gadget-tester/adc.c

/*
 *
 * Copyright (c) 2019
 * Author: Daniele Lacamera <root@danielinux.net>
 * GPL2.0
 */
#include <stdint.h>
#include "adc.h"
#include "system.h"


int adc_init(void)
{
    int i;
    uint32_t val;
    /* Enable clock */
    APB2_CLOCK_ER |= ADC1_APB2_CLOCK_ER_VAL;

    /* Power off */
    ADC1_CR2 &= ~(ADC_CR2_EN);

    /* Set common clock prescaler */
    ADC_COM_CCR &= ~(0x03 << 16);

    /* Disable scan mode */
    ADC1_CR1 &= ~(ADC_CR1_SCAN);

    /* Set one-shot (disable continuous mode) */
    ADC1_CR2 &= ~(ADC_CR2_CONT);

    /* Set sample time for all channels */
    val = ADC1_SMPR1;

    for (i = 0; i < 10; i++) {
            val |= ADC_SMPR_SMP_480CYC << (i * 3);
    ADC1_SMPR1 = val;
    val = ADC1_SMPR2;
    for (i = 10; i < 18; i++) 
            val |= ADC_SMPR_SMP_480CYC << ((i-10) * 3);
    }
    ADC1_SMPR2 = val;
    ADC1_CR2 &= ~(ADC_CR2_EN);
    return 0;
}

void adc_pin_val(uint32_t ch, uint16_t *val)
{
        ADC1_SQR3 = ch;
        ADC1_CR2 |= ADC_CR2_EN;
        ADC1_CR2 |= ADC_CR2_SWSTART;
        while (ADC1_CR2 & ADC_CR2_SWSTART);;
        while ((ADC1_SR & ADC_SR_EOC) == 0);;
        *val= ADC1_DR;
        printf("Channel %d val %hu\r\n", ch, *val);
        ADC1_SQR3 = 0;
}