px4fmu move RC input to new rc_input driver

src/drivers/rc_input/CMakeLists.txt

@@ -0,0 +1,43 @@
+############################################################################
+#
+#   Copyright (c) 2015 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__rc_input
+	MAIN rc_input
+	STACK_MAIN 1200
+	COMPILE_FLAGS
+	SRCS
+		RCInput.cpp
+		crsf_telemetry.cpp
+	DEPENDS
+		rc
+	)

src/drivers/rc_input/RCInput.cpp

@@ -0,0 +1,799 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2012-2018 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 "RCInput.hpp"
+
+#include "crsf_telemetry.h"
+
+using namespace time_literals;
+
+#define SCHEDULE_INTERVAL	4000	/**< The schedule interval in usec (250 Hz) */
+
+#if defined(SPEKTRUM_POWER)
+static bool bind_spektrum(int arg);
+#endif /* SPEKTRUM_POWER */
+
+work_s RCInput::_work = {};
+
+RCInput::RCInput(bool run_as_task)
+{
+	// rc input, published to ORB
+	_rc_in.input_source = input_rc_s::RC_INPUT_SOURCE_PX4FMU_PPM;
+
+	// initialize it as RC lost
+	_rc_in.rc_lost = true;
+
+	// initialize raw_rc values and count
+	for (unsigned i = 0; i < input_rc_s::RC_INPUT_MAX_CHANNELS; i++) {
+		_raw_rc_values[i] = UINT16_MAX;
+	}
+}
+
+RCInput::~RCInput()
+{
+	orb_unadvertise(_to_input_rc);
+
+	orb_unsubscribe(_adc_sub);
+	orb_unsubscribe(_vehicle_cmd_sub);
+
+#ifdef RC_SERIAL_PORT
+	dsm_deinit();
+#endif
+
+	if (_crsf_telemetry) {
+		delete (_crsf_telemetry);
+	}
+}
+
+int
+RCInput::init()
+{
+	_adc_sub = orb_subscribe(ORB_ID(adc_report));
+
+#ifdef RC_SERIAL_PORT
+
+#  ifdef RF_RADIO_POWER_CONTROL
+	// power radio on
+	RF_RADIO_POWER_CONTROL(true);
+#  endif
+	_vehicle_cmd_sub = orb_subscribe(ORB_ID(vehicle_command));
+	// dsm_init sets some file static variables and returns a file descriptor
+	_rcs_fd = dsm_init(RC_SERIAL_PORT);
+	// assume SBUS input and immediately switch it to
+	// so that if Single wire mode on TX there will be only
+	// a short contention
+	sbus_config(_rcs_fd, board_supports_single_wire(RC_UXART_BASE));
+#  ifdef GPIO_PPM_IN
+	// disable CPPM input by mapping it away from the timer capture input
+	px4_arch_unconfiggpio(GPIO_PPM_IN);
+#  endif
+#endif
+
+	return 0;
+}
+
+int
+RCInput::task_spawn(int argc, char *argv[])
+{
+	bool run_as_task = false;
+	bool error_flag = false;
+
+	int myoptind = 1;
+	int ch;
+	const char *myoptarg = nullptr;
+
+	while ((ch = px4_getopt(argc, argv, "t", &myoptind, &myoptarg)) != EOF) {
+		switch (ch) {
+		case 't':
+			run_as_task = true;
+			break;
+
+		case '?':
+			error_flag = true;
+			break;
+
+		default:
+			PX4_WARN("unrecognized flag");
+			error_flag = true;
+			break;
+		}
+	}
+
+	if (error_flag) {
+		return -1;
+	}
+
+
+	if (!run_as_task) {
+
+		/* schedule a cycle to start things */
+		int ret = work_queue(HPWORK, &_work, (worker_t)&RCInput::cycle_trampoline, nullptr, 0);
+
+		if (ret < 0) {
+			return ret;
+		}
+
+		_task_id = task_id_is_work_queue;
+
+	} else {
+
+		/* start the IO interface task */
+
+		_task_id = px4_task_spawn_cmd("rc_input",
+					      SCHED_DEFAULT,
+					      SCHED_PRIORITY_SLOW_DRIVER,
+					      1000,
+					      (px4_main_t)&run_trampoline,
+					      nullptr);
+
+		if (_task_id < 0) {
+			_task_id = -1;
+			return -errno;
+		}
+	}
+
+	return PX4_OK;
+}
+
+void
+RCInput::cycle_trampoline(void *arg)
+{
+	RCInput *dev = reinterpret_cast<RCInput *>(arg);
+
+	// check if the trampoline is called for the first time
+	if (!dev) {
+		dev = new RCInput(false);
+
+		if (!dev) {
+			PX4_ERR("alloc failed");
+			return;
+		}
+
+		if (dev->init() != 0) {
+			PX4_ERR("init failed");
+			delete dev;
+			return;
+		}
+
+		_object = dev;
+	}
+
+	dev->cycle();
+}
+
+void
+RCInput::fill_rc_in(uint16_t raw_rc_count_local,
+		    uint16_t raw_rc_values_local[input_rc_s::RC_INPUT_MAX_CHANNELS],
+		    hrt_abstime now, bool frame_drop, bool failsafe,
+		    unsigned frame_drops, int rssi = -1)
+{
+	// fill rc_in struct for publishing
+	_rc_in.channel_count = raw_rc_count_local;
+
+	if (_rc_in.channel_count > input_rc_s::RC_INPUT_MAX_CHANNELS) {
+		_rc_in.channel_count = input_rc_s::RC_INPUT_MAX_CHANNELS;
+	}
+
+	unsigned valid_chans = 0;
+
+	for (unsigned i = 0; i < _rc_in.channel_count; i++) {
+		_rc_in.values[i] = raw_rc_values_local[i];
+
+		if (raw_rc_values_local[i] != UINT16_MAX) {
+			valid_chans++;
+		}
+
+		// once filled, reset values back to default
+		_raw_rc_values[i] = UINT16_MAX;
+	}
+
+	_rc_in.timestamp = now;
+	_rc_in.timestamp_last_signal = _rc_in.timestamp;
+	_rc_in.rc_ppm_frame_length = 0;
+
+	/* fake rssi if no value was provided */
+	if (rssi == -1) {
+
+		/* set RSSI if analog RSSI input is present */
+		if (_analog_rc_rssi_stable) {
+			float rssi_analog = ((_analog_rc_rssi_volt - 0.2f) / 3.0f) * 100.0f;
+
+			if (rssi_analog > 100.0f) {
+				rssi_analog = 100.0f;
+			}
+
+			if (rssi_analog < 0.0f) {
+				rssi_analog = 0.0f;
+			}
+
+			_rc_in.rssi = rssi_analog;
+
+		} else {
+			_rc_in.rssi = 255;
+		}
+
+	} else {
+		_rc_in.rssi = rssi;
+	}
+
+	if (valid_chans == 0) {
+		_rc_in.rssi = 0;
+	}
+
+	_rc_in.rc_failsafe = failsafe;
+	_rc_in.rc_lost = (valid_chans == 0);
+	_rc_in.rc_lost_frame_count = frame_drops;
+	_rc_in.rc_total_frame_count = 0;
+}
+
+#ifdef RC_SERIAL_PORT
+void RCInput::set_rc_scan_state(RC_SCAN newState)
+{
+//    PX4_WARN("RCscan: %s failed, trying %s", RCInput::RC_SCAN_STRING[_rc_scan_state], RCInput::RC_SCAN_STRING[newState]);
+	_rc_scan_begin = 0;
+	_rc_scan_state = newState;
+}
+
+void RCInput::rc_io_invert(bool invert, uint32_t uxart_base)
+{
+	INVERT_RC_INPUT(invert, uxart_base);
+}
+#endif
+
+void
+RCInput::run()
+{
+	if (init() != 0) {
+		PX4_ERR("init failed");
+		exit_and_cleanup();
+		return;
+	}
+
+	cycle();
+}
+
+void
+RCInput::cycle()
+{
+	while (true) {
+
+		_cycle_timestamp = hrt_absolute_time();
+
+#if defined(SPEKTRUM_POWER)
+		/* vehicle command */
+		bool vehicle_command_updated = false;
+		orb_check(_vehicle_cmd_sub, &vehicle_command_updated);
+
+		if (vehicle_command_updated) {
+			vehicle_command_s vcmd = {};
+			orb_copy(ORB_ID(vehicle_command), _vehicle_cmd_sub, &vcmd);
+
+			// Check for a pairing command
+			if ((unsigned int)vcmd.command == vehicle_command_s::VEHICLE_CMD_START_RX_PAIR) {
+				if (!_rc_scan_locked /* !_armed.armed */) { // TODO: add armed check?
+					if ((int)vcmd.param1 == 0) {
+						// DSM binding command
+						int dsm_bind_mode = (int)vcmd.param2;
+
+						int dsm_bind_pulses = 0;
+
+						if (dsm_bind_mode == 0) {
+							dsm_bind_pulses = DSM2_BIND_PULSES;
+
+						} else if (dsm_bind_mode == 1) {
+							dsm_bind_pulses = DSMX_BIND_PULSES;
+
+						} else {
+							dsm_bind_pulses = DSMX8_BIND_PULSES;
+						}
+
+						bind_spektrum(dsm_bind_pulses);
+					}
+
+				} else {
+					PX4_WARN("system armed, bind request rejected");
+				}
+			}
+		}
+
+#endif /* SPEKTRUM_POWER */
+
+		/* update ADC sampling */
+#ifdef ADC_RC_RSSI_CHANNEL
+		bool adc_updated = false;
+		orb_check(_adc_sub, &adc_updated);
+
+		if (adc_updated) {
+
+			struct adc_report_s adc;
+			orb_copy(ORB_ID(adc_report), _adc_sub, &adc);
+			const unsigned adc_chans = sizeof(adc.channel_id) / sizeof(adc.channel_id[0]);
+
+			for (unsigned i = 0; i < adc_chans; i++) {
+				if (adc.channel_id[i] == ADC_RC_RSSI_CHANNEL) {
+
+					if (_analog_rc_rssi_volt < 0.0f) {
+						_analog_rc_rssi_volt = adc.channel_value[i];
+					}
+
+					_analog_rc_rssi_volt = _analog_rc_rssi_volt * 0.995f + adc.channel_value[i] * 0.005f;
+
+					/* only allow this to be used if we see a high RSSI once */
+					if (_analog_rc_rssi_volt > 2.5f) {
+						_analog_rc_rssi_stable = true;
+					}
+				}
+			}
+		}
+
+#endif /* ADC_RC_RSSI_CHANNEL */
+
+		bool rc_updated = false;
+
+#ifdef RC_SERIAL_PORT
+		// This block scans for a supported serial RC input and locks onto the first one found
+		// Scan for 300 msec, then switch protocol
+		constexpr hrt_abstime rc_scan_max = 300_ms;
+
+		bool sbus_failsafe, sbus_frame_drop;
+		unsigned frame_drops;
+		bool dsm_11_bit;
+
+		if (_report_lock && _rc_scan_locked) {
+			_report_lock = false;
+			//PX4_WARN("RCscan: %s RC input locked", RC_SCAN_STRING[_rc_scan_state]);
+		}
+
+		int newBytes = 0;
+
+		if (_run_as_task) {
+			// TODO: needs work (poll _rcs_fd)
+			// int ret = poll(fds, sizeof(fds) / sizeof(fds[0]), 100);
+			// then update priority to SCHED_PRIORITY_FAST_DRIVER
+			// read all available data from the serial RC input UART
+			newBytes = ::read(_rcs_fd, &_rcs_buf[0], SBUS_BUFFER_SIZE);
+
+		} else {
+			// read all available data from the serial RC input UART
+			newBytes = ::read(_rcs_fd, &_rcs_buf[0], SBUS_BUFFER_SIZE);
+		}
+
+		switch (_rc_scan_state) {
+		case RC_SCAN_SBUS:
+			if (_rc_scan_begin == 0) {
+				_rc_scan_begin = _cycle_timestamp;
+				// Configure serial port for SBUS
+				sbus_config(_rcs_fd, board_supports_single_wire(RC_UXART_BASE));
+				rc_io_invert(true, RC_UXART_BASE);
+
+			} else if (_rc_scan_locked
+				   || _cycle_timestamp - _rc_scan_begin < rc_scan_max) {
+
+				// parse new data
+				if (newBytes > 0) {
+					rc_updated = sbus_parse(_cycle_timestamp, &_rcs_buf[0], newBytes, &_raw_rc_values[0], &_raw_rc_count, &sbus_failsafe,
+								&sbus_frame_drop, &frame_drops, input_rc_s::RC_INPUT_MAX_CHANNELS);
+
+					if (rc_updated) {
+						// we have a new SBUS frame. Publish it.
+						_rc_in.input_source = input_rc_s::RC_INPUT_SOURCE_PX4FMU_SBUS;
+						fill_rc_in(_raw_rc_count, _raw_rc_values, _cycle_timestamp,
+							   sbus_frame_drop, sbus_failsafe, frame_drops);
+						_rc_scan_locked = true;
+					}
+				}
+
+			} else {
+				// Scan the next protocol
+				set_rc_scan_state(RC_SCAN_DSM);
+			}
+
+			break;
+
+		case RC_SCAN_DSM:
+			if (_rc_scan_begin == 0) {
+				_rc_scan_begin = _cycle_timestamp;
+				//			// Configure serial port for DSM
+				dsm_config(_rcs_fd);
+				rc_io_invert(false, RC_UXART_BASE);
+
+			} else if (_rc_scan_locked
+				   || _cycle_timestamp - _rc_scan_begin < rc_scan_max) {
+
+				if (newBytes > 0) {
+					int8_t dsm_rssi;
+
+					// parse new data
+					rc_updated = dsm_parse(_cycle_timestamp, &_rcs_buf[0], newBytes, &_raw_rc_values[0], &_raw_rc_count,
+							       &dsm_11_bit, &frame_drops, &dsm_rssi, input_rc_s::RC_INPUT_MAX_CHANNELS);
+
+					if (rc_updated) {
+						// we have a new DSM frame. Publish it.
+						_rc_in.input_source = input_rc_s::RC_INPUT_SOURCE_PX4FMU_DSM;
+						fill_rc_in(_raw_rc_count, _raw_rc_values, _cycle_timestamp,
+							   false, false, frame_drops, dsm_rssi);
+						_rc_scan_locked = true;
+					}
+				}
+
+			} else {
+				// Scan the next protocol
+				set_rc_scan_state(RC_SCAN_ST24);
+			}
+
+			break;
+
+		case RC_SCAN_ST24:
+			if (_rc_scan_begin == 0) {
+				_rc_scan_begin = _cycle_timestamp;
+				// Configure serial port for DSM
+				dsm_config(_rcs_fd);
+				rc_io_invert(false, RC_UXART_BASE);
+
+			} else if (_rc_scan_locked
+				   || _cycle_timestamp - _rc_scan_begin < rc_scan_max) {
+
+				if (newBytes > 0) {
+					// parse new data
+					uint8_t st24_rssi, lost_count;
+
+					rc_updated = false;
+
+					for (unsigned i = 0; i < (unsigned)newBytes; i++) {
+						/* set updated flag if one complete packet was parsed */
+						st24_rssi = RC_INPUT_RSSI_MAX;
+						rc_updated = (OK == st24_decode(_rcs_buf[i], &st24_rssi, &lost_count,
+										&_raw_rc_count, _raw_rc_values, input_rc_s::RC_INPUT_MAX_CHANNELS));
+					}
+
+					// The st24 will keep outputting RC channels and RSSI even if RC has been lost.
+					// The only way to detect RC loss is therefore to look at the lost_count.
+
+					if (rc_updated) {
+						if (lost_count == 0) {
+							// we have a new ST24 frame. Publish it.
+							_rc_in.input_source = input_rc_s::RC_INPUT_SOURCE_PX4FMU_ST24;
+							fill_rc_in(_raw_rc_count, _raw_rc_values, _cycle_timestamp,
+								   false, false, frame_drops, st24_rssi);
+							_rc_scan_locked = true;
+
+						} else {
+							// if the lost count > 0 means that there is an RC loss
+							_rc_in.rc_lost = true;
+						}
+					}
+				}
+
+			} else {
+				// Scan the next protocol
+				set_rc_scan_state(RC_SCAN_SUMD);
+			}
+
+			break;
+
+		case RC_SCAN_SUMD:
+			if (_rc_scan_begin == 0) {
+				_rc_scan_begin = _cycle_timestamp;
+				// Configure serial port for DSM
+				dsm_config(_rcs_fd);
+				rc_io_invert(false, RC_UXART_BASE);
+
+			} else if (_rc_scan_locked
+				   || _cycle_timestamp - _rc_scan_begin < rc_scan_max) {
+
+				if (newBytes > 0) {
+					// parse new data
+					uint8_t sumd_rssi, rx_count;
+					bool sumd_failsafe;
+
+					rc_updated = false;
+
+					for (unsigned i = 0; i < (unsigned)newBytes; i++) {
+						/* set updated flag if one complete packet was parsed */
+						sumd_rssi = RC_INPUT_RSSI_MAX;
+						rc_updated = (OK == sumd_decode(_rcs_buf[i], &sumd_rssi, &rx_count,
+										&_raw_rc_count, _raw_rc_values, input_rc_s::RC_INPUT_MAX_CHANNELS, &sumd_failsafe));
+					}
+
+					if (rc_updated) {
+						// we have a new SUMD frame. Publish it.
+						_rc_in.input_source = input_rc_s::RC_INPUT_SOURCE_PX4FMU_SUMD;
+						fill_rc_in(_raw_rc_count, _raw_rc_values, _cycle_timestamp,
+							   false, sumd_failsafe, frame_drops, sumd_rssi);
+						_rc_scan_locked = true;
+					}
+				}
+
+			} else {
+				// Scan the next protocol
+				set_rc_scan_state(RC_SCAN_PPM);
+			}
+
+			break;
+
+		case RC_SCAN_PPM:
+			// skip PPM if it's not supported
+#ifdef HRT_PPM_CHANNEL
+			if (_rc_scan_begin == 0) {
+				_rc_scan_begin = _cycle_timestamp;
+				// Configure timer input pin for CPPM
+				px4_arch_configgpio(GPIO_PPM_IN);
+				rc_io_invert(false, RC_UXART_BASE);
+
+			} else if (_rc_scan_locked || _cycle_timestamp - _rc_scan_begin < rc_scan_max) {
+
+				// see if we have new PPM input data
+				if ((ppm_last_valid_decode != _rc_in.timestamp_last_signal) && ppm_decoded_channels > 3) {
+					// we have a new PPM frame. Publish it.
+					rc_updated = true;
+					_rc_in.input_source = input_rc_s::RC_INPUT_SOURCE_PX4FMU_PPM;
+					fill_rc_in(ppm_decoded_channels, ppm_buffer, _cycle_timestamp, false, false, 0);
+					_rc_scan_locked = true;
+					_rc_in.rc_ppm_frame_length = ppm_frame_length;
+					_rc_in.timestamp_last_signal = ppm_last_valid_decode;
+				}
+
+			} else {
+				// disable CPPM input by mapping it away from the timer capture input
+				px4_arch_unconfiggpio(GPIO_PPM_IN);
+				// Scan the next protocol
+				set_rc_scan_state(RC_SCAN_CRSF);
+			}
+
+#else   // skip PPM if it's not supported
+			set_rc_scan_state(RC_SCAN_CRSF);
+
+#endif  // HRT_PPM_CHANNEL
+
+			break;
+
+		case RC_SCAN_CRSF:
+			if (_rc_scan_begin == 0) {
+				_rc_scan_begin = _cycle_timestamp;
+				// Configure serial port for CRSF
+				crsf_config(_rcs_fd);
+				rc_io_invert(false, RC_UXART_BASE);
+
+			} else if (_rc_scan_locked
+				   || _cycle_timestamp - _rc_scan_begin < rc_scan_max) {
+
+				// parse new data
+				if (newBytes > 0) {
+					rc_updated = crsf_parse(_cycle_timestamp, &_rcs_buf[0], newBytes, &_raw_rc_values[0], &_raw_rc_count,
+								input_rc_s::RC_INPUT_MAX_CHANNELS);
+
+					if (rc_updated) {
+						// we have a new CRSF frame. Publish it.
+						_rc_in.input_source = input_rc_s::RC_INPUT_SOURCE_PX4FMU_CRSF;
+						fill_rc_in(_raw_rc_count, _raw_rc_values, _cycle_timestamp, false, false, 0);
+
+						// Enable CRSF Telemetry only on the Omnibus, because on Pixhawk (-related) boards
+						// we cannot write to the RC UART
+						// It might work on FMU-v5. Or another option is to use a different UART port
+#ifdef CONFIG_ARCH_BOARD_OMNIBUS_F4SD
+
+						if (!_rc_scan_locked && !_crsf_telemetry) {
+							_crsf_telemetry = new CRSFTelemetry(_rcs_fd);
+						}
+
+#endif /* CONFIG_ARCH_BOARD_OMNIBUS_F4SD */
+
+						_rc_scan_locked = true;
+
+						if (_crsf_telemetry) {
+							_crsf_telemetry->update(_cycle_timestamp);
+						}
+					}
+				}
+
+			} else {
+				// Scan the next protocol
+				set_rc_scan_state(RC_SCAN_SBUS);
+			}
+
+			break;
+		}
+
+#else  // RC_SERIAL_PORT not defined
+#ifdef HRT_PPM_CHANNEL
+
+		// see if we have new PPM input data
+		if ((ppm_last_valid_decode != _rc_in.timestamp_last_signal) && ppm_decoded_channels > 3) {
+			// we have a new PPM frame. Publish it.
+			rc_updated = true;
+			fill_rc_in(ppm_decoded_channels, ppm_buffer, _cycle_timestamp, false, false, 0);
+			_rc_in.rc_ppm_frame_length = ppm_frame_length;
+			_rc_in.timestamp_last_signal = ppm_last_valid_decode;
+		}
+
+#endif  // HRT_PPM_CHANNEL
+#endif  // RC_SERIAL_PORT
+
+		if (rc_updated) {
+			int instance;
+			orb_publish_auto(ORB_ID(input_rc), &_to_input_rc, &_rc_in, &instance, ORB_PRIO_DEFAULT);
+
+		} else if (!rc_updated && ((hrt_absolute_time() - _rc_in.timestamp_last_signal) > 1_s)) {
+			_rc_scan_locked = false;
+		}
+
+		if (_run_as_task) {
+			if (should_exit()) {
+				break;
+			}
+
+		} else {
+			if (should_exit()) {
+				exit_and_cleanup();
+
+			} else {
+				/* schedule next cycle */
+				work_queue(HPWORK, &_work, (worker_t)&RCInput::cycle_trampoline, this, USEC2TICK(SCHEDULE_INTERVAL));
+			}
+
+			break;
+		}
+	}
+}
+
+#if defined(SPEKTRUM_POWER)
+bool bind_spektrum(int arg)
+{
+	int ret = PX4_ERROR;
+
+	/* specify 11ms DSMX. RX will automatically fall back to 22ms or DSM2 if necessary */
+
+	/* only allow DSM2, DSM-X and DSM-X with more than 7 channels */
+	PX4_INFO("DSM_BIND_START: DSM%s RX", (arg == 0) ? "2" : ((arg == 1) ? "-X" : "-X8"));
+
+	if (arg == DSM2_BIND_PULSES ||
+	    arg == DSMX_BIND_PULSES ||
+	    arg == DSMX8_BIND_PULSES) {
+
+		dsm_bind(DSM_CMD_BIND_POWER_DOWN, 0);
+
+		dsm_bind(DSM_CMD_BIND_SET_RX_OUT, 0);
+		usleep(500000);
+
+		dsm_bind(DSM_CMD_BIND_POWER_UP, 0);
+		usleep(72000);
+
+		irqstate_t flags = px4_enter_critical_section();
+		dsm_bind(DSM_CMD_BIND_SEND_PULSES, arg);
+		px4_leave_critical_section(flags);
+
+		usleep(50000);
+
+		dsm_bind(DSM_CMD_BIND_REINIT_UART, 0);
+
+		ret = OK;
+
+	} else {
+		PX4_ERR("DSM bind failed");
+		ret = -EINVAL;
+	}
+
+	return (ret == PX4_OK);
+}
+#endif /* SPEKTRUM_POWER */
+
+RCInput *RCInput::instantiate(int argc, char *argv[])
+{
+	// No arguments to parse. We also know that we should run as task
+	return new RCInput(true);
+}
+
+int RCInput::custom_command(int argc, char *argv[])
+{
+#if defined(SPEKTRUM_POWER)
+	const char *verb = argv[0];
+
+	if (!strcmp(verb, "bind")) {
+		bind_spektrum(DSMX8_BIND_PULSES);
+		return 0;
+	}
+
+#endif /* SPEKTRUM_POWER */
+
+	/* start the FMU if not running */
+	if (!is_running()) {
+		int ret = RCInput::task_spawn(argc, argv);
+
+		if (ret) {
+			return ret;
+		}
+	}
+
+	return print_usage("unknown command");
+}
+
+int RCInput::print_usage(const char *reason)
+{
+	if (reason) {
+		PX4_WARN("%s\n", reason);
+	}
+
+	PRINT_MODULE_DESCRIPTION(
+		R"DESCR_STR(
+### Description
+This module does the RC input parsing and auto-selecting the method. Supported methods are:
+- PPM
+- SBUS
+- DSM
+- SUMD
+- ST24
+- TBS Crossfire (CRSF)
+
+### Implementation
+By default the module runs on the work queue, to reduce RAM usage. It can also be run in its own thread,
+specified via start flag -t, to reduce latency.
+When running on the work queue, it schedules at a fixed frequency.
+)DESCR_STR");
+
+	PRINT_MODULE_USAGE_NAME("rc_input", "driver");
+	PRINT_MODULE_USAGE_COMMAND_DESCR("start", "Start the task (without any mode set, use any of the mode_* cmds)");
+	PRINT_MODULE_USAGE_PARAM_FLAG('t', "Run as separate task instead of the work queue", true);
+
+#if defined(SPEKTRUM_POWER)
+	PRINT_MODULE_USAGE_COMMAND_DESCR("bind", "Send a DSM bind command (module must be running)");
+#endif /* SPEKTRUM_POWER */
+
+	PRINT_MODULE_USAGE_DEFAULT_COMMANDS();
+
+	return 0;
+}
+
+int RCInput::print_status()
+{
+	PX4_INFO("Running %s", (_run_as_task ? "as task" : "on work queue"));
+
+	if (!_run_as_task) {
+		PX4_INFO("Max update rate: %i Hz", _current_update_rate);
+	}
+
+	PX4_INFO("RC scan state: %s, locked: %s", RC_SCAN_STRING[_rc_scan_state], _rc_scan_locked ? "yes" : "no");
+	PX4_INFO("CRSF Telemetry: %s", _crsf_telemetry ? "yes" : "no");
+#ifdef RC_SERIAL_PORT
+	PX4_INFO("SBUS frame drops: %u", sbus_dropped_frames());
+#endif
+
+	return 0;
+}
+
+extern "C" __EXPORT int rc_input_main(int argc, char *argv[]);
+
+int
+rc_input_main(int argc, char *argv[])
+{
+	return RCInput::main(argc, argv);
+}

src/drivers/rc_input/RCInput.hpp

@@ -0,0 +1,155 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2012-2018 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.
+ *
+ ****************************************************************************/
+
+#pragma once
+
+#include <cfloat>
+
+#include <board_config.h>
+#include <drivers/drv_hrt.h>
+#include <drivers/drv_rc_input.h>
+#include <lib/rc/crsf.h>
+#include <lib/rc/dsm.h>
+#include <lib/rc/sbus.h>
+#include <lib/rc/st24.h>
+#include <lib/rc/sumd.h>
+#include <px4_config.h>
+#include <px4_getopt.h>
+#include <px4_log.h>
+#include <px4_module.h>
+#include <px4_workqueue.h>
+#include <uORB/topics/adc_report.h>
+#include <uORB/topics/input_rc.h>
+#include <uORB/topics/vehicle_command.h>
+
+#include "crsf_telemetry.h"
+
+#ifdef HRT_PPM_CHANNEL
+# include <systemlib/ppm_decode.h>
+#endif
+
+class RCInput : public ModuleBase<RCInput>
+{
+public:
+
+	RCInput(bool run_as_task);
+	virtual ~RCInput();
+
+	/** @see ModuleBase */
+	static int task_spawn(int argc, char *argv[]);
+
+	/** @see ModuleBase */
+	static RCInput *instantiate(int argc, char *argv[]);
+
+	/** @see ModuleBase */
+	static int custom_command(int argc, char *argv[]);
+
+	/** @see ModuleBase */
+	static int print_usage(const char *reason = nullptr);
+
+	/** @see ModuleBase::run() */
+	void run() override;
+
+	/**
+	 * run the main loop: if running as task, continuously iterate, otherwise execute only one single cycle
+	 */
+	void cycle();
+
+	/** @see ModuleBase::print_status() */
+	int print_status() override;
+
+	int	init();
+
+private:
+	enum RC_SCAN {
+		RC_SCAN_PPM = 0,
+		RC_SCAN_SBUS,
+		RC_SCAN_DSM,
+		RC_SCAN_SUMD,
+		RC_SCAN_ST24,
+		RC_SCAN_CRSF
+	};
+	enum RC_SCAN _rc_scan_state = RC_SCAN_SBUS;
+
+	char const *RC_SCAN_STRING[6] = {
+		"PPM",
+		"SBUS",
+		"DSM",
+		"SUMD",
+		"ST24",
+		"CRSF"
+	};
+
+	hrt_abstime _rc_scan_begin{0};
+	bool _rc_scan_locked{false};
+	bool _report_lock{true};
+
+	hrt_abstime _cycle_timestamp{0};
+
+	unsigned	_current_update_rate{0};
+	bool 		_run_as_task{false};
+
+	static struct work_s	_work;
+
+	int		_vehicle_cmd_sub{-1};
+	int		_adc_sub{-1};
+
+	rc_input_values	_rc_in{};
+
+	float		_analog_rc_rssi_volt{-1.0f};
+	bool		_analog_rc_rssi_stable{false};
+
+	orb_advert_t	_to_input_rc{nullptr};
+
+	int		_rcs_fd{-1};
+
+	uint8_t _rcs_buf[SBUS_BUFFER_SIZE] {};
+
+	uint16_t _raw_rc_values[input_rc_s::RC_INPUT_MAX_CHANNELS] {};
+	uint16_t _raw_rc_count{};
+
+	CRSFTelemetry *_crsf_telemetry{nullptr};
+
+	static void	cycle_trampoline(void *arg);
+	int 		start();
+
+	void fill_rc_in(uint16_t raw_rc_count_local,
+			uint16_t raw_rc_values_local[input_rc_s::RC_INPUT_MAX_CHANNELS],
+			hrt_abstime now, bool frame_drop, bool failsafe,
+			unsigned frame_drops, int rssi);
+
+	void set_rc_scan_state(RC_SCAN _rc_scan_state);
+
+	void rc_io_invert(bool invert, uint32_t uxart_base);
+
+};

src/drivers/rc_input/crsf_telemetry.cpp

@@ -0,0 +1,206 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2018 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 "crsf_telemetry.h"
+#include <lib/rc/crsf.h>
+
+CRSFTelemetry::CRSFTelemetry(int uart_fd)
+	: _vehicle_gps_position_sub(orb_subscribe(ORB_ID(vehicle_gps_position))),
+	  _battery_status_sub(orb_subscribe(ORB_ID(battery_status))),
+	  _vehicle_attitude_sub(orb_subscribe(ORB_ID(vehicle_attitude))),
+	  _vehicle_status_sub(orb_subscribe(ORB_ID(vehicle_status))),
+	  _uart_fd(uart_fd)
+{
+}
+
+CRSFTelemetry::~CRSFTelemetry()
+{
+	orb_unsubscribe(_vehicle_gps_position_sub);
+	orb_unsubscribe(_battery_status_sub);
+	orb_unsubscribe(_vehicle_attitude_sub);
+	orb_unsubscribe(_vehicle_status_sub);
+}
+
+bool CRSFTelemetry::update(const hrt_abstime &now)
+{
+	const int update_rate_hz = 10;
+
+	if (now - _last_update <= 1_s / (update_rate_hz * num_data_types)) {
+		return false;
+	}
+
+	bool sent = false;
+
+	switch (_next_type) {
+	case 0:
+		sent = send_battery();
+		break;
+
+	case 1:
+		sent = send_gps();
+		break;
+
+	case 2:
+		sent = send_attitude();
+		break;
+
+	case 3:
+		sent = send_flight_mode();
+		break;
+	}
+
+	_last_update = now;
+	_next_type = (_next_type + 1) % num_data_types;
+
+	return sent;
+}
+
+bool CRSFTelemetry::send_battery()
+{
+	battery_status_s battery_status;
+
+	if (orb_copy(ORB_ID(battery_status), _battery_status_sub, &battery_status) != 0) {
+		return false;
+	}
+
+	uint16_t voltage = battery_status.voltage_filtered_v * 10;
+	uint16_t current = battery_status.current_filtered_a * 10;
+	int fuel = battery_status.discharged_mah;
+	uint8_t remaining = battery_status.remaining * 100;
+	return crsf_send_telemetry_battery(_uart_fd, voltage, current, fuel, remaining);
+}
+
+bool CRSFTelemetry::send_gps()
+{
+	vehicle_gps_position_s vehicle_gps_position;
+
+	if (orb_copy(ORB_ID(vehicle_gps_position), _vehicle_gps_position_sub, &vehicle_gps_position) != 0) {
+		return false;
+	}
+
+	int32_t latitude = vehicle_gps_position.lat;
+	int32_t longitude = vehicle_gps_position.lon;
+	uint16_t groundspeed = vehicle_gps_position.vel_d_m_s / 3.6f * 10.f;
+	uint16_t gps_heading = math::degrees(vehicle_gps_position.cog_rad) * 100.f;
+	uint16_t altitude = vehicle_gps_position.alt + 1000;
+	uint8_t num_satellites = vehicle_gps_position.satellites_used;
+
+	return crsf_send_telemetry_gps(_uart_fd, latitude, longitude, groundspeed,
+				       gps_heading, altitude, num_satellites);
+}
+
+bool CRSFTelemetry::send_attitude()
+{
+	vehicle_attitude_s vehicle_attitude;
+
+	if (orb_copy(ORB_ID(vehicle_attitude), _vehicle_attitude_sub, &vehicle_attitude) != 0) {
+		return false;
+	}
+
+	matrix::Eulerf attitude = matrix::Quatf(vehicle_attitude.q);
+	int16_t pitch = attitude(1) * 1e4f;
+	int16_t roll = attitude(0) * 1e4f;
+	int16_t yaw = attitude(2) * 1e4f;
+	return crsf_send_telemetry_attitude(_uart_fd, pitch, roll, yaw);
+}
+
+bool CRSFTelemetry::send_flight_mode()
+{
+	vehicle_status_s vehicle_status;
+
+	if (orb_copy(ORB_ID(vehicle_status), _vehicle_status_sub, &vehicle_status) != 0) {
+		return false;
+	}
+
+	const char *flight_mode = "(unknown)";
+
+	switch (vehicle_status.nav_state) {
+	case vehicle_status_s::NAVIGATION_STATE_MANUAL:
+		flight_mode = "Manual";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_ALTCTL:
+		flight_mode = "Altitude";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_POSCTL:
+		flight_mode = "Position";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_RTL:
+		flight_mode = "Return";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_MISSION:
+		flight_mode = "Mission";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_LOITER:
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_RCRECOVER:
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_RTGS:
+	case vehicle_status_s::NAVIGATION_STATE_DESCEND:
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_TAKEOFF:
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_LAND:
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_FOLLOW_TARGET:
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_PRECLAND:
+		flight_mode = "Auto";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_LANDENGFAIL:
+	case vehicle_status_s::NAVIGATION_STATE_AUTO_LANDGPSFAIL:
+		flight_mode = "Failure";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_ACRO:
+		flight_mode = "Acro";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_TERMINATION:
+		flight_mode = "Terminate";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_OFFBOARD:
+		flight_mode = "Offboard";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_STAB:
+		flight_mode = "Stabilized";
+		break;
+
+	case vehicle_status_s::NAVIGATION_STATE_RATTITUDE:
+		flight_mode = "Rattitude";
+		break;
+	}
+
+	return crsf_send_telemetry_flight_mode(_uart_fd, flight_mode);
+}

src/drivers/rc_input/crsf_telemetry.h

@@ -0,0 +1,91 @@
+/****************************************************************************
+ *
+ *	Copyright (c) 2018 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 crsf_telemetry.h
+ *
+ * @author Beat Küng <beat-kueng@gmx.net>
+ */
+
+#pragma once
+
+#include <uORB/topics/battery_status.h>
+#include <uORB/topics/vehicle_attitude.h>
+#include <uORB/topics/vehicle_gps_position.h>
+#include <uORB/topics/vehicle_status.h>
+#include <drivers/drv_hrt.h>
+
+#include <matrix/math.hpp>
+#include <mathlib/mathlib.h>
+
+using namespace time_literals;
+
+/**
+ * High-level class that handles sending of CRSF telemetry data
+ */
+class CRSFTelemetry
+{
+public:
+	/**
+	 * @param uart_fd file descriptor for the UART to use. It is expected to be configured
+	 * already.
+	 */
+	CRSFTelemetry(int uart_fd);
+
+	~CRSFTelemetry();
+
+	/**
+	 * Send telemetry data. Call this regularly (i.e. at 100Hz), it will automatically
+	 * limit the sending rate.
+	 * @return true if new data sent
+	 */
+	bool update(const hrt_abstime &now);
+
+private:
+	bool send_battery();
+	bool send_gps();
+	bool send_attitude();
+	bool send_flight_mode();
+
+	int _vehicle_gps_position_sub;
+	int _battery_status_sub;
+	int _vehicle_attitude_sub;
+	int _vehicle_status_sub;
+
+	hrt_abstime _last_update{0};
+
+	static constexpr int num_data_types{4}; ///< number of different telemetry data types
+	int _next_type{0};
+
+	int _uart_fd;
+};