uorb_converter.c 3.27 KB
/*
 * uorb_converter.c
 *
 *  Created on: Apr 10, 2020
 *      Author: hovergames
 */

#include <string.h>

#include "uorb_converter.h"


/****************************************************************************
 * Private Data
 ****************************************************************************/
int uorb_sub_fd;
px4_pollfd_struct_t fds[1];
int error_counter;
CanardInstance *canard_ins;
int raw_uorb_message_transfer_id;
int fix_message_transfer_id;
int aux_message_transfer_id;
int16_t *gps_raw_uorb_port_id;
int16_t *gps_fix_port_id;
int16_t *gps_aux_port_id;


void uorbConverterInit(CanardInstance *ins, int16_t *raw_uorb_port_id, int16_t *fix_port_id, int16_t *aux_port_id)
{
	canard_ins = ins;

	gps_raw_uorb_port_id = raw_uorb_port_id;
	gps_fix_port_id = fix_port_id;
	gps_aux_port_id = aux_port_id;

	/* subscribe to the uORB topic */
	uorb_sub_fd = orb_subscribe(ORB_ID(sensor_gps));

	orb_set_interval(uorb_sub_fd, 200);

	/* one could wait for multiple topics with this technique, just using one here */
	fds[0].fd = uorb_sub_fd;
	fds[0].events = POLLIN;

	error_counter = 0;
	raw_uorb_message_transfer_id = 0;
	fix_message_transfer_id = 0;
	aux_message_transfer_id = 0;
}

void uorbProcessSub(int timeout_msec)
{
	/* wait for subscriber update of 1 file descriptor for timeout_msec ms */
	int poll_ret = px4_poll(fds, 1, timeout_msec);

	/* handle the poll result */
	if (poll_ret == 0) {
		/* this means none of our providers is giving us data */
	} else if (poll_ret < 0) {
		/* this is seriously bad - should be an emergency */
		if (error_counter < 10 || error_counter % 50 == 0) {
			/* use a counter to prevent flooding (and slowing us down) */
			PX4_ERR("ERROR return value from poll(): %d", poll_ret);
		}

		error_counter++;

	} else {
		if (fds[0].revents & POLLIN) {
			/* obtained data for the first file descriptor */
			struct sensor_gps_s raw;
			/* copy sensors raw data into local buffer */
			orb_copy(ORB_ID(sensor_gps), uorb_sub_fd, &raw);

			CanardMicrosecond transmission_deadline = getMonotonicTimestampUSec() + (uint64_t)(1000ULL * 100ULL);

			// raw uORB sensor_gps message
			if (*gps_raw_uorb_port_id != -1) {

				CanardTransfer transfer = {
					.timestamp_usec = transmission_deadline,      // Zero if transmission deadline is not limited.
					.priority       = CanardPriorityNominal,
					.transfer_kind  = CanardTransferKindMessage,
					.port_id        = *gps_raw_uorb_port_id,                       // This is the subject-ID.
					.remote_node_id = CANARD_NODE_ID_UNSET,       // Messages cannot be unicast, so use UNSET.
					.transfer_id    = raw_uorb_message_transfer_id,
					.payload_size   = sizeof(struct sensor_gps_s),
					.payload        = &raw,
				};

				++raw_uorb_message_transfer_id;  // The transfer-ID shall be incremented after every transmission on this subject.
				int32_t result = canardTxPush(canard_ins, &transfer);

				if (result < 0) {
					// An error has occurred: either an argument is invalid or we've ran out of memory.
					// It is possible to statically prove that an out-of-memory will never occur for a given application if the
					// heap is sized correctly; for background, refer to the Robson's Proof and the documentation for O1Heap.
					PX4_ERR("canardTxPush error %d", result);
				}
			}


			PX4_INFO("Recv from uORB");
		}
	}
}