2022-03-10 11:04:14 +03:00

73 lines
2.4 KiB
C

/*
* sharp.c - functions for Sharp 2Y0A02 distance meter
*
* Copyright 2015 Edward V. Emelianov <eddy@sao.ru, edward.emelianoff@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#include "sharp.h"
#include "main.h"
int AWD_flag = 0;
uint16_t AWD_value = 0;
void init_sharp_sensor(){
// Make sure the ADC doesn't run during config
adc_off(ADC1);
// enable ADC & PA0 clocking
rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_ADC1EN | RCC_APB2ENR_IOPAEN);
rcc_set_adcpre(RCC_CFGR_ADCPRE_PCLK2_DIV4);
gpio_set_mode(GPIOA, GPIO_MODE_INPUT, GPIO_CNF_INPUT_ANALOG, GPIO0);
// set sample time: 239.5 cycles for better results
ADC1_SMPR2 = 7;
// continuous conv, enable
ADC1_CR2 = ADC_CR2_CONT | ADC_CR2_ADON;
// reset calibration registers & start calibration
ADC1_CR2 |= ADC_CR2_RSTCAL;
while(ADC1_CR2 & ADC_CR2_RSTCAL); // wait for registers reset
ADC1_CR2 |= ADC_CR2_CAL;
while(ADC1_CR2 & ADC_CR2_CAL); // wait for calibration ends
// set threshold limits
ADC1_HTR = ADC_WDG_HIGH;
ADC1_LTR = ADC_WDG_LOW;
// enable analog watchdog on single regular channel 0 & enable interrupt
ADC1_CR1 = ADC_CR1_AWDEN | ADC_CR1_AWDSGL | ADC_CR1_AWDIE;
nvic_enable_irq(NVIC_ADC1_2_IRQ);
ADC1_CR2 |= ADC_CR2_SWSTART;
// start - to do it we need set ADC_CR2_ADON again!
ADC1_CR2 |= ADC_CR2_ADON;
DBG("ADC started\n");
}
void adc1_2_isr(){
AWD_value = ADC1_DR;
if(ADC1_SR & ADC_SR_AWD){ // analog watchdog event
AWD_flag = 1;
// ADC1_CR1 &= ~(ADC_CR1_AWDIE | ADC_CR1_AWDEN);
// nvic_disable_irq(NVIC_ADC1_2_IRQ);
if(AWD_value >= ADC_WDG_HIGH){ // high threshold
ADC1_HTR = 0x0fff; // remove high threshold, only wait for LOW
ADC1_LTR = ADC_WDG_LOW;
}else{
ADC1_HTR = ADC_WDG_HIGH;
ADC1_LTR = 0;
}
//ADC1_CR1 |= ADC_CR1_AWDIE;
}
ADC1_SR = 0;
}