matter if the two inputs are higher or lower. I guess the configuration is wrong.
The main code is here. Thanks for the help in advance!
void ConfigureComp2(vod)
{
GPIO_InitTypeDef GPIO_InitStruct;
//init A7, A2 as analog
GPIO_InitStruct.Pin = GPIO_PIN_7;
GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
GPIO_InitStruct.Pull = GPIO_PULLDOWN;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
GPIO_InitStruct.Pin = GPIO_PIN_2;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
RCC->AHBENR |= RCC_AHBENR_GPIOAEN;
RCC->APB2ENR |= RCC_APB2ENR_SYSCFGEN;
//COMP2->CSR |= COMP_CSR_COMPxOUTSEL_0;
printf('after reset out %d\n', COMP2->CSR);
COMP2->CSR |= COMP_CSR_COMPxINSEL_2;
COMP2->CSR |= COMP_CSR_COMPxINSEL_1;
printf('after input selection out %d\n', COMP2->CSR);
//COMP2->CSR |= COMP_CSR_COMPxPOL;
//printf('after pol out %d\n', COMP2->CSR);
COMP2->CSR |= COMP_CSR_COMPxEN;
printf('after enable, out %d\n', COMP2->CSR);
for (int i=0; i<5; i++)
{
printf('comp2 i %d out %d\n', i, COMP2->CSR);
printf('comp2 i %d out %d\n', i, COMP2->CSR & COMP2_CSR_COMP2OUT);
}
}
