/*
 * This file is part of the libopencm3 project.
 *
 * Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
 * Copyright (C) 2011 Stephen Caudle <scaudle@doceme.com>
 * Modified by Fernando Cortes <fermando.corcam@gmail.com>
 * modified by Guillermo Rivera <memogrg@gmail.com>
 *
 * This library is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This library 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/adc.h>
#include <libopencm3/stm32/usart.h>
#include <libopencm3/stm32/gpio.h>

#define LBLUE GPIOE, GPIO8
#define LRED GPIOE, GPIO9
#define LORANGE GPIOE, GPIO10
#define LGREEN GPIOE, GPIO11
#define LBLUE2 GPIOE, GPIO12
#define LRED2 GPIOE, GPIO13
#define LORANGE2 GPIOE, GPIO14
#define LGREEN2 GPIOE, GPIO15

#define LD4 GPIOE, GPIO8
#define LD3 GPIOE, GPIO9
#define LD5 GPIOE, GPIO10
#define LD7 GPIOE, GPIO11
#define LD9 GPIOE, GPIO12
#define LD10 GPIOE, GPIO13
#define LD8 GPIOE, GPIO14
#define LD6 GPIOE, GPIO15


static void adc_setup(void)
{
	//ADC
	rcc_periph_clock_enable(RCC_ADC12);
	rcc_periph_clock_enable(RCC_GPIOA);
	//ADC
	gpio_mode_setup(GPIOA, GPIO_MODE_ANALOG, GPIO_PUPD_NONE, GPIO0);
	gpio_mode_setup(GPIOA, GPIO_MODE_ANALOG, GPIO_PUPD_NONE, GPIO1);
	adc_power_off(ADC1);
	adc_set_clk_prescale(ADC1, ADC_CCR_CKMODE_DIV2);
	adc_set_single_conversion_mode(ADC1);
	adc_disable_external_trigger_regular(ADC1);
	adc_set_right_aligned(ADC1);
	/* We want to read the temperature sensor, so we have to enable it. */
	adc_enable_temperature_sensor();
	adc_set_sample_time_on_all_channels(ADC1, ADC_SMPR_SMP_61DOT5CYC);
	uint8_t channel_array[] = { 1 }; /* ADC1_IN1 (PA0) */
	adc_set_regular_sequence(ADC1, 1, channel_array);
	adc_set_resolution(ADC1, ADC_CFGR1_RES_12_BIT);
	adc_power_on(ADC1);

	/* Wait for ADC starting up. */
	int i;
	for (i = 0; i < 800000; i++)
		__asm__("nop");

}

static void usart_setup(void)
{
	/* Enable clocks for GPIO port A (for GPIO_USART2_TX) and USART2. */
	rcc_periph_clock_enable(RCC_USART2);
	rcc_periph_clock_enable(RCC_GPIOA);

	/* Setup GPIO pin GPIO_USART2_TX/GPIO9 on GPIO port A for transmit. */
	gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO2 | GPIO3);
	gpio_set_af(GPIOA, GPIO_AF7, GPIO2| GPIO3);

	/* Setup UART parameters. */
	usart_set_baudrate(USART2, 115200);
	usart_set_databits(USART2, 8);
	usart_set_stopbits(USART2, USART_STOPBITS_1);
	usart_set_mode(USART2, USART_MODE_TX_RX);
	usart_set_parity(USART2, USART_PARITY_NONE);
	usart_set_flow_control(USART2, USART_FLOWCONTROL_NONE);

	/* Finally enable the USART. */
	usart_enable(USART2);
}

static void gpio_setup(void)
{
	rcc_periph_clock_enable(RCC_GPIOE);
	gpio_mode_setup(GPIOE, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE,
		GPIO8 | GPIO9 | GPIO10 | GPIO11 | GPIO12 | GPIO13 |
		GPIO14 | GPIO15);
}

static void my_usart_print_int(uint32_t usart, int16_t value)
{
	int8_t i;
	int8_t nr_digits = 0;
	char buffer[25];

	if (value < 0) {
		usart_send_blocking(usart, '-');
		value = value * -1;
	}

	if (value == 0) {
		usart_send_blocking(usart, '0');
	}

	while (value > 0) {
		buffer[nr_digits++] = "0123456789"[value % 10];
		value /= 10;
	}

	for (i = nr_digits-1; i >= 0; i--) {
		usart_send_blocking(usart, buffer[i]);
	}

	usart_send_blocking(usart, '\r');
	usart_send_blocking(usart, '\n');
}

static void clock_setup(void)
{
	rcc_clock_setup_hsi(&rcc_hsi_configs[RCC_CLOCK_HSI_64MHZ]);
}


int main(void)
{
	uint16_t temp;

	clock_setup();
	gpio_setup();
	adc_setup();
	usart_setup();

	while (1) {
		adc_start_conversion_regular(ADC1);
		while (!(adc_eoc(ADC1)));
		temp=adc_read_regular(ADC1);
 		gpio_port_write(GPIOE, temp << 4);
		my_usart_print_int(USART2, temp);
	}

	return 0;
}