Exemplo n.º 1
0
void
controls_tick() {

	/*
	 * Gather R/C control inputs from supported sources.
	 *
	 * Note that if you're silly enough to connect more than
	 * one control input source, they're going to fight each
	 * other.  Don't do that.
	 */

	/* receive signal strenght indicator (RSSI). 0 = no connection, 255: perfect connection */
	uint16_t rssi = 0;

#ifdef ADC_RSSI
	if (r_setup_features & PX4IO_P_SETUP_FEATURES_ADC_RSSI) {
		unsigned counts = adc_measure(ADC_RSSI);
		if (counts != 0xffff) {
			/* use 1:1 scaling on 3.3V ADC input */
			unsigned mV = counts * 3300 / 4096;

			/* scale to 0..253 */
			rssi = mV / 13;
		}
	}
#endif

	perf_begin(c_gather_dsm);
	uint16_t temp_count = r_raw_rc_count;
	bool dsm_updated = dsm_input(r_raw_rc_values, &temp_count);
	if (dsm_updated) {
		r_raw_rc_flags |= PX4IO_P_STATUS_FLAGS_RC_DSM;
		r_raw_rc_count = temp_count & 0x7fff;
		if (temp_count & 0x8000)
			r_raw_rc_flags |= PX4IO_P_RAW_RC_FLAGS_RC_DSM11;
		else
			r_raw_rc_flags &= ~PX4IO_P_RAW_RC_FLAGS_RC_DSM11;

		r_raw_rc_flags &= ~(PX4IO_P_RAW_RC_FLAGS_FRAME_DROP);
		r_raw_rc_flags &= ~(PX4IO_P_RAW_RC_FLAGS_FAILSAFE);

	}
	perf_end(c_gather_dsm);

	perf_begin(c_gather_sbus);

	bool sbus_status = (r_status_flags & PX4IO_P_STATUS_FLAGS_RC_SBUS);

	bool sbus_failsafe, sbus_frame_drop;
	bool sbus_updated = sbus_input(r_raw_rc_values, &r_raw_rc_count, &sbus_failsafe, &sbus_frame_drop, PX4IO_RC_INPUT_CHANNELS);

	if (sbus_updated) {
		r_status_flags |= PX4IO_P_STATUS_FLAGS_RC_SBUS;

		rssi = 255;

		if (sbus_frame_drop) {
			r_raw_rc_flags |= PX4IO_P_RAW_RC_FLAGS_FRAME_DROP;
			rssi = 100;
		} else {
			r_raw_rc_flags &= ~(PX4IO_P_RAW_RC_FLAGS_FRAME_DROP);
		}

		if (sbus_failsafe) {
			r_raw_rc_flags |= PX4IO_P_RAW_RC_FLAGS_FAILSAFE;
			rssi = 0;
		} else {
			r_raw_rc_flags &= ~(PX4IO_P_RAW_RC_FLAGS_FAILSAFE);
		}

	}

	perf_end(c_gather_sbus);

	/*
	 * XXX each S.bus frame will cause a PPM decoder interrupt
	 * storm (lots of edges).  It might be sensible to actually
	 * disable the PPM decoder completely if we have S.bus signal.
	 */
	perf_begin(c_gather_ppm);
	bool ppm_updated = ppm_input(r_raw_rc_values, &r_raw_rc_count, &r_page_raw_rc_input[PX4IO_P_RAW_RC_DATA]);
	if (ppm_updated) {

		r_status_flags |= PX4IO_P_STATUS_FLAGS_RC_PPM;
		r_raw_rc_flags &= ~(PX4IO_P_RAW_RC_FLAGS_FRAME_DROP);
		r_raw_rc_flags &= ~(PX4IO_P_RAW_RC_FLAGS_FAILSAFE);
	}
	perf_end(c_gather_ppm);

	/* limit number of channels to allowable data size */
	if (r_raw_rc_count > PX4IO_RC_INPUT_CHANNELS)
		r_raw_rc_count = PX4IO_RC_INPUT_CHANNELS;

	/* store RSSI */
	r_page_raw_rc_input[PX4IO_P_RAW_RC_NRSSI] = rssi;

	/*
	 * In some cases we may have received a frame, but input has still
	 * been lost.
	 */
	bool rc_input_lost = false;

	/*
	 * If we received a new frame from any of the RC sources, process it.
	 */
	if (dsm_updated || sbus_updated || ppm_updated) {

		/* record a bitmask of channels assigned */
		unsigned assigned_channels = 0;

		/* update RC-received timestamp */
		system_state.rc_channels_timestamp_received = hrt_absolute_time();

		/* do not command anything in failsafe, kick in the RC loss counter */
		if (!(r_raw_rc_flags & PX4IO_P_RAW_RC_FLAGS_FAILSAFE)) {

			/* update RC-received timestamp */
			system_state.rc_channels_timestamp_valid = system_state.rc_channels_timestamp_received;

			/* map raw inputs to mapped inputs */
			/* XXX mapping should be atomic relative to protocol */
			for (unsigned i = 0; i < r_raw_rc_count; i++) {

				/* map the input channel */
				uint16_t *conf = &r_page_rc_input_config[i * PX4IO_P_RC_CONFIG_STRIDE];

				if (conf[PX4IO_P_RC_CONFIG_OPTIONS] & PX4IO_P_RC_CONFIG_OPTIONS_ENABLED) {

					uint16_t raw = r_raw_rc_values[i];

					int16_t scaled;

					/*
					 * 1) Constrain to min/max values, as later processing depends on bounds.
					 */
					if (raw < conf[PX4IO_P_RC_CONFIG_MIN])
						raw = conf[PX4IO_P_RC_CONFIG_MIN];
					if (raw > conf[PX4IO_P_RC_CONFIG_MAX])
						raw = conf[PX4IO_P_RC_CONFIG_MAX];

					/*
					 * 2) Scale around the mid point differently for lower and upper range.
					 *
					 * This is necessary as they don't share the same endpoints and slope.
					 *
					 * First normalize to 0..1 range with correct sign (below or above center),
					 * then scale to 20000 range (if center is an actual center, -10000..10000,
					 * if parameters only support half range, scale to 10000 range, e.g. if
					 * center == min 0..10000, if center == max -10000..0).
					 *
					 * As the min and max bounds were enforced in step 1), division by zero
					 * cannot occur, as for the case of center == min or center == max the if
					 * statement is mutually exclusive with the arithmetic NaN case.
					 *
					 * DO NOT REMOVE OR ALTER STEP 1!
					 */
					if (raw > (conf[PX4IO_P_RC_CONFIG_CENTER] + conf[PX4IO_P_RC_CONFIG_DEADZONE])) {
						scaled = 10000.0f * ((raw - conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE]) / (float)(conf[PX4IO_P_RC_CONFIG_MAX] - conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE]));

					} else if (raw < (conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE])) {
						scaled = 10000.0f * ((raw - conf[PX4IO_P_RC_CONFIG_CENTER] + conf[PX4IO_P_RC_CONFIG_DEADZONE]) / (float)(conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE] - conf[PX4IO_P_RC_CONFIG_MIN]));

					} else {
						/* in the configured dead zone, output zero */
						scaled = 0;
					}

					/* invert channel if requested */
					if (conf[PX4IO_P_RC_CONFIG_OPTIONS] & PX4IO_P_RC_CONFIG_OPTIONS_REVERSE)
						scaled = -scaled;

					/* and update the scaled/mapped version */
					unsigned mapped = conf[PX4IO_P_RC_CONFIG_ASSIGNMENT];
					if (mapped < PX4IO_CONTROL_CHANNELS) {

						/* invert channel if pitch - pulling the lever down means pitching up by convention */
						if (mapped == 1) /* roll, pitch, yaw, throttle, override is the standard order */
							scaled = -scaled;

						r_rc_values[mapped] = SIGNED_TO_REG(scaled);
						assigned_channels |= (1 << mapped);

					}
				}
			}

			/* set un-assigned controls to zero */
			for (unsigned i = 0; i < PX4IO_CONTROL_CHANNELS; i++) {
				if (!(assigned_channels & (1 << i)))
					r_rc_values[i] = 0;
			}

			/* set RC OK flag, as we got an update */
			r_status_flags |= PX4IO_P_STATUS_FLAGS_RC_OK;

			/* if we have enough channels (5) to control the vehicle, the mapping is ok */
			if (assigned_channels > 4) {
				r_raw_rc_flags |= PX4IO_P_RAW_RC_FLAGS_MAPPING_OK;
			} else {
				r_raw_rc_flags &= ~(PX4IO_P_RAW_RC_FLAGS_MAPPING_OK);
			}
		}

		/*
		 * Export the valid channel bitmap
		 */
		r_rc_valid = assigned_channels;
	}

	/*
	 * If we haven't seen any new control data in 200ms, assume we
	 * have lost input.
	 */
	if (hrt_elapsed_time(&system_state.rc_channels_timestamp_received) > 200000) {
		rc_input_lost = true;

		/* clear the input-kind flags here */
		r_status_flags &= ~(
			PX4IO_P_STATUS_FLAGS_RC_PPM |
			PX4IO_P_STATUS_FLAGS_RC_DSM |
			PX4IO_P_STATUS_FLAGS_RC_SBUS);

	}

	/*
	 * Handle losing RC input
	 */

	/* this kicks in if the receiver is gone or the system went to failsafe */
	if (rc_input_lost || (r_raw_rc_flags & PX4IO_P_RAW_RC_FLAGS_FAILSAFE)) {
		/* Clear the RC input status flag, clear manual override flag */
		r_status_flags &= ~(
			PX4IO_P_STATUS_FLAGS_OVERRIDE |
			PX4IO_P_STATUS_FLAGS_RC_OK);

		/* Mark all channels as invalid, as we just lost the RX */
		r_rc_valid = 0;

		/* Set the RC_LOST alarm */
		r_status_alarms |= PX4IO_P_STATUS_ALARMS_RC_LOST;
	}

	/* this kicks in if the receiver is completely gone */
	if (rc_input_lost) {

		/* Set channel count to zero */
		r_raw_rc_count = 0;
	}

	/*
	 * Check for manual override.
	 *
	 * The PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK flag must be set, and we
	 * must have R/C input.
	 * Override is enabled if either the hardcoded channel / value combination
	 * is selected, or the AP has requested it.
	 */
	if ((r_setup_arming & PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK) && 
		(r_status_flags & PX4IO_P_STATUS_FLAGS_RC_OK)) {

		bool override = false;

		/*
		 * Check mapped channel 5 (can be any remote channel,
		 * depends on RC_MAP_OVER parameter);
		 * If the value is 'high' then the pilot has
		 * requested override.
		 *
		 */
		if ((r_status_flags & PX4IO_P_STATUS_FLAGS_RC_OK) && (REG_TO_SIGNED(r_rc_values[4]) < RC_CHANNEL_LOW_THRESH))
			override = true;

		if (override) {

			r_status_flags |= PX4IO_P_STATUS_FLAGS_OVERRIDE;

			/* mix new RC input control values to servos */
			if (dsm_updated || sbus_updated || ppm_updated)
				mixer_tick();

		} else {
Exemplo n.º 2
0
void
controls_tick() {

	/*
	 * Gather R/C control inputs from supported sources.
	 *
	 * Note that if you're silly enough to connect more than
	 * one control input source, they're going to fight each
	 * other.  Don't do that.
	 */

	perf_begin(c_gather_dsm);
	bool dsm_updated = dsm_input(r_raw_rc_values, &r_raw_rc_count);
	if (dsm_updated)
		r_status_flags |= PX4IO_P_STATUS_FLAGS_RC_DSM;
	perf_end(c_gather_dsm);

	perf_begin(c_gather_sbus);
	bool sbus_updated = sbus_input(r_raw_rc_values, &r_raw_rc_count);
	if (sbus_updated)
		r_status_flags |= PX4IO_P_STATUS_FLAGS_RC_SBUS;
	perf_end(c_gather_sbus);

	/*
	 * XXX each S.bus frame will cause a PPM decoder interrupt
	 * storm (lots of edges).  It might be sensible to actually
	 * disable the PPM decoder completely if we have S.bus signal.
	 */
	perf_begin(c_gather_ppm);
	bool ppm_updated = ppm_input(r_raw_rc_values, &r_raw_rc_count);
	if (ppm_updated)
		r_status_flags |= PX4IO_P_STATUS_FLAGS_RC_PPM;
	perf_end(c_gather_ppm);

	ASSERT(r_raw_rc_count <= MAX_CONTROL_CHANNELS);

	/*
	 * In some cases we may have received a frame, but input has still
	 * been lost.
	 */
	bool rc_input_lost = false;

	/*
	 * If we received a new frame from any of the RC sources, process it.
	 */
	if (dsm_updated || sbus_updated || ppm_updated) {

		/* update RC-received timestamp */
		system_state.rc_channels_timestamp = hrt_absolute_time();

		/* record a bitmask of channels assigned */
		unsigned assigned_channels = 0;

		/* map raw inputs to mapped inputs */
		/* XXX mapping should be atomic relative to protocol */
		for (unsigned i = 0; i < r_raw_rc_count; i++) {

			/* map the input channel */
			uint16_t *conf = &r_page_rc_input_config[i * PX4IO_P_RC_CONFIG_STRIDE];

			if (conf[PX4IO_P_RC_CONFIG_OPTIONS] & PX4IO_P_RC_CONFIG_OPTIONS_ENABLED) {

				uint16_t raw = r_raw_rc_values[i];

				int16_t scaled;

				/*
				 * 1) Constrain to min/max values, as later processing depends on bounds.
				 */
				if (raw < conf[PX4IO_P_RC_CONFIG_MIN])
					raw = conf[PX4IO_P_RC_CONFIG_MIN];
				if (raw > conf[PX4IO_P_RC_CONFIG_MAX])
					raw = conf[PX4IO_P_RC_CONFIG_MAX];

				/*
				 * 2) Scale around the mid point differently for lower and upper range.
				 *
				 * This is necessary as they don't share the same endpoints and slope.
				 *
				 * First normalize to 0..1 range with correct sign (below or above center),
				 * then scale to 20000 range (if center is an actual center, -10000..10000,
				 * if parameters only support half range, scale to 10000 range, e.g. if
				 * center == min 0..10000, if center == max -10000..0).
				 *
				 * As the min and max bounds were enforced in step 1), division by zero
				 * cannot occur, as for the case of center == min or center == max the if
				 * statement is mutually exclusive with the arithmetic NaN case.
				 *
				 * DO NOT REMOVE OR ALTER STEP 1!
				 */
				if (raw > (conf[PX4IO_P_RC_CONFIG_CENTER] + conf[PX4IO_P_RC_CONFIG_DEADZONE])) {
					scaled = 10000.0f * ((raw - conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE]) / (float)(conf[PX4IO_P_RC_CONFIG_MAX] - conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE]));

				} else if (raw < (conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE])) {
					scaled = 10000.0f * ((raw - conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE]) / (float)(conf[PX4IO_P_RC_CONFIG_CENTER] - conf[PX4IO_P_RC_CONFIG_DEADZONE] - conf[PX4IO_P_RC_CONFIG_MIN]));

				} else {
					/* in the configured dead zone, output zero */
					scaled = 0;
				}

				/* invert channel if requested */
				if (conf[PX4IO_P_RC_CONFIG_OPTIONS] & PX4IO_P_RC_CONFIG_OPTIONS_REVERSE)
					scaled = -scaled;

				/* and update the scaled/mapped version */
				unsigned mapped = conf[PX4IO_P_RC_CONFIG_ASSIGNMENT];
				ASSERT(mapped < MAX_CONTROL_CHANNELS);

				/* invert channel if pitch - pulling the lever down means pitching up by convention */
				if (mapped == 1) /* roll, pitch, yaw, throttle, override is the standard order */
					scaled = -scaled;

				r_rc_values[mapped] = SIGNED_TO_REG(scaled);
				assigned_channels |= (1 << mapped);
			}
		}

		/* set un-assigned controls to zero */
		for (unsigned i = 0; i < MAX_CONTROL_CHANNELS; i++) {
			if (!(assigned_channels & (1 << i)))
				r_rc_values[i] = 0;
		}

		/*
		 * If we got an update with zero channels, treat it as 
		 * a loss of input.
		 *
		 * This might happen if a protocol-based receiver returns an update
		 * that contains no channels that we have mapped.
		 */
		if (assigned_channels == 0) {
			rc_input_lost = true;
		} else {
			/* set RC OK flag and clear RC lost alarm */
			r_status_flags |= PX4IO_P_STATUS_FLAGS_RC_OK;
			r_status_alarms &= ~PX4IO_P_STATUS_ALARMS_RC_LOST;
		}

		/*
		 * Export the valid channel bitmap
		 */
		r_rc_valid = assigned_channels;
	}

	/*
	 * If we haven't seen any new control data in 200ms, assume we
	 * have lost input.
	 */
	if (hrt_elapsed_time(&system_state.rc_channels_timestamp) > 200000) {
		rc_input_lost = true;

		/* clear the input-kind flags here */
		r_status_flags &= ~(
			PX4IO_P_STATUS_FLAGS_RC_PPM |
			PX4IO_P_STATUS_FLAGS_RC_DSM |
			PX4IO_P_STATUS_FLAGS_RC_SBUS);
	}

	/*
	 * Handle losing RC input
	 */
	if (rc_input_lost) {

		/* Clear the RC input status flag, clear manual override flag */
		r_status_flags &= ~(
			PX4IO_P_STATUS_FLAGS_OVERRIDE |
			PX4IO_P_STATUS_FLAGS_RC_OK);

		/* Set the RC_LOST alarm */
		r_status_alarms |= PX4IO_P_STATUS_ALARMS_RC_LOST;

		/* Mark the arrays as empty */
		r_raw_rc_count = 0;
		r_rc_valid = 0;
	}

	/*
	 * Check for manual override.
	 *
	 * The PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK flag must be set, and we
	 * must have R/C input.
	 * Override is enabled if either the hardcoded channel / value combination
	 * is selected, or the AP has requested it.
	 */
	if ((r_setup_arming & PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK) && 
		(r_status_flags & PX4IO_P_STATUS_FLAGS_RC_OK)) {

		bool override = false;

		/*
		 * Check mapped channel 5 (can be any remote channel,
		 * depends on RC_MAP_OVER parameter);
		 * If the value is 'high' then the pilot has
		 * requested override.
		 *
		 */
		if ((r_status_flags & PX4IO_P_STATUS_FLAGS_RC_OK) && (REG_TO_SIGNED(r_rc_values[4]) > RC_CHANNEL_HIGH_THRESH))
			override = true;

		if (override) {

			r_status_flags |= PX4IO_P_STATUS_FLAGS_OVERRIDE;

			/* mix new RC input control values to servos */
			if (dsm_updated || sbus_updated || ppm_updated)
				mixer_tick();

		} else {