1 files changed, 264 insertions, 0 deletions
diff --git a/src/drivers/hott/hott_telemetry/hott_telemetry.cpp b/src/drivers/hott/hott_telemetry/hott_telemetry.cpp
new file mode 100644
index 000000000..d293f9954
--- /dev/null
+++ b/src/drivers/hott/hott_telemetry/hott_telemetry.cpp
@@ -0,0 +1,264 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2012, 2013 PX4 Development Team. All rights reserved.
+ *   Author: Simon Wilks <sjwilks@gmail.com>
+ *
+ * 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 hott_telemetry_main.c
+ * @author Simon Wilks <sjwilks@gmail.com>
+ *
+ * Graupner HoTT Telemetry implementation.
+ *
+ * The HoTT receiver polls each device at a regular interval at which point
+ * a data packet can be returned if necessary.
+ *
+ */
+
+#include <fcntl.h>
+#include <nuttx/config.h>
+#include <poll.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <systemlib/err.h>
+#include <systemlib/systemlib.h>
+
+#include "../comms.h"
+#include "../messages.h"
+
+#define DEFAULT_UART "/dev/ttyS0";		/**< USART1 */
+
+/* Oddly, ERROR is not defined for C++ */
+#ifdef ERROR
+# undef ERROR
+#endif
+static const int ERROR = -1;
+
+static int thread_should_exit = false;		/**< Deamon exit flag */
+static int thread_running = false;		/**< Deamon status flag */
+static int deamon_task;				/**< Handle of deamon task / thread */
+static const char daemon_name[] = "hott_telemetry";
+static const char commandline_usage[] = "usage: hott_telemetry start|status|stop [-d <device>]";
+
+/**
+ * Deamon management function.
+ */
+extern "C" __EXPORT int hott_telemetry_main(int argc, char *argv[]);
+
+/**
+ * Mainloop of daemon.
+ */
+int hott_telemetry_thread_main(int argc, char *argv[]);
+
+static int recv_req_id(int uart, uint8_t *id);
+static int send_data(int uart, uint8_t *buffer, size_t size);
+
+int
+recv_req_id(int uart, uint8_t *id)
+{
+	static const int timeout_ms = 1000;  // TODO make it a define
+
+	uint8_t mode;
+	
+	struct pollfd fds;
+	fds.fd = uart;
+	fds.events = POLLIN;
+
+	if (poll(&fds, 1, timeout_ms) > 0) {
+		/* Get the mode: binary or text  */
+		read(uart, &mode, sizeof(mode));
+
+		/* if we have a binary mode request */
+		if (mode != BINARY_MODE_REQUEST_ID) {
+			return ERROR;
+		}
+
+		/* Read the device ID being polled */
+		read(uart, id, sizeof(*id));
+	} else {
+		warnx("UART timeout on TX/RX port");
+		return ERROR;
+	}
+
+	return OK;
+}
+
+int
+send_data(int uart, uint8_t *buffer, size_t size)
+{
+	usleep(POST_READ_DELAY_IN_USECS);
+
+	uint16_t checksum = 0;
+	for (size_t i = 0; i < size; i++) {
+		if (i == size - 1) {
+			/* Set the checksum: the first uint8_t is taken as the checksum. */
+			buffer[i] = checksum & 0xff;
+
+		} else {
+			checksum += buffer[i];
+		}
+
+		write(uart, &buffer[i], sizeof(buffer[i]));
+
+		/* Sleep before sending the next byte. */
+		usleep(POST_WRITE_DELAY_IN_USECS);
+	}
+
+	/* A hack the reads out what was written so the next read from the receiver doesn't get it. */
+	/* TODO: Fix this!! */
+	uint8_t dummy[size];
+	read(uart, &dummy, size);
+
+	return OK;
+}
+
+int
+hott_telemetry_thread_main(int argc, char *argv[])
+{
+	warnx("starting");
+
+	thread_running = true;
+
+	const char *device = DEFAULT_UART;
+
+	/* read commandline arguments */
+	for (int i = 0; i < argc && argv[i]; i++) {
+		if (strcmp(argv[i], "-d") == 0 || strcmp(argv[i], "--device") == 0) { //device set
+			if (argc > i + 1) {
+				device = argv[i + 1];
+
+			} else {
+				thread_running = false;
+				errx(1, "missing parameter to -d\n%s", commandline_usage);
+			}
+		}
+	}
+
+	/* enable UART, writes potentially an empty buffer, but multiplexing is disabled */
+	const int uart = open_uart(device);
+	if (uart < 0) {
+		errx(1, "Failed opening HoTT UART, exiting.");
+		thread_running = false;
+	}
+
+	init_sub_messages();
+
+	uint8_t buffer[MAX_MESSAGE_BUFFER_SIZE];
+	size_t size = 0;
+	uint8_t id = 0;
+	bool connected = true;
+	while (!thread_should_exit) {
+		// Listen for and serve poll from the receiver.
+		if (recv_req_id(uart, &id) == OK) {
+			if (!connected) {
+				connected = true;
+				warnx("OK");
+			}
+
+			switch (id) {
+			case EAM_SENSOR_ID:
+				build_eam_response(buffer, &size);
+				break;
+			case GAM_SENSOR_ID:
+				build_gam_response(buffer, &size);
+				break;
+			case GPS_SENSOR_ID:
+				build_gps_response(buffer, &size);
+				break;
+
+			default:
+				continue;	// Not a module we support.
+			}
+
+			send_data(uart, buffer, size);
+		} else {
+			connected = false;
+			warnx("syncing");
+		}
+	}
+
+	warnx("exiting");
+
+	close(uart);
+
+	thread_running = false;
+
+	return 0;
+}
+
+/**
+ * Process command line arguments and start the daemon.
+ */
+int
+hott_telemetry_main(int argc, char *argv[])
+{
+	if (argc < 1) {
+		errx(1, "missing command\n%s", commandline_usage);
+	}
+
+	if (!strcmp(argv[1], "start")) {
+
+		if (thread_running) {
+			warnx("deamon already running");
+			exit(0);
+		}
+
+		thread_should_exit = false;
+		deamon_task = task_spawn_cmd(daemon_name,
+					 SCHED_DEFAULT,
+					 SCHED_PRIORITY_DEFAULT,
+					 2048,
+					 hott_telemetry_thread_main,
+					 (argv) ? (const char **)&argv[2] : (const char **)NULL);
+		exit(0);
+	}
+
+	if (!strcmp(argv[1], "stop")) {
+		thread_should_exit = true;
+		exit(0);
+	}
+
+	if (!strcmp(argv[1], "status")) {
+		if (thread_running) {
+			warnx("daemon is running");
+
+		} else {
+			warnx("daemon not started");
+		}
+
+		exit(0);
+	}
+
+	errx(1, "unrecognized command\n%s", commandline_usage);
+}