/*
 * This file is part of the libopencm3 project.
 *
 * Copyright (C) 2011 Gareth McMullin <gareth@blacksphere.co.nz>
 * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@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/lm4f/systemcontrol.h>
#include <libopencm3/lm4f/gpio.h>
#include <libopencm3/lm4f/uart.h>

static void uart_setup(void)
{
	/* Enable GPIOA in run mode. */
	periph_clock_enable(RCC_GPIOA);
	/* Mux PA0 and PA1 to UART0 (alternate function 1) */
	gpio_set_af(GPIOA, 1, GPIO0 | GPIO1);

	/* Enable the UART clock */
	periph_clock_enable(RCC_UART0);
	/* We need a brief delay before we can access UART config registers */
	__asm__("nop");
	/* Disable the UART while we mess with its setings */
	uart_disable(UART0);
	/* Configure the UART clock source as precision internal oscillator */
	uart_clock_from_piosc(UART0);
	/* Set communication parameters */
	uart_set_baudrate(UART0, 921600);
	uart_set_databits(UART0, 8);
	uart_set_parity(UART0, UART_PARITY_NONE);
	uart_set_stopbits(UART0, 1);
	/* Now that we're done messing with the settings, enable the UART */
	uart_enable(UART0);

}

int main(void)
{
	uint8_t rx;

	gpio_enable_ahb_aperture();
	uart_setup();

	/*
	 * Yes, it's that simple !
	 */
	while(1) {
		rx = uart_recv_blocking(UART0);
		uart_send_blocking(UART0, rx);
	}

	return 0;
}