PX4-Autopilot/src/drivers/gps/ubx.h

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/**
 * @file ubx.h
 *
 * U-Blox protocol definition. Following u-blox 6/7/8 Receiver Description
 * including Prototol Specification.
 *
 * @author Thomas Gubler <thomasgubler@student.ethz.ch>
 * @author Julian Oes <joes@student.ethz.ch>
 * @author Anton Babushkin <anton.babushkin@me.com>
 *
 * @author Hannes Delago
 *   (rework, add ubx7+ compatibility)
 *
 */

#ifndef UBX_H_
#define UBX_H_

#include "gps_helper.h"

#define UBX_SYNC1 0xB5
#define UBX_SYNC2 0x62

/* Message Classes */
#define UBX_CLASS_NAV		0x01
#define UBX_CLASS_ACK		0x05
#define UBX_CLASS_CFG		0x06
#define UBX_CLASS_MON		0x0A

/* Message IDs */
#define UBX_ID_NAV_POSLLH	0x02
#define UBX_ID_NAV_SOL		0x06
#define UBX_ID_NAV_PVT		0x07
#define UBX_ID_NAV_VELNED	0x12
#define UBX_ID_NAV_TIMEUTC	0x21
#define UBX_ID_NAV_SVINFO	0x30
#define UBX_ID_ACK_NAK		0x00
#define UBX_ID_ACK_ACK		0x01
#define UBX_ID_CFG_PRT		0x00
#define UBX_ID_CFG_MSG		0x01
#define UBX_ID_CFG_RATE		0x08
#define UBX_ID_CFG_NAV5		0x24
#define UBX_ID_CFG_SBAS		0x16
#define UBX_ID_MON_VER		0x04
#define UBX_ID_MON_HW		0x09

/* Message Classes & IDs */
#define UBX_MSG_NAV_POSLLH	((UBX_CLASS_NAV) | UBX_ID_NAV_POSLLH << 8)
#define UBX_MSG_NAV_SOL		((UBX_CLASS_NAV) | UBX_ID_NAV_SOL << 8)
#define UBX_MSG_NAV_PVT		((UBX_CLASS_NAV) | UBX_ID_NAV_PVT << 8)
#define UBX_MSG_NAV_VELNED	((UBX_CLASS_NAV) | UBX_ID_NAV_VELNED << 8)
#define UBX_MSG_NAV_TIMEUTC	((UBX_CLASS_NAV) | UBX_ID_NAV_TIMEUTC << 8)
#define UBX_MSG_NAV_SVINFO	((UBX_CLASS_NAV) | UBX_ID_NAV_SVINFO << 8)
#define UBX_MSG_ACK_NAK		((UBX_CLASS_ACK) | UBX_ID_ACK_NAK << 8)
#define UBX_MSG_ACK_ACK		((UBX_CLASS_ACK) | UBX_ID_ACK_ACK << 8)
#define UBX_MSG_CFG_PRT		((UBX_CLASS_CFG) | UBX_ID_CFG_PRT << 8)
#define UBX_MSG_CFG_MSG		((UBX_CLASS_CFG) | UBX_ID_CFG_MSG << 8)
#define UBX_MSG_CFG_RATE	((UBX_CLASS_CFG) | UBX_ID_CFG_RATE << 8)
#define UBX_MSG_CFG_NAV5	((UBX_CLASS_CFG) | UBX_ID_CFG_NAV5 << 8)
#define UBX_MSG_CFG_SBAS	((UBX_CLASS_CFG) | UBX_ID_CFG_SBAS << 8)
#define UBX_MSG_MON_HW		((UBX_CLASS_MON) | UBX_ID_MON_HW << 8)
#define UBX_MSG_MON_VER		((UBX_CLASS_MON) | UBX_ID_MON_VER << 8)

/* RX NAV-PVT message content details */
/*   Bitfield "valid" masks */
#define UBX_RX_NAV_PVT_VALID_VALIDDATE		0x01	/**< validDate (Valid UTC Date) */
#define UBX_RX_NAV_PVT_VALID_VALIDTIME		0x02	/**< validTime (Valid UTC Time) */
#define UBX_RX_NAV_PVT_VALID_FULLYRESOLVED	0x04	/**< fullyResolved (1 = UTC Time of Day has been fully resolved (no seconds uncertainty)) */

/*   Bitfield "flags" masks */
#define UBX_RX_NAV_PVT_FLAGS_GNSSFIXOK		0x01	/**< gnssFixOK (A valid fix (i.e within DOP & accuracy masks)) */
#define UBX_RX_NAV_PVT_FLAGS_DIFFSOLN		0x02	/**< diffSoln (1 if differential corrections were applied) */
#define UBX_RX_NAV_PVT_FLAGS_PSMSTATE		0x1C	/**< psmState (Power Save Mode state (see Power Management)) */
#define UBX_RX_NAV_PVT_FLAGS_HEADVEHVALID	0x20	/**< headVehValid (Heading of vehicle is valid) */

/* RX NAV-TIMEUTC message content details */
/*   Bitfield "valid" masks */
#define UBX_RX_NAV_TIMEUTC_VALID_VALIDTOW	0x01	/**< validTOW (1 = Valid Time of Week) */
#define UBX_RX_NAV_TIMEUTC_VALID_VALIDKWN	0x02	/**< validWKN (1 = Valid Week Number) */
#define UBX_RX_NAV_TIMEUTC_VALID_VALIDUTC	0x04	/**< validUTC (1 = Valid UTC Time) */
#define UBX_RX_NAV_TIMEUTC_VALID_UTCSTANDARD	0xF0	/**< utcStandard (0..15 = UTC standard identifier) */

/* TX CFG-PRT message contents */
#define UBX_TX_CFG_PRT_PORTID		0x01		/**< UART1 */
#define UBX_TX_CFG_PRT_MODE		0x000008D0	/**< 0b0000100011010000: 8N1 */
#define UBX_TX_CFG_PRT_BAUDRATE		38400		/**< choose 38400 as GPS baudrate */
#define UBX_TX_CFG_PRT_INPROTOMASK	0x01		/**< UBX in */
#define UBX_TX_CFG_PRT_OUTPROTOMASK	0x01		/**< UBX out */

/* TX CFG-RATE message contents */
#define UBX_TX_CFG_RATE_MEASINTERVAL	200		/**< 200ms for 5Hz */
#define UBX_TX_CFG_RATE_NAVRATE		1		/**< cannot be changed */
#define UBX_TX_CFG_RATE_TIMEREF		0		/**< 0: UTC, 1: GPS time */

/* TX CFG-NAV5 message contents */
#define UBX_TX_CFG_NAV5_MASK		0x0005		/**< Only update dynamic model and fix mode */
#define UBX_TX_CFG_NAV5_DYNMODEL	7		/**< 0 Portable, 2 Stationary, 3 Pedestrian, 4 Automotive, 5 Sea, 6 Airborne <1g, 7 Airborne <2g, 8 Airborne <4g */
#define UBX_TX_CFG_NAV5_FIXMODE		2		/**< 1 2D only, 2 3D only, 3 Auto 2D/3D */

/* TX CFG-SBAS message contents */
#define UBX_TX_CFG_SBAS_MODE_ENABLED	1				/**< SBAS enabled */
#define UBX_TX_CFG_SBAS_MODE_DISABLED	0				/**< SBAS disabled */
#define UBX_TX_CFG_SBAS_MODE		UBX_TX_CFG_SBAS_MODE_DISABLED	/**< SBAS enabled or disabled */

/* TX CFG-MSG message contents */
#define UBX_TX_CFG_MSG_RATE1_5HZ	0x01 		/**< {0x00, 0x01, 0x00, 0x00, 0x00, 0x00} the second entry is for UART1 */
#define UBX_TX_CFG_MSG_RATE1_1HZ	0x05		/**< {0x00, 0x05, 0x00, 0x00, 0x00, 0x00} the second entry is for UART1 */
#define UBX_TX_CFG_MSG_RATE1_05HZ	10


/*** u-blox protocol binary message and payload definitions ***/
#pragma pack(push, 1)

/* General: Header */
typedef struct {
	uint8_t		sync1;
	uint8_t		sync2;
	uint16_t	msg;
	uint16_t	length;
} ubx_header_t;

/* General: Checksum */
typedef struct {
	uint8_t		ck_a;
	uint8_t		ck_b;
} ubx_checksum_t ;

/* Rx NAV-POSLLH */
typedef struct {
	uint32_t	iTOW;		/**< GPS Time of Week [ms] */
	int32_t		lon;		/**< Longitude [1e-7 deg] */
	int32_t		lat;		/**< Latitude [1e-7 deg] */
	int32_t		height;		/**< Height above ellipsoid [mm] */
	int32_t		hMSL;		/**< Height above mean sea level [mm] */
	uint32_t	hAcc;  		/**< Horizontal accuracy estimate [mm] */
	uint32_t	vAcc;  		/**< Vertical accuracy estimate [mm] */
} ubx_payload_rx_nav_posllh_t;

/* Rx NAV-SOL */
typedef struct {
	uint32_t	iTOW;		/**< GPS Time of Week [ms] */
	int32_t		fTOW;		/**< Fractional part of iTOW (range: +/-500000) [ns] */
	int16_t		week;		/**< GPS week */
	uint8_t		gpsFix;		/**< GPSfix type: 0 = No fix, 1 = Dead Reckoning only, 2 = 2D fix, 3 = 3d-fix, 4 = GPS + dead reckoning, 5 = time only fix */
	uint8_t		flags;
	int32_t		ecefX;
	int32_t		ecefY;
	int32_t		ecefZ;
	uint32_t	pAcc;
	int32_t		ecefVX;
	int32_t		ecefVY;
	int32_t		ecefVZ;
	uint32_t	sAcc;
	uint16_t	pDOP;
	uint8_t		reserved1;
	uint8_t		numSV;		/**< Number of SVs used in Nav Solution */
	uint32_t	reserved2;
} ubx_payload_rx_nav_sol_t;

/* Rx NAV-PVT (ubx8) */
typedef struct {
	uint32_t	iTOW;		/**< GPS Time of Week [ms] */
	uint16_t	year; 		/**< Year (UTC)*/
	uint8_t		month; 		/**< Month, range 1..12 (UTC) */
	uint8_t		day; 		/**< Day of month, range 1..31 (UTC) */
	uint8_t		hour; 		/**< Hour of day, range 0..23 (UTC) */
	uint8_t		min; 		/**< Minute of hour, range 0..59 (UTC) */
	uint8_t		sec;		/**< Seconds of minute, range 0..60 (UTC) */
	uint8_t		valid; 		/**< Validity flags (see UBX_RX_NAV_PVT_VALID_...) */
	uint32_t	tAcc; 		/**< Time accuracy estimate (UTC) [ns] */
	int32_t		nano;		/**< Fraction of second (UTC) [-1e9...1e9 ns] */
	uint8_t		fixType;	/**< GNSSfix type: 0 = No fix, 1 = Dead Reckoning only, 2 = 2D fix, 3 = 3d-fix, 4 = GNSS + dead reckoning, 5 = time only fix */
	uint8_t		flags;		/**< Fix Status Flags (see UBX_RX_NAV_PVT_FLAGS_...) */
	uint8_t		reserved1;
	uint8_t		numSV;		/**< Number of SVs used in Nav Solution */
	int32_t		lon;		/**< Longitude [1e-7 deg] */
	int32_t		lat;		/**< Latitude [1e-7 deg] */
	int32_t		height;		/**< Height above ellipsoid [mm] */
	int32_t		hMSL;		/**< Height above mean sea level [mm] */
	uint32_t	hAcc;  		/**< Horizontal accuracy estimate [mm] */
	uint32_t	vAcc;  		/**< Vertical accuracy estimate [mm] */
	int32_t		velN;		/**< NED north velocity [mm/s]*/
	int32_t		velE;		/**< NED east velocity [mm/s]*/
	int32_t		velD;		/**< NED down velocity [mm/s]*/
	int32_t		gSpeed;		/**< Ground Speed (2-D) [mm/s] */
	int32_t		headMot;	/**< Heading of motion (2-D) [1e-5 deg] */
	uint32_t	sAcc;		/**< Speed accuracy estimate [mm/s] */
	uint32_t	headAcc;	/**< Heading accuracy estimate (motion and vehicle) [1e-5 deg] */
	uint16_t	pDOP;		/**< Position DOP [0.01] */
	uint16_t	reserved2;
	uint32_t	reserved3;
	int32_t		headVeh;	/**< (ubx8+ only) Heading of vehicle (2-D) [1e-5 deg] */
	uint32_t	reserved4;	/**< (ubx8+ only) */
} ubx_payload_rx_nav_pvt_t;
#define UBX_PAYLOAD_RX_NAV_PVT_SIZE_UBX7	(sizeof(ubx_payload_rx_nav_pvt_t) - 8)
#define UBX_PAYLOAD_RX_NAV_PVT_SIZE_UBX8	(sizeof(ubx_payload_rx_nav_pvt_t))

/* Rx NAV-TIMEUTC */
typedef struct {
	uint32_t	iTOW;		/**< GPS Time of Week [ms] */
	uint32_t	tAcc; 		/**< Time accuracy estimate (UTC) [ns] */
	int32_t		nano;		/**< Fraction of second, range -1e9 .. 1e9 (UTC) [ns] */
	uint16_t	year; 		/**< Year, range 1999..2099 (UTC) */
	uint8_t		month; 		/**< Month, range 1..12 (UTC) */
	uint8_t		day; 		/**< Day of month, range 1..31 (UTC) */
	uint8_t		hour; 		/**< Hour of day, range 0..23 (UTC) */
	uint8_t		min; 		/**< Minute of hour, range 0..59 (UTC) */
	uint8_t		sec;		/**< Seconds of minute, range 0..60 (UTC) */
	uint8_t		valid; 		/**< Validity Flags (see UBX_RX_NAV_TIMEUTC_VALID_...) */
} ubx_payload_rx_nav_timeutc_t;

/* Rx NAV-SVINFO Part 1 */
typedef struct {
	uint32_t	iTOW;		/**< GPS Time of Week [ms] */
	uint8_t		numCh; 		/**< Number of channels */
	uint8_t		globalFlags;
	uint16_t	reserved2;
} ubx_payload_rx_nav_svinfo_part1_t;

/* Rx NAV-SVINFO Part 2 (repeated) */
typedef struct {
	uint8_t		chn; 		/**< Channel number, 255 for SVs not assigned to a channel */
	uint8_t		svid; 		/**< Satellite ID */
	uint8_t		flags;
	uint8_t		quality;
	uint8_t		cno;		/**< Carrier to Noise Ratio (Signal Strength) [dbHz] */
	int8_t		elev; 		/**< Elevation [deg] */
	int16_t		azim; 		/**< Azimuth [deg] */
	int32_t		prRes; 		/**< Pseudo range residual [cm] */
} ubx_payload_rx_nav_svinfo_part2_t;

/* Rx NAV-VELNED */
typedef struct {
	uint32_t	iTOW;		/**< GPS Time of Week [ms] */
	int32_t		velN;		/**< North velocity component [cm/s]*/
	int32_t		velE;		/**< East velocity component [cm/s]*/
	int32_t		velD;		/**< Down velocity component [cm/s]*/
	uint32_t	speed;		/**< Speed (3-D) [cm/s] */
	uint32_t	gSpeed;		/**< Ground speed (2-D) [cm/s] */
	int32_t		heading;	/**< Heading of motion 2-D [1e-5 deg] */
	uint32_t	sAcc;		/**< Speed accuracy estimate [cm/s] */
	uint32_t	cAcc;		/**< Course / Heading accuracy estimate [1e-5 deg] */
} ubx_payload_rx_nav_velned_t;

/* Rx MON-HW (ubx6) */
typedef struct {
	uint32_t	pinSel;
	uint32_t	pinBank;
	uint32_t	pinDir;
	uint32_t	pinVal;
	uint16_t	noisePerMS;
	uint16_t	agcCnt;
	uint8_t		aStatus;
	uint8_t		aPower;
	uint8_t		flags;
	uint8_t		reserved1;
	uint32_t	usedMask;
	uint8_t		VP[25];
	uint8_t		jamInd;
	uint16_t	reserved3;
	uint32_t	pinIrq;
	uint32_t	pullH;
	uint32_t	pullL;
} ubx_payload_rx_mon_hw_ubx6_t;

/* Rx MON-HW (ubx7+) */
typedef struct {
	uint32_t	pinSel;
	uint32_t	pinBank;
	uint32_t	pinDir;
	uint32_t	pinVal;
	uint16_t	noisePerMS;
	uint16_t	agcCnt;
	uint8_t		aStatus;
	uint8_t		aPower;
	uint8_t		flags;
	uint8_t		reserved1;
	uint32_t	usedMask;
	uint8_t		VP[17];
	uint8_t		jamInd;
	uint16_t	reserved3;
	uint32_t	pinIrq;
	uint32_t	pullH;
	uint32_t	pullL;
} ubx_payload_rx_mon_hw_ubx7_t;

/* Rx MON-VER Part 1 */
typedef struct {
	uint8_t		swVersion[30];
	uint8_t		hwVersion[10];
} ubx_payload_rx_mon_ver_part1_t;

/* Rx MON-VER Part 2 (repeated) */
typedef struct {
	uint8_t		extension[30];
} ubx_payload_rx_mon_ver_part2_t;

/* Rx ACK-ACK */
typedef	union {
	uint16_t	msg;
	struct {
		uint8_t	clsID;
		uint8_t	msgID;
	};
} ubx_payload_rx_ack_ack_t;

/* Rx ACK-NAK */
typedef	union {
	uint16_t	msg;
	struct {
		uint8_t	clsID;
		uint8_t	msgID;
	};
} ubx_payload_rx_ack_nak_t;

/* Tx CFG-PRT */
typedef struct {
	uint8_t		portID;
	uint8_t		reserved0;
	uint16_t	txReady;
	uint32_t	mode;
	uint32_t	baudRate;
	uint16_t	inProtoMask;
	uint16_t	outProtoMask;
	uint16_t	flags;
	uint16_t	reserved5;
} ubx_payload_tx_cfg_prt_t;

/* Tx CFG-RATE */
typedef struct {
	uint16_t	measRate;	/**< Measurement Rate, GPS measurements are taken every measRate milliseconds */
	uint16_t	navRate;	/**< Navigation Rate, in number of measurement cycles. This parameter cannot be changed, and must be set to 1 */
	uint16_t	timeRef;	/**< Alignment to reference time: 0 = UTC time, 1 = GPS time */
} ubx_payload_tx_cfg_rate_t;

/* Tx CFG-NAV5 */
typedef struct {
	uint16_t	mask;
	uint8_t		dynModel;	/**< Dynamic Platform model: 0 Portable, 2 Stationary, 3 Pedestrian, 4 Automotive, 5 Sea, 6 Airborne <1g, 7 Airborne <2g, 8 Airborne <4g */
	uint8_t		fixMode;	/**< Position Fixing Mode: 1 2D only, 2 3D only, 3 Auto 2D/3D */
	int32_t		fixedAlt;
	uint32_t	fixedAltVar;
	int8_t		minElev;
	uint8_t		drLimit;
	uint16_t	pDop;
	uint16_t	tDop;
	uint16_t	pAcc;
	uint16_t	tAcc;
	uint8_t		staticHoldThresh;
	uint8_t		dgpsTimeOut;
	uint8_t		cnoThreshNumSVs;	/**< (ubx7+ only, else 0) */
	uint8_t		cnoThresh;		/**< (ubx7+ only, else 0) */
	uint16_t	reserved;
	uint16_t	staticHoldMaxDist;	/**< (ubx8+ only, else 0) */
	uint8_t		utcStandard;		/**< (ubx8+ only, else 0) */
	uint8_t		reserved3;
	uint32_t	reserved4;
} ubx_payload_tx_cfg_nav5_t;

/* tx cfg-sbas */
typedef struct {
	uint8_t		mode;
	uint8_t		usage;
	uint8_t		maxSBAS;
	uint8_t		scanmode2;
	uint32_t	scanmode1;
} ubx_payload_tx_cfg_sbas_t;

/* Tx CFG-MSG */
typedef struct {
	union {
		uint16_t	msg;
		struct {
			uint8_t	msgClass;
			uint8_t	msgID;
		};
	};
	uint8_t rate;
} ubx_payload_tx_cfg_msg_t;

/* General message and payload buffer union */
typedef union {
	ubx_payload_rx_nav_pvt_t		payload_rx_nav_pvt;
	ubx_payload_rx_nav_posllh_t		payload_rx_nav_posllh;
	ubx_payload_rx_nav_sol_t		payload_rx_nav_sol;
	ubx_payload_rx_nav_timeutc_t		payload_rx_nav_timeutc;
	ubx_payload_rx_nav_svinfo_part1_t	payload_rx_nav_svinfo_part1;
	ubx_payload_rx_nav_svinfo_part2_t	payload_rx_nav_svinfo_part2;
	ubx_payload_rx_nav_velned_t		payload_rx_nav_velned;
	ubx_payload_rx_mon_hw_ubx6_t		payload_rx_mon_hw_ubx6;
	ubx_payload_rx_mon_hw_ubx7_t		payload_rx_mon_hw_ubx7;
	ubx_payload_rx_mon_ver_part1_t		payload_rx_mon_ver_part1;
	ubx_payload_rx_mon_ver_part2_t		payload_rx_mon_ver_part2;
	ubx_payload_rx_ack_ack_t		payload_rx_ack_ack;
	ubx_payload_rx_ack_nak_t		payload_rx_ack_nak;
	ubx_payload_tx_cfg_prt_t		payload_tx_cfg_prt;
	ubx_payload_tx_cfg_rate_t		payload_tx_cfg_rate;
	ubx_payload_tx_cfg_nav5_t		payload_tx_cfg_nav5;
	ubx_payload_tx_cfg_sbas_t		payload_tx_cfg_sbas;
	ubx_payload_tx_cfg_msg_t		payload_tx_cfg_msg;
	uint8_t					raw[];
} ubx_buf_t;

#pragma pack(pop)
/*** END OF u-blox protocol binary message and payload definitions ***/

/* Decoder state */
typedef enum {
	UBX_DECODE_SYNC1 = 0,
	UBX_DECODE_SYNC2,
	UBX_DECODE_CLASS,
	UBX_DECODE_ID,
	UBX_DECODE_LENGTH1,
	UBX_DECODE_LENGTH2,
	UBX_DECODE_PAYLOAD,
	UBX_DECODE_CHKSUM1,
	UBX_DECODE_CHKSUM2
} ubx_decode_state_t;

/* Rx message state */
typedef enum {
	UBX_RXMSG_IGNORE = 0,
	UBX_RXMSG_HANDLE,
	UBX_RXMSG_DISABLE,
	UBX_RXMSG_ERROR_LENGTH
} ubx_rxmsg_state_t;

/* ACK state */
typedef enum {
	UBX_ACK_IDLE = 0,
	UBX_ACK_WAITING,
	UBX_ACK_GOT_ACK,
	UBX_ACK_GOT_NAK
} ubx_ack_state_t;


class UBX : public GPS_Helper
{
public:
	UBX(const int &fd, struct vehicle_gps_position_s *gps_position, struct satellite_info_s *satellite_info);
	~UBX();
	int			receive(const unsigned timeout);
	int			configure(unsigned &baudrate);

private:

	/**
	 * Parse the binary UBX packet
	 */
	int			parse_char(const uint8_t b);

	/**
	 * Start payload rx
	 */
	int			payload_rx_init(void);

	/**
	 * Add payload rx byte
	 */
	int			payload_rx_add(const uint8_t b);
	int			payload_rx_add_nav_svinfo(const uint8_t b);
	int			payload_rx_add_mon_ver(const uint8_t b);

	/**
	 * Finish payload rx
	 */
	int			payload_rx_done(void);

	/**
	 * Reset the parse state machine for a fresh start
	 */
	void			decode_init(void);

	/**
	 * While parsing add every byte (except the sync bytes) to the checksum
	 */
	void			add_byte_to_checksum(const uint8_t);

	/**
	 * Send a message
	 */
	void			send_message(const uint16_t msg, const uint8_t *payload, const uint16_t length);

	/**
	 * Configure message rate
	 */
	void			configure_message_rate(const uint16_t msg, const uint8_t rate);

	/**
	 * Calculate & add checksum for given buffer
	 */
	void			calc_checksum(const uint8_t *buffer, const uint16_t length, ubx_checksum_t *checksum);

	/**
	 * Wait for message acknowledge
	 */
	int			wait_for_ack(const uint16_t msg, const unsigned timeout, const bool report);

	/**
	 * Calculate FNV1 hash
	 */
	uint32_t		fnv1_32_str(uint8_t *str, uint32_t hval);

	int			_fd;
	struct vehicle_gps_position_s *_gps_position;
	struct satellite_info_s *_satellite_info;
	bool			_enable_sat_info;
	bool			_configured;
	ubx_ack_state_t		_ack_state;
	bool			_got_posllh;
	bool			_got_velned;
	ubx_decode_state_t	_decode_state;
	uint16_t		_rx_msg;
	ubx_rxmsg_state_t	_rx_state;
	uint16_t		_rx_payload_length;
	uint16_t		_rx_payload_index;
	uint8_t			_rx_ck_a;
	uint8_t			_rx_ck_b;
	hrt_abstime		_disable_cmd_last;
	uint16_t		_ack_waiting_msg;
	ubx_buf_t		_buf;
	uint32_t		_ubx_version;
	bool			_use_nav_pvt;
};

#endif /* UBX_H_ */