添加pacecat_lds50c驱动,未完成

src/drivers/distance_sensor/CMakeLists.txt

@@ -50,3 +50,4 @@ add_subdirectory(vl53l0x)
 add_subdirectory(vl53l1x)
 add_subdirectory(gy_us42)
 add_subdirectory(nanoradar_mr72)
+add_subdirectory(pacecat_lds50c)

src/drivers/distance_sensor/pacecat_lds50c/CMakeLists.txt

@@ -0,0 +1,45 @@
+############################################################################
+#
+#   Copyright (c) 2017-2019 PX4 Development Team. All rights reserved.
+#
+# 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.
+#
+############################################################################
+px4_add_module(
+	MODULE drivers__pacecat_lds50c
+	MAIN pacecat_lds50c
+	SRCS
+		pacecat_lds50c.cpp
+		pacecat_lds50c.hpp
+		pacecat_lds50c_main.cpp
+		pacecat_lds50c_parser.cpp
+	MODULE_CONFIG
+		module.yaml
+	DEPENDS
+		drivers_rangefinder
+	)

src/drivers/distance_sensor/pacecat_lds50c/module.yaml

@@ -0,0 +1,7 @@
+module_name: Benewake pacecat_lds50c lidar
+serial_config:
+    - command: pacecat_lds50c start -d ${SERIAL_DEV}
+      port_config_param:
+        name: SENS_PACEC_CFG
+        group: Sensors
+

src/drivers/distance_sensor/pacecat_lds50c/pacecat_lds50c.cpp

@@ -0,0 +1,269 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2017-2019, 2021 PX4 Development Team. All rights reserved.
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+#include "pacecat_lds50c.hpp"
+
+#include <lib/drivers/device/Device.hpp>
+#include <fcntl.h>
+
+PACECAT_LDS50C::PACECAT_LDS50C(const char *port, uint8_t rotation) :
+	ScheduledWorkItem(MODULE_NAME, px4::serial_port_to_wq(port)),
+	_px4_rangefinder(0, rotation)
+{
+	// store port name
+	strncpy(_port, port, sizeof(_port) - 1);
+
+	// enforce null termination
+	_port[sizeof(_port) - 1] = '\0';
+
+	device::Device::DeviceId device_id;
+	device_id.devid_s.devtype = DRV_DIST_DEVTYPE_PACECAT_LDS50C;
+	device_id.devid_s.bus_type = device::Device::DeviceBusType_SERIAL;
+
+	uint8_t bus_num = atoi(&_port[strlen(_port) - 1]); // Assuming '/dev/ttySx'
+
+	if (bus_num < 10) {
+		device_id.devid_s.bus = bus_num;
+	}
+
+	_px4_rangefinder.set_device_id(device_id.devid);
+	_px4_rangefinder.set_rangefinder_type(distance_sensor_s::MAV_DISTANCE_SENSOR_LASER);
+}
+
+PACECAT_LDS50C::~PACECAT_LDS50C()
+{
+	// make sure we are truly inactive
+	stop();
+
+	perf_free(_sample_perf);
+	perf_free(_comms_errors);
+}
+
+int
+PACECAT_LDS50C::init()
+{
+
+	// PACECAT_LDS50C (50m, 10 Hz)
+	// Note:
+	// Sensor specification shows 0.15m as minimum
+	_px4_rangefinder.set_min_distance(0.15f);
+	_px4_rangefinder.set_max_distance(50.0f);
+	_px4_rangefinder.set_vfov(math::radians(1.f));
+	_px4_rangefinder.set_hfov(math::radians(360.f));
+
+	// status
+	int ret = 0;
+
+	do { // create a scope to handle exit conditions using break
+
+		// open fd
+		_fd = ::open(_port, O_RDWR | O_NOCTTY);
+
+		if (_fd < 0) {
+			PX4_ERR("Error opening fd");
+			return -1;
+		}
+
+		// baudrate 115200, 8 bits, no parity, 1 stop bit
+		unsigned speed = B500000;
+		termios uart_config{};
+		int termios_state{};
+
+		tcgetattr(_fd, &uart_config);
+
+		// clear ONLCR flag (which appends a CR for every LF)
+		uart_config.c_oflag &= ~ONLCR;
+
+		// set baud rate
+		if ((termios_state = cfsetispeed(&uart_config, speed)) < 0) {
+			PX4_ERR("CFG: %d ISPD", termios_state);
+			ret = -1;
+			break;
+		}
+
+		if ((termios_state = cfsetospeed(&uart_config, speed)) < 0) {
+			PX4_ERR("CFG: %d OSPD\n", termios_state);
+			ret = -1;
+			break;
+		}
+
+		if ((termios_state = tcsetattr(_fd, TCSANOW, &uart_config)) < 0) {
+			PX4_ERR("baud %d ATTR", termios_state);
+			ret = -1;
+			break;
+		}
+
+		uart_config.c_cflag |= (CLOCAL | CREAD);	// ignore modem controls
+		uart_config.c_cflag &= ~CSIZE;
+		uart_config.c_cflag |= CS8;			// 8-bit characters
+		uart_config.c_cflag &= ~PARENB;			// no parity bit
+		uart_config.c_cflag &= ~CSTOPB;			// only need 1 stop bit
+		uart_config.c_cflag &= ~CRTSCTS;		// no hardware flowcontrol
+
+		// setup for non-canonical mode
+		uart_config.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
+		uart_config.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+		uart_config.c_oflag &= ~OPOST;
+
+		// fetch bytes as they become available
+		uart_config.c_cc[VMIN] = 1;
+		uart_config.c_cc[VTIME] = 1;
+
+		if (_fd < 0) {
+			PX4_ERR("FAIL: pacecat_lds50c fd");
+			ret = -1;
+			break;
+		}
+	} while (0);
+
+	// close the fd
+	::close(_fd);
+	_fd = -1;
+
+	if (ret == PX4_OK) {
+		start();
+	}
+
+	return ret;
+}
+
+int
+PACECAT_LDS50C::collect()
+{
+	perf_begin(_sample_perf);
+
+	// clear buffer if last read was too long ago
+	int64_t read_elapsed = hrt_elapsed_time(&_last_read);
+
+	char readbuf[sizeof(_linebuf)] {};
+	unsigned readlen = sizeof(readbuf) - 1;
+
+	int ret = 0;
+	float distance_m = -1.0f;
+
+	// Check the number of bytes available in the buffer
+	int bytes_available = 0;
+	::ioctl(_fd, FIONREAD, (unsigned long)&bytes_available);
+
+	if (!bytes_available) {
+		perf_end(_sample_perf);
+		return 0;
+	}
+
+	// parse entire buffer
+	const hrt_abstime timestamp_sample = hrt_absolute_time();
+
+	do {
+		// read from the sensor (uart buffer)
+		ret = ::read(_fd, &readbuf[0], readlen);
+
+		if (ret < 0) {
+			PX4_ERR("read err: %d", ret);
+			perf_count(_comms_errors);
+			perf_end(_sample_perf);
+
+			// only throw an error if we time out
+			if (read_elapsed > (kCONVERSIONINTERVAL * 2)) {
+				/* flush anything in RX buffer */
+				tcflush(_fd, TCIFLUSH);
+				return ret;
+
+			} else {
+				return -EAGAIN;
+			}
+		}
+
+		_last_read = hrt_absolute_time();
+
+		// parse buffer
+		for (int i = 0; i < ret; i++) {
+			pacecat_lds50c_parse(readbuf[i], _linebuf, &_linebuf_index, &_parse_state, &distance_m);
+		}
+
+		// bytes left to parse
+		bytes_available -= ret;
+
+	} while (bytes_available > 0);
+
+	// no valid measurement after parsing buffer
+	if (distance_m < 0.0f) {
+		perf_end(_sample_perf);
+		return -EAGAIN;
+	}
+
+	// publish most recent valid measurement from buffer
+	_px4_rangefinder.update(timestamp_sample, distance_m);
+
+	perf_end(_sample_perf);
+
+	return PX4_OK;
+}
+
+void
+PACECAT_LDS50C::start()
+{
+	// schedule a cycle to start things (the sensor sends at 100Hz, but we run a bit faster to avoid missing data)
+	ScheduleOnInterval(7_ms);
+}
+
+void
+PACECAT_LDS50C::stop()
+{
+	ScheduleClear();
+}
+
+void
+PACECAT_LDS50C::Run()
+{
+	// fds initialized?
+	if (_fd < 0) {
+		// open fd
+		_fd = ::open(_port, O_RDWR | O_NOCTTY);
+	}
+
+	// perform collection
+	if (collect() == -EAGAIN) {
+		// reschedule to grab the missing bits, time to transmit 9 bytes @ 115200 bps
+		ScheduleClear();
+		ScheduleOnInterval(7_ms, 87 * 9);
+		return;
+	}
+}
+
+void
+PACECAT_LDS50C::print_info()
+{
+	printf("Using port '%s'\n", _port);
+	perf_print_counter(_sample_perf);
+	perf_print_counter(_comms_errors);
+}

src/drivers/distance_sensor/pacecat_lds50c/pacecat_lds50c.hpp

@@ -0,0 +1,101 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2017-2019, 2021 PX4 Development Team. All rights reserved.
+ *
+ * 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 PACECAT_LDS50C.cpp
+ * @author Lorenz Meier <lm@inf.ethz.ch>
+ * @author Greg Hulands
+ * @author Ayush Gaud <ayush.gaud@gmail.com>
+ * @author Christoph Tobler <christoph@px4.io>
+ * @author Mohammed Kabir <mhkabir@mit.edu>
+ *
+ * Driver for the Benewake PACECAT_LDS50C laser rangefinder series
+ */
+
+#pragma once
+
+#include <termios.h>
+
+#include <drivers/drv_hrt.h>
+#include <lib/perf/perf_counter.h>
+#include <px4_platform_common/px4_config.h>
+#include <px4_platform_common/module.h>
+#include <px4_platform_common/px4_work_queue/ScheduledWorkItem.hpp>
+#include <lib/drivers/rangefinder/PX4Rangefinder.hpp>
+#include <uORB/topics/distance_sensor.h>
+
+#include "pacecat_lds50c_parser.h"
+
+#define PACECAT_LDS50C_DEFAULT_PORT	"/dev/ttyS3"
+#define BUF_LEN 1000
+
+using namespace time_literals;
+
+class PACECAT_LDS50C : public px4::ScheduledWorkItem
+{
+public:
+	PACECAT_LDS50C(const char *port, uint8_t rotation = distance_sensor_s::ROTATION_FORWARD_FACING);
+	virtual ~PACECAT_LDS50C();
+
+	int init();
+
+	void print_info();
+
+private:
+
+	int collect();
+
+	void Run() override;
+
+	void start();
+	void stop();
+
+	PX4Rangefinder	_px4_rangefinder;
+
+	PACECAT_LDS50C_PARSE_STATE _parse_state {PACECAT_LDS50C_PARSE_STATE::STATE0_UNSYNC};
+
+	char _linebuf[BUF_LEN] {};
+	char _port[20] {};
+
+	static constexpr int kCONVERSIONINTERVAL{9_ms};
+
+	int _fd{-1};
+
+	unsigned int _linebuf_index{0};
+
+	hrt_abstime _last_read{0};
+
+	perf_counter_t _comms_errors{perf_alloc(PC_COUNT, MODULE_NAME": com_err")};
+	perf_counter_t _sample_perf{perf_alloc(PC_ELAPSED, MODULE_NAME": read")};
+
+};

src/drivers/distance_sensor/pacecat_lds50c/pacecat_lds50c_main.cpp

@@ -0,0 +1,188 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2017-2019 PX4 Development Team. All rights reserved.
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+#include "pacecat_lds50c.hpp"
+
+#include <px4_platform_common/getopt.h>
+
+/**
+ * Local functions in support of the shell command.
+ */
+namespace pacecat
+{
+
+pacecat_lds50c	*g_dev{nullptr};
+
+int start(const char *port, uint8_t rotation);
+int status();
+int stop();
+int usage();
+
+int
+start(const char *port, uint8_t rotation)
+{
+	if (g_dev != nullptr) {
+		PX4_ERR("already started");
+		return PX4_OK;
+	}
+
+	// Instantiate the driver.
+	g_dev = new pacecat_lds50c(port, rotation);
+
+	if (g_dev == nullptr) {
+		PX4_ERR("driver start failed");
+		return PX4_ERROR;
+	}
+
+	if (OK != g_dev->init()) {
+		PX4_ERR("driver start failed");
+		delete g_dev;
+		g_dev = nullptr;
+		return PX4_ERROR;
+	}
+
+	return PX4_OK;
+}
+
+int
+status()
+{
+	if (g_dev == nullptr) {
+		PX4_ERR("driver not running");
+		return 1;
+	}
+
+	printf("state @ %p\n", g_dev);
+	g_dev->print_info();
+
+	return 0;
+}
+
+int stop()
+{
+	if (g_dev != nullptr) {
+		PX4_INFO("stopping driver");
+		delete g_dev;
+		g_dev = nullptr;
+		PX4_INFO("driver stopped");
+
+	} else {
+		PX4_ERR("driver not running");
+		return 1;
+	}
+
+	return PX4_OK;
+}
+
+int
+usage()
+{
+	PRINT_MODULE_DESCRIPTION(
+		R"DESCR_STR(
+### Description
+
+Serial bus driver for the Benewake pacecat_lds50c LiDAR.
+
+Most boards are configured to enable/start the driver on a specified UART using the SENS_pacecat_lds50c_CFG parameter.
+
+Setup/usage information: https://docs.px4.io/master/en/sensor/pacecat_lds50c.html
+
+### Examples
+
+Attempt to start driver on a specified serial device.
+$ pacecat_lds50c start -d /dev/ttyS1
+Stop driver
+$ pacecat_lds50c stop
+)DESCR_STR");
+
+	PRINT_MODULE_USAGE_NAME("pacecat_lds50c", "driver");
+	PRINT_MODULE_USAGE_SUBCATEGORY("distance_sensor");
+	PRINT_MODULE_USAGE_COMMAND_DESCR("start","Start driver");
+	PRINT_MODULE_USAGE_PARAM_STRING('d', nullptr, nullptr, "Serial device", false);
+	PRINT_MODULE_USAGE_PARAM_INT('R', 25, 0, 25, "Sensor rotation - downward facing by default", true);
+	PRINT_MODULE_USAGE_COMMAND_DESCR("status","Driver status");
+	PRINT_MODULE_USAGE_COMMAND_DESCR("stop","Stop driver");
+	PRINT_MODULE_USAGE_COMMAND_DESCR("test","Test driver (basic functional tests)");
+	PRINT_MODULE_USAGE_COMMAND_DESCR("status","Print driver status");
+	return PX4_OK;
+}
+
+} // namespace
+
+extern "C" __EXPORT int pacecat_lds50c_main(int argc, char *argv[])
+{
+	int ch = 0;
+	uint8_t rotation = distance_sensor_s::ROTATION_FORWARD_FACING;
+	const char *device_path = PACECAT_LDS50C_DEFAULT_PORT;
+	int myoptind = 1;
+	const char *myoptarg = nullptr;
+
+	while ((ch = px4_getopt(argc, argv, "R:d:", &myoptind, &myoptarg)) != EOF) {
+		switch (ch) {
+		case 'R':
+			rotation = (uint8_t)atoi(myoptarg);
+			break;
+
+		case 'd':
+			device_path = myoptarg;
+			break;
+
+		default:
+			PX4_WARN("Unknown option!");
+			return PX4_ERROR;
+		}
+	}
+
+	if (myoptind >= argc) {
+		PX4_ERR("unrecognized command");
+		return pacecat_lds50c::usage();
+	}
+
+	if (!strcmp(argv[myoptind], "start")) {
+		if (strcmp(device_path, "") != 0) {
+			return pacecat_lds50c::start(device_path, rotation);
+
+		} else {
+			PX4_WARN("Please specify device path!");
+			return pacecat_lds50c::usage();
+		}
+
+	} else if (!strcmp(argv[myoptind], "stop")) {
+		return pacecat_lds50c::stop();
+
+	} else if (!strcmp(argv[myoptind], "status")) {
+		return pacecat_lds50c::status();
+	}
+
+	return pacecat_lds50c::usage();
+}

src/drivers/distance_sensor/pacecat_lds50c/pacecat_lds50c_parser.cpp

@@ -0,0 +1,180 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2017-2019 PX4 Development Team. All rights reserved.
+ *
+ * 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 modified from sf0x_parser.cpp
+ * @author Lorenz Meier <lm@inf.ethz.ch>
+ * @author Chuong Nguyen <chnguye7@asu.edu>
+ * @author Ayush Gaud <ayush.gaud@gmail.com>
+ *
+ * Declarations of parser for the Benewake TFmini laser rangefinder series
+ */
+
+#include "pacecat_lds50c_parser.h"
+#include <string.h>
+#include <stdlib.h>
+
+
+#ifdef PACECAT_LDS50C_DEBUG
+#include <stdio.h>
+
+const char *parser_state[] = {
+	"STATE10_UNSYNC" ,
+	"STATE11_SYNC_1",
+	"STATE11_SYNC_2",
+	"STATE12_GOT_NUM_OF_POINTS",
+	"STATE13_GOT_CHECKSUM",
+
+	"STATE20_UNSYNC",
+	"STATE21_SYNC_1",
+	"STATE21_SYNC_2",
+	"STATE22_GOT_ABCD",
+	"STATE23_GOT_END",
+};
+#endif
+
+int pacecat_lds50c_parse(char c, char *parserbuf, unsigned *parserbuf_index, PACECAT_LDS50C_PARSE_STATE *state, float *dist)
+{
+	int ret = -1;
+	//char *end;
+
+	switch (*state) {
+	case PACECAT_LDS50C_PARSE_STATE::STATE13_GOT_CHECKSUM:
+		if (c == 'Y') {
+			*state = PACECAT_LDS50C_PARSE_STATE::STATE1_SYNC_1;
+			parserbuf[*parserbuf_index] = c;
+			(*parserbuf_index)++;
+
+		} else {
+			*state = PACECAT_LDS50C_PARSE_STATE::STATE0_UNSYNC;
+		}
+
+		break;
+
+	case PACECAT_LDS50C_PARSE_STATE::STATE0_UNSYNC:
+		if (c == 'Y') {
+			*state = PACECAT_LDS50C_PARSE_STATE::STATE1_SYNC_1;
+			parserbuf[*parserbuf_index] = c;
+			(*parserbuf_index)++;
+		}
+
+		break;
+
+	case PACECAT_LDS50C_PARSE_STATE::STATE1_SYNC_1:
+		if (c == 'Y') {
+			*state = PACECAT_LDS50C_PARSE_STATE::STATE1_SYNC_2;
+			parserbuf[*parserbuf_index] = c;
+			(*parserbuf_index)++;
+
+		} else {
+			*state = PACECAT_LDS50C_PARSE_STATE::STATE0_UNSYNC;
+			*parserbuf_index = 0;
+		}
+
+		break;
+
+	case PACECAT_LDS50C_PARSE_STATE::STATE1_SYNC_2:
+		*state = PACECAT_LDS50C_PARSE_STATE::STATE2_GOT_DIST_L;
+		parserbuf[*parserbuf_index] = c;
+		(*parserbuf_index)++;
+
+		break;
+
+	case PACECAT_LDS50C_PARSE_STATE::STATE2_GOT_DIST_L:
+		*state = PACECAT_LDS50C_PARSE_STATE::STATE2_GOT_DIST_H;
+		parserbuf[*parserbuf_index] = c;
+		(*parserbuf_index)++;
+
+		break;
+
+	case PACECAT_LDS50C_PARSE_STATE::STATE2_GOT_DIST_H:
+		*state = PACECAT_LDS50C_PARSE_STATE::STATE3_GOT_STRENGTH_L;
+		parserbuf[*parserbuf_index] = c;
+		(*parserbuf_index)++;
+
+		break;
+
+	case PACECAT_LDS50C_PARSE_STATE::STATE3_GOT_STRENGTH_L:
+		*state = PACECAT_LDS50C_PARSE_STATE::STATE3_GOT_STRENGTH_H;
+		parserbuf[*parserbuf_index] = c;
+		(*parserbuf_index)++;
+
+		break;
+
+	case PACECAT_LDS50C_PARSE_STATE::STATE3_GOT_STRENGTH_H:
+		*state = PACECAT_LDS50C_PARSE_STATE::STATE4_GOT_RESERVED;
+		parserbuf[*parserbuf_index] = c;
+		(*parserbuf_index)++;
+
+		break;
+
+	case PACECAT_LDS50C_PARSE_STATE::STATE4_GOT_RESERVED:
+		*state = PACECAT_LDS50C_PARSE_STATE::STATE5_GOT_QUALITY;
+		parserbuf[*parserbuf_index] = c;
+		(*parserbuf_index)++;
+
+		break;
+
+	case PACECAT_LDS50C_PARSE_STATE::STATE5_GOT_QUALITY:
+		// Find the checksum
+		unsigned char cksm = 0;
+
+		for (int i = 0; i < 8; i++) {
+			cksm += parserbuf[i];
+		}
+
+		if (c == cksm) {
+			parserbuf[*parserbuf_index] = '\0';
+			unsigned int t1 = parserbuf[2];
+			unsigned int t2 = parserbuf[3];
+			t2 <<= 8;
+			t2 += t1;
+			*dist = ((float)t2) / 100;
+			*state = PACECAT_LDS50C_PARSE_STATE::STATE6_GOT_CHECKSUM;
+			*parserbuf_index = 0;
+			ret = 0;
+
+		} else {
+			*state = PACECAT_LDS50C_PARSE_STATE::STATE0_UNSYNC;
+			*parserbuf_index = 0;
+		}
+
+		break;
+	}
+
+#ifdef TFMINI_DEBUG
+	printf("state: PACECAT_LDS50C_PARSE_STATE%s\n", parser_state[*state]);
+#endif
+
+	return ret;
+}

src/drivers/distance_sensor/pacecat_lds50c/pacecat_lds50c_parser.h

@@ -0,0 +1,74 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2017-2019 PX4 Development Team. All rights reserved.
+ *
+ * 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 modified from sf0x_parser.cpp
+ * @author Lorenz Meier <lm@inf.ethz.ch>
+ * @author Chuong Nguyen <chnguye7@asu.edu>
+ * @author Ayush Gaud <ayush.gaud@gmail.com>
+ *
+ * Declarations of parser for the Benewake TFmini laser rangefinder series
+ */
+
+#pragma once
+
+// Data Format for Benewake TFmini
+// ===============================
+// 9 bytes total per message:
+// 1) 0x59
+// 2) 0x59
+// 3) Dist_L (low 8bit)
+// 4) Dist_H (high 8bit)
+// 5) Strength_L (low 8bit)
+// 6) Strength_H (high 8bit)
+// 7) Reserved bytes
+// 8) Original signal quality degree
+// 9) Checksum parity bit (low 8bit), Checksum = Byte1 + Byte2 +...+Byte8. This is only a low 8bit though
+
+
+enum class PACECAT_LDS50C_PARSE_STATE {
+	STATE10_UNSYNC = 0,
+	STATE11_SYNC_1,
+	STATE11_SYNC_2,
+	STATE12_GOT_NUM_OF_POINTS,
+	STATE13_GOT_CHECKSUM,
+
+	STATE20_UNSYNC,
+	STATE21_SYNC_1,
+	STATE21_SYNC_2,
+	STATE22_GOT_ABCD,
+	STATE23_GOT_END,
+
+};
+
+int pacecat_lds50c_parse(char c, char *parserbuf, unsigned *parserbuf_index, TFMINI_PARSE_STATE *state, float *dist);

src/drivers/drv_sensor.h

@@ -199,6 +199,7 @@
 #define DRV_DIST_DEVTYPE_MR72        0xB2
 #define DRV_DIST_DEVTYPE_ENZHAO        0xB4
 
+#define DRV_DIST_DEVTYPE_PACECAT_LDS50C  0xC0
 
 #define DRV_DEVTYPE_UNUSED		0xff