UBX.h

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/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, see <http://www.gnu.org/licenses/>
 */

#ifndef UBX_H
#define UBX_H
#include "openpilot.h"
#include "gpsposition.h"
#include "GPS.h"


#define UBX_SYNC1                                               0xb5 // UBX protocol synchronization characters
#define UBX_SYNC2                                               0x62

// From u-blox6 receiver protocol specification

// Messages classes
#define UBX_CLASS_NAV   0x01

// Message IDs (all in NAV class)
#define UBX_ID_POSLLH   0x02
#define UBX_ID_STATUS   0x03
#define UBX_ID_DOP              0x04
#define UBX_ID_SOL              0x06
#define UBX_ID_VELNED   0x12
#define UBX_ID_TIMEUTC  0x21
#define UBX_ID_SVINFO   0x30

#define UBX_CLASS_MON   0x0A

#define UBX_ID_MONVER   0x04
// private structures

// Geodetic Position Solution
struct UBX_NAV_POSLLH {
        uint32_t        iTOW;   // GPS Millisecond Time of Week (ms)
        int32_t         lon;    // Longitude (deg*1e-7)
        int32_t         lat;    // Latitude (deg*1e-7)
        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)
};

// Receiver Navigation Status

#define STATUS_GPSFIX_NOFIX             0x00
#define STATUS_GPSFIX_DRONLY    0x01
#define STATUS_GPSFIX_2DFIX             0x02
#define STATUS_GPSFIX_3DFIX             0x03
#define STATUS_GPSFIX_GPSDR             0x04
#define STATUS_GPSFIX_TIMEONLY  0x05

#define STATUS_FLAGS_GPSFIX_OK  (1 << 0)
#define STATUS_FLAGS_DIFFSOLN   (1 << 1)
#define STATUS_FLAGS_WKNSET             (1 << 2)
#define STATUS_FLAGS_TOWSET             (1 << 3)

struct UBX_NAV_STATUS {
        uint32_t        iTOW;    // GPS Millisecond Time of Week (ms)
        uint8_t         gpsFix;  // GPS fix type
        uint8_t         flags;   // Navigation Status Flags
        uint8_t         fixStat; // Fix Status Information
        uint8_t         flags2;  // Additional navigation output information
        uint32_t        ttff;    // Time to first fix (ms)
        uint32_t        msss;    // Milliseconds since startup/reset (ms)
};

// Dilution of precision
struct UBX_NAV_DOP {
        uint32_t        iTOW;  // GPS Millisecond Time of Week (ms)
        uint16_t        gDOP;  // Geometric DOP
        uint16_t        pDOP;  // Position DOP
        uint16_t        tDOP;  // Time DOP
        uint16_t        vDOP;  // Vertical DOP
        uint16_t        hDOP;  // Horizontal DOP
        uint16_t        nDOP;  // Northing DOP
        uint16_t        eDOP;  // Easting DOP
};

// Navigation solution

struct UBX_NAV_SOL {
        uint32_t        iTOW;       // GPS Millisecond Time of Week (ms)
        int32_t         fTOW;       // fractional nanoseconds (ns)
        int16_t         week;       // GPS week
        uint8_t         gpsFix;     // GPS fix type
        uint8_t         flags;      // Fix status flags
        int32_t         ecefX;      // ECEF X coordinate (cm)
        int32_t         ecefY;      // ECEF Y coordinate (cm)
        int32_t         ecefZ;      // ECEF Z coordinate (cm)
        uint32_t        pAcc;       // 3D Position Accuracy Estimate (cm)
        int32_t         ecefVX;     // ECEF X coordinate (cm/s)
        int32_t         ecefVY;     // ECEF Y coordinate (cm/s)
        int32_t         ecefVZ;     // ECEF Z coordinate (cm/s)
        uint32_t        sAcc;       // Speed Accuracy Estimate
        uint16_t        pDOP;       // Position DOP
        uint8_t         reserved1;  // Reserved
        uint8_t         numSV;      // Number of SVs used in Nav Solution
        uint32_t        reserved2;  // Reserved
};

// North/East/Down velocity

struct UBX_NAV_VELNED {
        uint32_t        iTOW;     // ms GPS Millisecond Time of Week
        int32_t         velN;     // cm/s NED north velocity
        int32_t         velE;     // cm/s NED east velocity
        int32_t         velD;     // cm/s NED down velocity
        uint32_t        speed;    // cm/s Speed (3-D)
        uint32_t        gSpeed;   // cm/s Ground Speed (2-D)
        int32_t         heading;  // 1e-5 *deg Heading of motion 2-D
        uint32_t        sAcc;     // cm/s Speed Accuracy Estimate
        uint32_t        cAcc;     // 1e-5 *deg Course / Heading Accuracy Estimate
};

// UTC Time Solution

#define TIMEUTC_VALIDTOW        (1 << 0)
#define TIMEUTC_VALIDWKN        (1 << 1)
#define TIMEUTC_VALIDUTC        (1 << 2)

struct UBX_NAV_TIMEUTC {
        uint32_t        iTOW;   // GPS Millisecond Time of Week (ms)
        uint32_t        tAcc;   // Time Accuracy Estimate (ns)
        int32_t         nano;   // Nanoseconds of second
        uint16_t        year;
        uint8_t         month;
        uint8_t         day;
        uint8_t         hour;
        uint8_t         min;
        uint8_t         sec;
        uint8_t         valid;  // Validity Flags
};

// Space Vehicle (SV) Information

// Single SV information block

#define SVUSED          (1 << 0) // This SV is used for navigation
#define DIFFCORR        (1 << 1) // Differential correction available
#define ORBITAVAIL      (1 << 2) // Orbit information available
#define ORBITEPH        (1 << 3) // Orbit information is Ephemeris
#define UNHEALTHY       (1 << 4) // SV is unhealthy
#define ORBITALM        (1 << 5) // Orbit information is Almanac Plus
#define ORBITAOP        (1 << 6) // Orbit information is AssistNow Autonomous
#define SMOOTHED        (1 << 7) // Carrier smoothed pseudoranges used

struct UBX_NAV_SVINFO_SV {
        uint8_t         chn;      // Channel number
        uint8_t         svid;     // Satellite ID
        uint8_t         flags;    // Misc SV information
        uint8_t         quality;  // Misc quality indicators
        uint8_t         cno;      // Carrier to Noise Ratio (dbHz)
        int8_t          elev;     // Elevation (integer degrees)
        int16_t         azim;     // Azimuth    (integer degrees)
        int32_t         prRes;    // Pseudo range residual (cm)
};

// SV information message
#define MAX_SVS         32

struct UBX_NAV_SVINFO {
        uint32_t        iTOW;         // GPS Millisecond Time of Week (ms)
        uint8_t         numCh;        // Number of channels
        uint8_t         globalFlags;  //
        uint16_t        reserved2;    // Reserved
        struct UBX_NAV_SVINFO_SV        sv[MAX_SVS]; // Repeated 'numCh' times
};

struct UBX_MON_VER {
        uint8_t     swVersion[30];
        uint8_t     hwVersion[10];
        uint8_t     extra[30];
};

typedef union {
        uint8_t         payload[0];
        struct UBX_NAV_POSLLH   nav_posllh;
        struct UBX_NAV_STATUS   nav_status;
        struct UBX_NAV_DOP              nav_dop;
        struct UBX_NAV_SOL              nav_sol;
        struct UBX_NAV_VELNED   nav_velned;
        struct UBX_NAV_TIMEUTC  nav_timeutc;
        struct UBX_NAV_SVINFO   nav_svinfo;
        struct UBX_MON_VER      mon_ver;
} UBXPayload;

struct UBXHeader {
        uint8_t         class;
        uint8_t         id;
        uint16_t        len;
        uint8_t         ck_a;
        uint8_t         ck_b;
};

struct UBXPacket {
        struct UBXHeader        header;
        UBXPayload      payload;
};

int  parse_ubx_stream(uint8_t, char *, GPSPositionData *, struct GPS_RX_STATS *);

#endif /* UBX_H */