/**************************************************************************** * * Copyright (C) 2012 PX4 Development Team. All rights reserved. * Author: Lorenz Meier * * 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 PX4 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. * ****************************************************************************/ /** * @file delay_test.c * * Simple but effective delay test using leds and a scope to measure * communication delays end-to-end accurately. * * @author Lorenz Meier */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include __EXPORT int delay_test_main(int argc, char *argv[]); static int led_on(int leds, int led); static int led_off(int leds, int led); int delay_test_main(int argc, char *argv[]) { bool vicon_msg = false; bool command_msg = false; if (argc > 1 && !strcmp(argv[1], "--help")) { warnx("usage: delay_test [vicon] [command]\n"); exit(1); } if (argc > 1 && !strcmp(argv[1], "vicon")) { vicon_msg = true; } if (argc > 1 && !strcmp(argv[1], "command")) { command_msg = true; } int buzzer = open("/dev/tone_alarm", O_WRONLY); int leds = open(LED_DEVICE_PATH, 0); /* prepare use of amber led */ led_off(leds, LED_AMBER); int topic; /* subscribe to topic */ if (vicon_msg) { topic = orb_subscribe(ORB_ID(vehicle_vicon_position)); } else if (command_msg) { topic = orb_subscribe(ORB_ID(vehicle_command)); } else { errx(1, "No topic selected for delay test, use --help for a list of topics."); } const int testcount = 20; warnx("running %d iterations..\n", testcount); struct pollfd fds[1]; fds[0].fd = topic; fds[0].events = POLLIN; /* display and sound error */ for (int i = 0; i < testcount; i++) { /* wait for topic */ int ret = poll(&fds[0], 1, 2000); /* this would be bad... */ if (ret < 0) { warnx("poll error %d", errno); usleep(1000000); continue; } /* do we have a topic update? */ if (fds[0].revents & POLLIN) { /* copy object to disable poll ready state */ if (vicon_msg) { struct vehicle_vicon_position_s vicon_position; orb_copy(ORB_ID(vehicle_vicon_position), topic, &vicon_position); } else if (command_msg) { struct vehicle_command_s vehicle_command; orb_copy(ORB_ID(vehicle_command), topic, &vehicle_command); } led_on(leds, LED_AMBER); ioctl(buzzer, TONE_SET_ALARM, 4); /* keep led on for 50 ms to make it barely visible */ usleep(50000); led_off(leds, LED_AMBER); } } /* stop alarm */ ioctl(buzzer, TONE_SET_ALARM, 0); /* switch on leds */ led_on(leds, LED_BLUE); led_on(leds, LED_AMBER); exit(0); } static int led_off(int leds, int led) { return ioctl(leds, LED_OFF, led); } static int led_on(int leds, int led) { return ioctl(leds, LED_ON, led); }