libopencm3/examples/stm32/f2/jobygps/usart_printf/usart_printf.c

/*
 * This file is part of the libopencm3 project.
 *
 * Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>,
 * Copyright (C) 2011 Piotr Esden-Tempski <piotr@esden.net>
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include <libopencm3/stm32/f2/gpio.h>
#include <libopencm3/stm32/usart.h>
#include <libopencm3/stm32/nvic.h>
#include <libopencm3/stm32/f2/rcc.h>

#include <stdio.h>
#include <errno.h>

void clock_setup(void)
{

#warning "This code has to call some kind of rcc clock setup function!!!"

	//rcc_clock_setup_in_hse_8mhz_out_72mhz();

	/* Enable GPIOA clock (for LED GPIOs). */
	//rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_IOPCEN);

	/* Enable clocks for GPIO port A (for GPIO_USART1_TX) and USART1. */
	// rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_IOPAEN |
	// 			RCC_APB2ENR_AFIOEN | RCC_APB2ENR_USART1EN);
	RCC_APB2ENR |= RCC_APB2ENR_USART1EN;
	RCC_AHB1ENR |= RCC_AHB1ENR_IOPCEN | RCC_AHB1ENR_IOPAEN;
}

void usart_setup(void)
{
	gpio_mode_setup(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO9);
	gpio_set_af(GPIOA, GPIO_AF7, GPIO9 | GPIO10);

	/* Setup UART parameters. */
	usart_set_baudrate(USART1, 9600);
	usart_set_databits(USART1, 8);
	usart_set_stopbits(USART1, USART_STOPBITS_1);
	usart_set_parity(USART1, USART_PARITY_NONE);
	usart_set_flow_control(USART1, USART_FLOWCONTROL_NONE);
	usart_set_mode(USART1, USART_MODE_TX);

	/* Finally enable the USART. */
	usart_enable(USART1);
}

void gpio_setup(void)
{
	gpio_set(GPIOC, GPIO3);

	/* Setup GPIO6 and 7 (in GPIO port A) for LED use. */
	gpio_mode_setup(GPIOC, GPIO_MODE_OUTPUT, GPIO_MODE_OUTPUT, GPIO3);
}

int _write(int file, char *ptr, int len)
{
	int i;

	if (file == 1) {
		for (i = 0; i < len; i++)
			usart_send_blocking(USART1, ptr[i]);
		return i;
	}

	errno = EIO;
	return -1;
}

int main(void)
{
	int counter = 0;
	float fcounter = 0.0;
	double dcounter = 0.0;

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

	/*
	 * Write Hello World an integer, float and double all over
	 * again while incrementing the numbers.
	 */
	while (1) {
		gpio_toggle(GPIOC, GPIO3);
		printf("Hello World! %i %f %f\r\n", counter, fcounter,
		       dcounter);
		counter++;
		fcounter += 0.01;
		dcounter += 0.01;
	}

	return 0;
}