tsip.c

gpsd, a popular GPS daemon.

/* $Id: tsip.c 4661 2008-01-19 22:54:23Z garyemiller $ */
/*
 * Handle the Trimble TSIP packet format
 * by Rob Janssen, PE1CHL.
 */
#include <sys/types.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <math.h>
#include "gpsd_config.h"
#include "gpsd.h"
#include "bits.h"

#define USE_SUPERPACKET	1			/* use Super Packet mode? */

#define SEMI_2_DEG	(180.0 / 2147483647)	/* 2^-31 semicircle to deg */

#ifdef TSIP_ENABLE
#define TSIP_CHANNELS	12

static int tsip_write(int fd, unsigned int id, unsigned char *buf, size_t len)
{
#ifdef ALLOW_RECONFIGURE
    char buf2[BUFSIZ];

    gpsd_report(LOG_IO, "Sent TSIP packet id 0x%02x: %s\n",id,gpsd_hexdump(buf,len));

    /*@ +charint @*/
    buf2[0] = '\x10';
    buf2[1] = (char)id;
    if (write(fd,buf2,2) != 2)
	return -1;

    while (len-- > 0) {
	if (*buf == '\x10')
	    if (write(fd,buf2,1) != 1)
		return -1;

	if (write(fd,buf++,1) != 1)
	    return -1;
    }

    buf2[1] = '\x03';
    /*@ -charint @*/
    if (write(fd,buf2,2) != 2)
	return -1;

    return 0;
#else
    gpsd_report(LOG_IO, "Not sending TSIP packet id 0x%02x: %s\n",id,gpsd_hexdump(buf,len));
    return -1;
#endif /* ALLOW_RECONFIGURE */
}

static void tsip_probe_subtype(struct gps_device_t *session, unsigned int seq)
{
    unsigned char buf[100];

    switch (seq) {
    case 0:
	/* TSIP is ODD parity 1 stopbit, save original values and change it */
	/* XXX this is not always a good idea; not all receivers are 8O1... */
	session->driver.tsip.parity = session->gpsdata.parity;
	session->driver.tsip.stopbits = session->gpsdata.stopbits;
	gpsd_set_speed(session, session->gpsdata.baudrate, 'O', 1);
	break;

    case 1:
	/* Request Software Versions */
	(void)tsip_write(session->gpsdata.gps_fd, 0x1f, NULL, 0);
	/* Request Current Time */
	(void)tsip_write(session->gpsdata.gps_fd, 0x21, NULL, 0);
	/* Request GPS Systems Message */
	(void)tsip_write(session->gpsdata.gps_fd, 0x28, NULL, 0);
	/* Request Current Datum Values */
	putbyte(buf,0,0x15);
	(void)tsip_write(session->gpsdata.gps_fd, 0x8e, buf, 1);
	/* Request Navigation Configuration */
	putbyte(buf,0,0x03);
	(void)tsip_write(session->gpsdata.gps_fd, 0xbb, buf, 1);
	break;
    }
}

#ifdef ALLOW_RECONFIGURE
static void tsip_configurator(struct gps_device_t *session, unsigned int seq)
{
    if (seq == 0) {
	unsigned char buf[100];

	/* I/O Options */
	putbyte(buf,0,0x1e);		/* Position: DP, MSL, LLA */
	putbyte(buf,1,0x02);		/* Velocity: ENU */
	putbyte(buf,2,0x00);		/* Time: GPS */
	putbyte(buf,3,0x08);		/* Aux: dBHz */
	(void)tsip_write(session->gpsdata.gps_fd, 0x35, buf, 4);
    }
}
#endif /* ALLOW_RECONFIGURE */

static void tsip_wrapup(struct gps_device_t *session)
{
    /* restore saved parity and stopbits when leaving TSIP mode */
    gpsd_set_speed(session, 
		   session->gpsdata.baudrate,
		   (unsigned char)session->driver.tsip.parity, 
		   session->driver.tsip.stopbits);
}

static bool tsip_speed_switch(struct gps_device_t *session, unsigned int speed)
{
    unsigned char buf[100];

    putbyte(buf,0,0xff);		/* current port */
    putbyte(buf,1,(round(log((double)speed/300)/M_LN2))+2); /* input baudrate */
    putbyte(buf,2,getub(buf,1));	/* output baudrate */
    putbyte(buf,3,8);			/* character width (8 bits) */
    putbyte(buf,4,1);			/* parity (odd) */
    putbyte(buf,5,0);			/* stop bits (1 stopbit) */
    putbyte(buf,6,0);			/* flow control (none) */
    putbyte(buf,7,0x02);		/* input protocol (TSIP) */
    putbyte(buf,8,0x02);		/* output protocol (TSIP) */
    putbyte(buf,9,0);			/* reserved */
    (void)tsip_write(session->gpsdata.gps_fd, 0xbc, buf, 10);

    return true;	/* it would be nice to error-check this */
}

static gps_mask_t tsip_analyze(struct gps_device_t *session)
{
    int i, j, len, count;
    gps_mask_t mask = 0;
    unsigned int id;
    u_int8_t u1,u2,u3,u4,u5;
    int16_t s1,s2,s3,s4;
    int32_t sl1,sl2,sl3;
    u_int32_t ul1,ul2;
    float f1,f2,f3,f4,f5;
    double d1,d2,d3,d4,d5;
    union int_float i_f;
    union long_double l_d;
    time_t now;
    unsigned char buf[BUFSIZ];
    char buf2[BUFSIZ];

    if (session->packet.type != TSIP_PACKET) {
	gpsd_report(LOG_INF, "tsip_analyze packet type %d\n",session->packet.type);
	return 0;
    }

    /*@ +charint @*/
    if (session->packet.outbuflen < 4 || session->packet.outbuffer[0] != 0x10)
	return 0;

    /* remove DLE stuffing and put data part of message in buf */

    memset(buf, 0, sizeof(buf));
    buf2[len = 0] = '\0';
    for (i = 2; i < (int)session->packet.outbuflen; i++) {
	if (session->packet.outbuffer[i] == 0x10)
	    if (session->packet.outbuffer[++i] == 0x03)
		break;

	(void)snprintf(buf2+strlen(buf2), 
		      sizeof(buf2)-strlen(buf2),
		      "%02x", buf[len++] = session->packet.outbuffer[i]);
    }
    /*@ -charint @*/

    (void)snprintf(session->gpsdata.tag, sizeof(session->gpsdata.tag), 
		   "ID%02x", id = (unsigned)session->packet.outbuffer[1]);

    gpsd_report(LOG_IO, "TSIP packet id 0x%02x length %d: %s\n",id,len,buf2);
    (void)time(&now);

    switch (id) {
    case 0x13:		/* Packet Received */
	u1 = getub(buf,0);
	u2 = getub(buf,1);
	gpsd_report(LOG_WARN, "Received packet of type %02x cannot be parsed\n",u1);
#if USE_SUPERPACKET
	if ((int)u1 == 0x8e && (int)u2 == 0x23) { /* no Compact Super Packet */
	    gpsd_report(LOG_WARN, "No Compact Super Packet, use LFwEI\n");

	    /* Request LFwEI Super Packet */
	    putbyte(buf,0,0x20);
	    putbyte(buf,1,0x01);		/* enabled */
	    (void)tsip_write(session->gpsdata.gps_fd, 0x8e, buf, 2);
	}
#endif /* USE_SUPERPACKET */
	break;
    case 0x41:		/* GPS Time */
	if (len != 10)
	    break;
	session->driver.tsip.last_41 = now;			/* keep timestamp for request */
	f1 = getf(buf,0);			/* gpstime */
	s1 = getsw(buf,4);			/* week */
	f2 = getf(buf,6);			/* leap seconds */
	if (f1 >= 0.0 && f2 > 10.0) {
	    session->driver.tsip.gps_week = s1;
	    session->context->leap_seconds = (int)round(f2);
	    session->context->valid |= LEAP_SECOND_VALID;

	    session->gpsdata.sentence_time = gpstime_to_unix((int)s1, f1) - f2;

#ifdef NTPSHM_ENABLE
	    if (session->context->enable_ntpshm)
		(void)ntpshm_put(session,session->gpsdata.sentence_time+0.075);
#endif
	    mask |= TIME_SET;
	}
	gpsd_report(LOG_INF, "GPS Time %f %d %f\n",f1,s1,f2);
	break;
    case 0x42:		/* Single-Precision Position Fix, XYZ ECEF */
	if (len != 16)
	    break;
	f1 = getf(buf,0);			/* X */
	f2 = getf(buf,4);			/* Y */
	f3 = getf(buf,8);			/* Z */
	f4 = getf(buf,12);			/* time-of-fix */
	gpsd_report(LOG_INF, "GPS Position XYZ %f %f %f %f\n",f1,f2,f3,f4);
	break;
    case 0x43:		/* Velocity Fix, XYZ ECEF */
	if (len != 20)
	    break;
	f1 = getf(buf,0);			/* X velocity */
	f2 = getf(buf,4);			/* Y velocity */
	f3 = getf(buf,8);			/* Z velocity */
	f4 = getf(buf,12);			/* bias rate */
	f5 = getf(buf,16);			/* time-of-fix */
	gpsd_report(LOG_INF, "GPS Velocity XYZ %f %f %f %f %f\n",f1,f2,f3,f4,f5);
	break;
    case 0x45:		/* Software Version Information */
	if (len != 10)
	    break;
	/*@ -formattype @*/
	(void)snprintf(session->subtype, sizeof(session->subtype), 
		       "%d.%d %02d%02d%02d %d.%d %02d%02d%02d",
		       getub(buf,0),getub(buf,1),getub(buf,4),getub(buf,2),getub(buf,3),
		       getub(buf,5),getub(buf,6),getub(buf,9),getub(buf,7),getub(buf,8));
	/*@ +formattype @*/
	gpsd_report(LOG_INF, "Software version: %s\n", session->subtype);
	mask |= DEVICEID_SET;
	break;
    case 0x46:		/* Health of Receiver */
	if (len != 2)
	    break;
	session->driver.tsip.last_46 = now;
	u1 = getub(buf,0);			/* Status code */
	u2 = getub(buf,1);			/* Antenna/Battery */
        if (u1 != (u_int8_t)0) {
            session->gpsdata.status = STATUS_NO_FIX;
	    mask |= STATUS_SET;
        }
	else {
	    if (session->gpsdata.status < STATUS_FIX) {
                session->gpsdata.status = STATUS_FIX;
                mask |= STATUS_SET;
            }
        }
	gpsd_report(LOG_PROG, "Receiver health %02x %02x\n",u1,u2);
	break;
    case 0x47:		/* Signal Levels for all Satellites */
	count = (int)getub(buf,0);		/* satellite count */
	if (len != (5*count + 1))
	    break;
	buf2[0] = '\0';
	for (i = 0; i < count; i++) {
	    u1 = getub(buf,5*i + 1);
	    if ((f1 = getf(buf,5*i + 2)) < 0)
		f1 = 0.0;
	    for (j = 0; j < TSIP_CHANNELS; j++)
		if (session->gpsdata.PRN[j] == (int)u1) {
		    session->gpsdata.ss[j] = (int)round(f1);
		    break;
		}
	    (void)snprintf(buf2+strlen(buf2), sizeof(buf2)-strlen(buf2),
			   " %d=%.1f",(int)u1,f1);
	}
	gpsd_report(LOG_PROG, "Signal Levels (%d):%s\n",count,buf2);
	mask |= SATELLITE_SET;
	break;
    case 0x48:		/* GPS System Message */
	buf[len] = '\0';
	gpsd_report(LOG_PROG, "GPS System Message: %s\n",buf);
	break;
    case 0x4a:		/* Single-Precision Position LLA */
	if (len != 20)
	    break;
	session->gpsdata.fix.latitude  = getf(buf,0) * RAD_2_DEG;
	session->gpsdata.fix.longitude = getf(buf,4) * RAD_2_DEG;
	session->gpsdata.fix.altitude  = getf(buf,8);
	f1 = getf(buf,12);			/* clock bias */
	f2 = getf(buf,16);			/* time-of-fix */
	if (session->driver.tsip.gps_week) {
	    session->gpsdata.fix.time = session->gpsdata.sentence_time =
		gpstime_to_unix((int)session->driver.tsip.gps_week, f2) - session->context->leap_seconds;
	    mask |= TIME_SET;
	}
	gpsd_report(LOG_PROG, "GPS LLA %f %f %f %f\n",
		    session->gpsdata.fix.time,
		    session->gpsdata.fix.latitude,
		    session->gpsdata.fix.longitude,
		    session->gpsdata.fix.altitude);
	mask |= LATLON_SET | ALTITUDE_SET | CYCLE_START_SET;
	break;
    case 0x4b:		/* Machine/Code ID and Additional Status */
	if (len != 3)
	    break;
	u1 = getub(buf,0);			/* Machine ID */
	u2 = getub(buf,1);			/* Status 1 */
	u3 = getub(buf,2);			/* Status 2 */
	gpsd_report(LOG_INF, "Machine ID %02x %02x %02x\n",u1,u2,u3);
#if USE_SUPERPACKET
	if ((u3 & 0x01) != (u_int8_t)0 && !session->driver.tsip.superpkt) {
	    gpsd_report(LOG_PROG, "Switching to Super Packet mode\n");

	    /* set new I/O Options for Super Packet output */
	    putbyte(buf,0,0x2c);		/* Position: SP, MSL */
	    putbyte(buf,1,0x00);		/* Velocity: none (via SP) */
	    putbyte(buf,2,0x00);		/* Time: GPS */
	    putbyte(buf,3,0x08);		/* Aux: dBHz */
	    (void)tsip_write(session->gpsdata.gps_fd, 0x35, buf, 4);
	    session->driver.tsip.superpkt = true;
	}
#endif /* USE_SUPERPACKET */
	break;
    case 0x55:		/* IO Options */
	if (len != 4)
	    break;
	u1 = getub(buf,0);			/* Position */
	u2 = getub(buf,1);			/* Velocity */
	u3 = getub(buf,2);			/* Timing */
	u4 = getub(buf,3);			/* Aux */
	gpsd_report(LOG_INF, "IO Options %02x %02x %02x %02x\n",u1,u2,u3,u4);
#if USE_SUPERPACKET
	if ((u1 & 0x20) != (u_int8_t)0) {	/* Output Super Packets? */
	    /* No LFwEI Super Packet */
	    putbyte(buf,0,0x20);
	    putbyte(buf,1,0x00);		/* disabled */
	    (void)tsip_write(session->gpsdata.gps_fd, 0x8e, buf, 2);

	    /* Request Compact Super Packet */
	    putbyte(buf,0,0x23);
	    putbyte(buf,1,0x01);		/* enabled */
	    (void)tsip_write(session->gpsdata.gps_fd, 0x8e, buf, 2);
	}
#endif /* USE_SUPERPACKET */
	break;
    case 0x56:		/* Velocity Fix, East-North-Up (ENU) */
	if (len != 20)
	    break;
	f1 = getf(buf,0);			/* East velocity */
	f2 = getf(buf,4);			/* North velocity */
	f3 = getf(buf,8);			/* Up velocity */
	f4 = getf(buf,12);			/* clock bias rate */
	f5 = getf(buf,16);			/* time-of-fix */
	session->gpsdata.fix.climb = f3;
	/*@ -evalorder @*/
	session->gpsdata.fix.speed = sqrt(pow(f2,2) + pow(f1,2));
	/*@ +evalorder @*/
	if ((session->gpsdata.fix.track = atan2(f1,f2) * RAD_2_DEG) < 0)
	    session->gpsdata.fix.track += 360.0;
	gpsd_report(LOG_INF, "GPS Velocity ENU %f %f %f %f %f\n",f1,f2,f3,f4,f5);
	mask |= SPEED_SET | TRACK_SET | CLIMB_SET; 
	break;
    case 0x57:		/* Information About Last Computed Fix */
	if (len != 8)
	    break;
	u1 = getub(buf,0);			/* Source of information */
	u2 = getub(buf,1);			/* Mfg. diagnostic */
	f1 = getf(buf,2);			/* gps_time */
	s1 = getsw(buf,6);			/* tsip.gps_week */
	/*@ +charint @*/
	if (getub(buf,0) == 0x01)		/* good current fix? */
	    session->driver.tsip.gps_week = s1;
	/*@ -charint @*/