text: /****************************************************************************
   * px4/sensors/test_gpio.c
   *
   *  Copyright (C) 2012 PX4 Development Team. All rights reserved.
   *            Lorenz Meier <lm@inf.ethz.ch>
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   * 3. Neither the name NuttX nor the names of its contributors may be
   *    used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
   * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
   * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   ****************************************************************************/
  
  /****************************************************************************
   * Included Files
   ****************************************************************************/
  
  #include <px4_config.h>
  
  #include <sys/types.h>
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <fcntl.h>
  #include <errno.h>
  
  #include <arch/board/board.h>
  
  #include "tests_main.h"
  
  #include <math.h>
  #include <float.h>
  #include <drivers/drv_hrt.h>
  
  
  /****************************************************************************
   * Pre-processor Definitions
   ****************************************************************************/
  
  /****************************************************************************
   * Private Types
   ****************************************************************************/
  
  /****************************************************************************
   * Private Function Prototypes
   ****************************************************************************/
  
  /****************************************************************************
   * Private Data
   ****************************************************************************/
  
  /****************************************************************************
   * Public Data
   ****************************************************************************/
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: test_led
   ****************************************************************************/
  
  int test_uart_send(int argc, char *argv[])
  {
  	/* input handling */
  	char *uart_name = "/dev/ttyS3";
  
  	if (argc > 1) { uart_name = argv[1]; }
  
  	/* assuming NuttShell is on UART1 (/dev/ttyS0) */
  	int test_uart = open(uart_name, O_RDWR | O_NONBLOCK | O_NOCTTY); //
  
  	if (test_uart < 0) {
  		printf("ERROR opening UART %s, aborting..\n", uart_name);
  		return test_uart;
  
  	} else {
  		printf("Writing to UART %s\n", uart_name);
  	}
  
  	char sample_test_uart[25];// = {'S', 'A', 'M', 'P', 'L', 'E', ' ', '\n'};
  
  	int i, n;
  
  	uint64_t start_time = hrt_absolute_time();
  
  	for (i = 0; i < 30000; i++) {
  		n = sprintf(sample_test_uart, "SAMPLE #%d\n", i);
  		write(test_uart, sample_test_uart, n);
  	}
  
  	int interval = hrt_absolute_time() - start_time;
  
  	int bytes = i * sizeof(sample_test_uart);
  
  	printf("Wrote %d bytes in %d ms on UART %s\n", bytes, interval / 1000, uart_name);
  
  	close(test_uart);
  
  	return 0;
  }
  