gpsd/gpsmon/monitor_sirf.c

/*
 * SiRF object for the GPS packet monitor.
 *
 * This file is Copyright 2010 by the GPSD project
 * SPDX-License-Identifier: BSD-2-clause
 *
 */

#include "../include/gpsd_config.h"  /* must be before all includes */

#include <assert.h>
#include <math.h>
#include <stdbool.h>
#include <stdlib.h> /* for labs() */
#include <string.h>
#include <sys/time.h>
#include <time.h>

#include "../include/gpsd.h"
#include "../include/bits.h"
#include "../include/gpsmon.h"
#include "../include/strfuncs.h"

#if defined(SIRF_ENABLE) && defined(BINARY_ENABLE)
extern const struct gps_type_t driver_sirf;

static WINDOW *mid2win, *mid4win, *mid6win, *mid7win, *mid9win, *mid13win;
static WINDOW *mid19win, *mid27win;
static bool dispmode = false, subframe_enabled = false, ppstime_enabled = false;
static int leapseconds;

static char *verbpat[] = {
    "#Time:",
    "@R Time:",
    "CSTD: New almanac for",
    "NOTICE: DOP Q Boost",
    "RTC not set",
    "numOfSVs = 0",
    "rtcaj tow ",
    NULL
};


static char *dgpsvec[] = {
    "None",
    "SBAS",
    "Serial",
    "Beacon",
    "Software",
};

/* check range of an unsigned quantity */
#define CHECK_RANGE(vec, i) ((i) < sizeof(vec)/sizeof(vec[0]))

/*****************************************************************************
 *
 * SiRF packet-decoding routines
 *
 *****************************************************************************/

#define display (void)mvwprintw

#define SIRF_CHANNELS   12      /* max channels allowed in SiRF format */

static bool sirf_initialize(void)
{
    unsigned int i;

    mid2win = subwin(devicewin, 6, 80, 1, 0);
    mid4win = subwin(devicewin, SIRF_CHANNELS + 3, 30, 7, 0);
    mid6win = subwin(devicewin, 3, 50, 7, 30);
    mid7win = subwin(devicewin, 4, 50, 13, 30);
    mid9win = subwin(devicewin, 3, 50, 10, 30);
    mid13win = subwin(devicewin, 3, 50, 17, 30);
    mid19win = newwin(16, 50, 7, 30);
    mid27win = subwin(devicewin, 3, 50, 20, 30);
    if (mid2win == NULL || mid4win == NULL || mid6win == NULL
        || mid9win == NULL || mid13win == NULL || mid19win == NULL
        || mid27win == NULL)
        return false;

    (void)syncok(mid2win, true);
    (void)syncok(mid4win, true);
    (void)syncok(mid6win, true);
    (void)syncok(mid7win, true);
    (void)syncok(mid9win, true);
    (void)syncok(mid13win, true);
    (void)syncok(mid27win, true);

    (void)wborder(mid2win, 0, 0, 0, 0, 0, 0, 0, 0),
        (void)wattrset(mid2win, A_BOLD);
    (void)wmove(mid2win, 0, 1);
    display(mid2win, 0, 12, " X ");
    display(mid2win, 0, 21, " Y ");
    display(mid2win, 0, 30, " Z ");
    display(mid2win, 0, 43, " North ");
    display(mid2win, 0, 54, " East ");
    display(mid2win, 0, 65, " Alt ");

    (void)wmove(mid2win, 1, 1);
    (void)wprintw(mid2win,
                  "Pos:                            m                                    m");
    (void)wmove(mid2win, 2, 1);
    (void)wprintw(mid2win,
                  "Vel:                            m/s"
                  "                                  climb m/s");
    (void)wmove(mid2win, 3, 1);
    (void)wprintw(mid2win,
                  "Time:                          Leap:        Heading:"
                  "                 speed m/s");
    (void)wmove(mid2win, 4, 1);
    (void)wprintw(mid2win,
                  "Fix:                                                 HDOP:"
                  "      M1:     M2:   ");
    display(mid2win, 5, 24, " Packet type 2 (0x02) ");
    (void)wattrset(mid2win, A_NORMAL);

    (void)wborder(mid4win, 0, 0, 0, 0, 0, 0, 0, 0),
        (void)wattrset(mid4win, A_BOLD);
    display(mid4win, 1, 1, "Ch PRN  Az El Stat  C/N ? SF");
    for (i = 0; i < SIRF_CHANNELS; i++) {
        display(mid4win, (int)(i + 2), 1, "%2d", i);
    }
    display(mid4win, 0, 1, " Measured Tracker ");
    display(mid4win, 14, 4, " Packet Type 4 (0x04) ");
    (void)wattrset(mid4win, A_NORMAL);

    (void)wborder(mid19win, 0, 0, 0, 0, 0, 0, 0, 0),
        (void)wattrset(mid19win, A_BOLD);
    display(mid19win, 1, 1, "Alt. hold mode:");
    display(mid19win, 2, 1, "Alt. hold source:");
    display(mid19win, 3, 1, "Alt. source input:");
    display(mid19win, 4, 1, "Degraded timeout:");
    display(mid19win, 5, 1, "DR timeout:");
    display(mid19win, 6, 1, "Track smooth mode:");
    display(mid19win, 7, 1, "Static Navigation:");
    display(mid19win, 8, 1, "3SV Least Squares:");
    display(mid19win, 9, 1, "DOP Mask mode:");
    display(mid19win, 10, 1, "Nav. Elev. mask:");
    display(mid19win, 11, 1, "Nav. Power mask:");
    display(mid19win, 12, 1, "DGPS Source:");
    display(mid19win, 13, 1, "DGPS Mode:");
    display(mid19win, 14, 1, "DGPS Timeout:");
    display(mid19win, 1, 26, "LP Push-to-Fix:");
    display(mid19win, 2, 26, "LP On Time:");
    display(mid19win, 3, 26, "LP Interval:");
    display(mid19win, 4, 26, "U. Tasks Enab.:");
    display(mid19win, 5, 26, "U. Task Inter.:");
    display(mid19win, 6, 26, "LP Pwr Cyc En:");
    display(mid19win, 7, 26, "LP Max Acq Srch:");
    display(mid19win, 8, 26, "LP Max Off Time:");
    display(mid19win, 9, 26, "APM enabled:");
    display(mid19win, 10, 26, "# of Fixes:");
    display(mid19win, 11, 26, "Time btw Fixes:");
    display(mid19win, 12, 26, "H/V Error Max:");
    display(mid19win, 13, 26, "Rsp Time Max:");
    display(mid19win, 14, 26, "Time/Accu:");

    display(mid19win, 15, 8, " Packet type 19 (0x13) ");
    (void)wattrset(mid19win, A_NORMAL);

    (void)wborder(mid6win, 0, 0, 0, 0, 0, 0, 0, 0),
        (void)wattrset(mid6win, A_BOLD);
    display(mid6win, 0, 1, " Firmware Version ");
    display(mid6win, 2, 8, " Packet Type 6 (0x06) ");
    (void)wattrset(mid6win, A_NORMAL);

    (void)wborder(mid7win, 0, 0, 0, 0, 0, 0, 0, 0),
        (void)wattrset(mid7win, A_BOLD);
    display(mid7win, 0, 1, " Clock Status ");
    display(mid7win, 1, 1, "SVs: ");
    display(mid7win, 1, 9, "Drift: ");
    display(mid7win, 1, 23, "Bias: ");
    display(mid7win, 2, 1, "GPS Time: ");
    display(mid7win, 2, 23, "PPS: ");
    (void)syncok(mid7win, true);
    (void)mvwaddstr(mid7win, 2, 40, "N/A");
    display(mid7win, 3, 8, " Packet type 7 (0x07) ");
    (void)wattrset(mid7win, A_NORMAL);

    (void)wborder(mid9win, 0, 0, 0, 0, 0, 0, 0, 0),
        (void)wattrset(mid9win, A_BOLD);
    display(mid9win, 0, 1, " CPU Throughput ");
    display(mid9win, 1, 1, "Max: ");
    display(mid9win, 1, 13, "Lat: ");
    display(mid9win, 1, 25, "Time: ");
    display(mid9win, 1, 39, "MS: ");
    display(mid9win, 2, 8, " Packet type 9 (0x09) ");
    (void)wattrset(mid9win, A_NORMAL);

    (void)wborder(mid13win, 0, 0, 0, 0, 0, 0, 0, 0),
        (void)wattrset(mid13win, A_BOLD);
    display(mid13win, 0, 1, " Visible List ");
    display(mid13win, 2, 8, " Packet type 13 (0x0D) ");
    (void)wattrset(mid13win, A_NORMAL);

    (void)wborder(mid27win, 0, 0, 0, 0, 0, 0, 0, 0),
        (void)wattrset(mid27win, A_BOLD);
    display(mid27win, 0, 1, " DGPS Status ");
    display(mid27win, 2, 8, " Packet type 27 (0x1B) ");
    (void)wattrset(mid27win, A_NORMAL);

    /* probe for version */
    (void)monitor_control_send((unsigned char *)"\x84\x00", 2);

    /* initialize the GPS context's time fields */
    gpsd_time_init(session.context, time(NULL));

    return true;
}

static void decode_ecef(double x, double y, double z,
                        double vx, double vy, double vz)
{
    const double a = WGS84A;
    const double b = WGS84B;
    const double e2 = (a * a - b * b) / (a * a);
    const double e_2 = (a * a - b * b) / (b * b);
    double lambda, p, theta, phi, n, h, vnorth, veast, vup, speed, heading;

    lambda = atan2(y, x);
    p = sqrt(pow(x, 2) + pow(y, 2));
    theta = atan2(z * a, p * b);
    phi =
        atan2(z + e_2 * b * pow(sin(theta), 3),
              p - e2 * a * pow(cos(theta), 3));
    n = a / sqrt(1.0 - e2 * pow(sin(phi), 2));
    h = p / cos(phi) - n;
    h -= wgs84_separation((double)(RAD_2_DEG * phi),
                          (double)(RAD_2_DEG * lambda));
    vnorth =
        -vx * sin(phi) * cos(lambda) - vy * sin(phi) * sin(lambda) +
        vz * cos(phi);
    veast = -vx * sin(lambda) + vy * cos(lambda);
    vup =
        vx * cos(phi) * cos(lambda) + vy * cos(phi) * sin(lambda) +
        vz * sin(phi);
    speed = sqrt(pow(vnorth, 2) + pow(veast, 2));
    heading = atan2(veast, vnorth);
    if (heading < 0)
        heading += 2 * GPS_PI;

    /* North and East position fields */
    (void)wattrset(mid2win, A_UNDERLINE);
    (void)wmove(mid2win, 1, 40);
    (void)wprintw(mid2win, "%9.5f %9.5f %9d",
                        (double)(RAD_2_DEG * phi),
                        (double)(RAD_2_DEG * lambda),
                        (int)h);
    (void)mvwaddch(mid2win, 1, 49, ACS_DEGREE);
    (void)mvwaddch(mid2win, 1, 59, ACS_DEGREE);

    /* North and East velocity fields */
    (void)wmove(mid2win, 2, 40);
    (void)wprintw(mid2win, "%9.1f %9.1f %9.1f", vnorth, veast, vup);

    /* heading and speed fields */
    (void)wmove(mid2win, 3, 54);
    (void)wprintw(mid2win, "%5.1f %9.1f", (double)(RAD_2_DEG * heading), speed);
    (void)mvwaddch(mid2win, 3, 59, ACS_DEGREE);
    (void)wattrset(mid2win, A_NORMAL);
}

static void sirf_update(void)
{
    int i, j, ch, sv;
    unsigned u, x;
    unsigned char *buf;
    size_t len;
    uint8_t dgps;
    char tbuf[JSON_DATE_MAX+1];

    buf = session.lexer.outbuffer + 4;
    len = session.lexer.outbuflen - 8;
    switch (buf[0]) {
    case 0x02:                  /* Measured Navigation Data */
        (void)wmove(mid2win, 1, 6);     /* ECEF position */
        (void)wprintw(mid2win, "%8d %8d %8d", getbes32(buf, 1),
                      getbes32(buf, 5), getbes32(buf, 9));
        (void)wmove(mid2win, 2, 6);     /* ECEF velocity */
        (void)wprintw(mid2win, "%8.1f %8.1f %8.1f",
                      (double)getbes16(buf, 13) / 8, (double)getbes16(buf,
                                                                    15) / 8,
                      (double)getbes16(buf, 17) / 8);
        decode_ecef((double)getbes32(buf, 1), (double)getbes32(buf, 5),
                    (double)getbes32(buf, 9), (double)getbes16(buf, 13) / 8,
                    (double)getbes16(buf, 15) / 8, (double)getbes16(buf,
                                                                  17) / 8);
        /* line 3 */
        (void)wmove(mid2win, 3, 7);
        if (0 < session.gpsdata.fix.time.tv_sec) {
            (void)wprintw(mid2win, "%-24s",
                          timespec_to_iso8601(session.gpsdata.fix.time, tbuf,
                          sizeof(tbuf)));
        }
        (void)wmove(mid2win, 3, 38);
        (void)wattrset(mid2win, A_UNDERLINE);
        if (ppstime_enabled)
           (void)wprintw(mid2win, "%02d", leapseconds);
        else
           (void)wprintw(mid2win, "??");
        (void)wattrset(mid2win, A_NORMAL);
        /* line 4 */
        /* HDOP */
        (void)wmove(mid2win, 4, 59);
        (void)wprintw(mid2win, "%4.1f", (double)getub(buf, 20) / 5);
        /* Mode 1 */
        (void)wmove(mid2win, 4, 69);
        (void)wprintw(mid2win, "%02x", getub(buf, 19));
        /* Mode 2 */
        (void)wmove(mid2win, 4, 77);
        (void)wprintw(mid2win, "%02x", getub(buf, 21));
        /* SVs in fix */
        (void)wmove(mid2win, 4, 6);
        (void)wprintw(mid2win, "%2u =                                     ",
                      getub(buf, 28));
        /* SV list */
        (void)wmove(mid2win, 4, 10);
        x = getub(buf, 28);
        if (19 < x) {
            x = 19;      // SiRF Star V max is 19
        }
        for (u = 0; u < x; u++)
           (void)wprintw(mid2win, " %2u", getub(buf, 29 + u));
        monitor_log("MND 0x02=");
        break;

    case 0x04:                  /* Measured Tracking Data */
        ch = (int)getub(buf, 7);
        for (i = 0; i < ch; i++) {
            int az, el, state, off;
            double cn;

            off = 8 + 15 * i;
            (void)wmove(mid4win, i + 2, 3);

            sv = (int)getub(buf, off);
            az = (int)getub(buf, off + 1) * 3 / 2;
            el = (int)getub(buf, off + 2) / 2;
            state = (int)getbeu16(buf, off + 3);
            cn = 0;
            for (j = 0; j < 10; j++)
                cn += (int)getub(buf, off + 5 + j);
            cn /= 10;

            (void)wprintw(mid4win, " %3d %3d %2d %04x %4.1f %c",
                           sv, az, el, state, cn, state == 0xbf ? 'T' : ' ');
        }
        monitor_log("MTD 0x04=");
        break;

#ifdef __UNUSED__
    case 0x05:                  /* raw track data */
        for (off = 1; off < len; off += 51) {
            ch = getbeu32(buf, off);
            (void)wmove(mid4win, ch + 2, 19);
            cn = 0;

            for (j = 0; j < 10; j++)
                cn += getub(buf, off + 34 + j);

            printw("%5.1f", (double)cn / 10);

            printw("%9d%3d%5d", getbeu32(buf, off + 8),
                   (int)getbeu16(buf, off + 12), (int)getbeu16(buf, off + 14));
            printw("%8.5f %10.5f", (double)getbeu32(buf, off + 16) / 65536,
                   (double)getbeu32(buf, off + 20) / 1024);
        }
        monitor_log("RTD 0x05=");
        break;
#endif /* __UNUSED */

    case 0x06:                  /* firmware version */
        display(mid6win, 1, 1, "%s", buf + 1);
        monitor_log("FV  0x06=");
        break;

    case 0x07:                  /* Response - Clock Status Data */
        display(mid7win, 1, 5, "%2d", getub(buf, 7));   /* SVs */
        /* Clock ppstimes */
        display(mid7win, 1, 16, "%lu", (unsigned long)getbeu32(buf, 8));
        display(mid7win, 1, 29, "%lu", (unsigned long)getbeu32(buf, 12));
        /* Clock Bias */
        display(mid7win, 2, 11, "%lu", (unsigned long)getbeu32(buf, 16));
        /* Estimated Time */
        monitor_log("CSD 0x07=");
        break;

    case 0x08:                  /* 50 BPS data */
        ch = (int)getub(buf, 1);
        sv = (int)getub(buf, 2);
        display(mid4win, ch + 2, 27, "%2d", sv);
        subframe_enabled = true;
        monitor_log("50B 0x08=");
        break;

    case 0x09:                  /* Throughput */
        /*SegStatMax */
        display(mid9win, 1, 6, "%.3f", (double)getbeu16(buf, 1) / 186);
        /*SegStatLat */
        display(mid9win, 1, 18, "%.3f", (double)getbeu16(buf, 3) / 186);
        /*SegStatTime */
        display(mid9win, 1, 31, "%.3f", (double)getbeu16(buf, 5) / 186);
        /* Last Millisecond */
        display(mid9win, 1, 42, "%3d", (int)getbeu16(buf, 7));
        monitor_log("THR 0x09=");
        break;

    case 0x0b:                  /* Command Acknowledgement */
        monitor_log("ACK 0x0b=");
        break;

    case 0x0c:                  /* Command NAcknowledgement */
        monitor_log("NAK 0x0c=");
        break;

    case 0x0d:                  /* Visible List */
        display(mid13win, 1, 1, "%02d =                                            ",
                                 getub(buf, 1));
        (void)wmove(mid13win, 1, 5);
        for (i = 0; i < (int)getub(buf, 1); i++)
            (void)wprintw(mid13win, " %d", getub(buf, 2 + 5 * i));
        monitor_log("VL  0x0d=");
        break;

    case 0x13:
#define YESNO(n)        (((int)getub(buf, n) != 0)?'Y':'N')
        display(mid19win, 1, 20, "%d", getub(buf, 5));  /* Alt. hold mode */
        display(mid19win, 2, 20, "%d", getub(buf, 6));  /* Alt. hold source */
        /* Alt. source input */
        display(mid19win, 3, 20, "%dm", (int)getbeu16(buf, 7));
        if (getub(buf, 9) != (uint8_t) '\0') {
            /* Degraded timeout */
            display(mid19win, 4, 20, "%dsec", getub(buf, 10));
        } else {
            display(mid19win, 4, 20, "N/A   ");
        }
        display(mid19win, 5, 20, "%dsec", getub(buf, 11));      /* DR timeout */
        display(mid19win, 6, 20, "%c", YESNO(12));      /* Track smooth mode */
        display(mid19win, 7, 20, "%c", YESNO(13));      /* Static Nav. */
        display(mid19win, 8, 20, "0x%x", getub(buf, 14)); // 3SV Least Squares
        display(mid19win, 9, 20, "0x%x", getub(buf, 19)); /* DOP Mask mode */
        /* Nav. Elev. mask */
        display(mid19win, 10, 20, "0x%x", (int)getbeu16(buf, 20));
        /* Nav. Power mask */
        display(mid19win, 11, 20, "0x%x", getub(buf, 22));
        display(mid19win, 12, 20, "0x%x", getub(buf, 27));    /* DGPS Source */
        display(mid19win, 13, 20, "0x%x", getub(buf, 28));      /* DGPS Mode */
        display(mid19win, 14, 20, "%dsec", getub(buf, 29));     /* DGPS Timeout */
        display(mid19win, 1, 42, "%c", YESNO(34));      /* LP Push-to-Fix */
        display(mid19win, 2, 42, "%dms", getbeu32(buf, 35));   /* LP On Time */
        display(mid19win, 3, 42, "%d", getbeu32(buf, 39));     /* LP Interval */
        display(mid19win, 4, 42, "%c", YESNO(43));      /* User Tasks enabled */
        /* User Task Interval */
        display(mid19win, 5, 42, "%d", getbeu32(buf, 44));
        display(mid19win, 6, 42, "%c", YESNO(48));  // LP Power Cycling Enabled
        /* LP Max Acq Search Time */
        display(mid19win, 7, 42, "%d", getbeu32(buf, 49));
        /* LP Max Off Time */
        display(mid19win, 8, 42, "%d", getbeu32(buf, 53));
        display(mid19win, 9, 42, "%c", YESNO(57));      /* APM Enabled */
        /* # of fixes */
        display(mid19win, 10, 42, "%d", (int)getbeu16(buf, 58));
        /* Time Between fixes */
        display(mid19win, 11, 42, "%d", (int)getbeu16(buf, 60));
        display(mid19win, 12, 42, "%d", getub(buf, 62));   /* H/V Error Max */
        display(mid19win, 13, 42, "%d", getub(buf, 63));   // Response Time Max
        /* Time/Accu & Duty Cycle Priority */
        display(mid19win, 14, 42, "%d", getub(buf, 64));
#undef YESNO
        monitor_log("NP  0x13=");
        break;

    case 0x1b:
        /******************************************************************
         Not actually documented in any published materials before the
         1.6 version of the SiRF binary protocol manual.
         Here is what Chris Kuethe got from the SiRF folks,
         (plus some corrections from the GpsPaSsion forums):

        Start of message
        ----------------
        Message ID          1 byte    27
        Correction Source   1 byte    0=None, 1=SBAS, 2=Serial, 3=Beacon,
        4=Software

        total:              2 bytes

        Middle part of message varies if using beacon or other:
        -------------------------------------------------------
        If Beacon:
        Receiver Freq Hz    4 bytes
        Bit rate BPS        1 byte
        Status bit map      1 byte    01=Signal Valid,
                                      02=Auto frequency detect
                                      04=Auto bit rate detect
        Signal Magnitude    4 bytes   Note: in internal units
        Signal Strength dB  2 bytes   derived from Signal Magnitude
        SNR  dB             2 bytes

        total:             14 bytes

        If Not Beacon:
        Correction Age[12]  1 byte x 12  Age in seconds in same order as follows
        Reserved            2 bytes

        total:             14 bytes

        End of Message
        --------------
        Repeated 12 times (pad with 0 if less than 12 SV corrections):
        SVID                1 byte
        Correction (cm)     2 bytes (signed short)

        total               3 x 12 = 36 bytes
        ******************************************************************/
        dgps = getub(buf, 1);
        display(mid27win, 1, 1, "%8s =                                      ",
                (CHECK_RANGE(dgpsvec, dgps) ? dgpsvec[dgps] : "???"));
        (void)wmove(mid27win, 1, 11);
        for (ch = 0; ch < SIRF_CHANNELS; ch++)
            if (getub(buf, 16 + 3 * ch) != '\0')
                (void)wprintw(mid27win, " %d", getub(buf, 16 + 3 * ch));
        monitor_log("DST 0x1b=");
        break;

    case 0x1c:                  /* NL Measurement Data */
    case 0x1d:                  /* NL DGPS Data */
    case 0x1e:                  /* NL SV State Data */
    case 0x1f:                  /* NL Initialized Data */
        subframe_enabled = true;
        monitor_log("NL  0x%02x=", buf[0]);
        break;

    case 0x29:                  /* Geodetic Navigation Data */
        monitor_log("GND 0x29=");
        break;

    case 0x32:                  /* SBAS Parameters */
        monitor_log("SBP 0x32=");
        break;

    case 0x34:                  /* PPS Time */
        ppstime_enabled = true;
        leapseconds = (int)getbeu16(buf, 8);
        monitor_log("PPS 0x34=");
        break;

    case 0xff:                  /* Development Data */
        while (len > 0 && buf[len - 1] == '\n')
            len--;
        while (len > 0 && buf[len - 1] == ' ')
            len--;
        buf[len] = '\0';
        j = 1;
        for (i = 0; verbpat[i] != NULL; i++)
            if (str_starts_with((char *)(buf + 1), verbpat[i])) {
                j = 0;
                break;
            }
        if (j != 0)
            monitor_log("%s\n", buf + 1);
        monitor_log("DD  0xff=");
        break;

    default:
        monitor_log("UNK 0x%02x=", buf[0]);
        break;
    }

    /* elicit navigation parameters */
    if (dispmode && (time(NULL) % 10 == 0)) {
        (void)monitor_control_send((unsigned char *)"\x98\x00", 2);
    }

    /* clear the 50bps data field every 6 seconds */
    if (subframe_enabled && (time(NULL) % 6 == 0)) {
        for (ch = 0; ch < SIRF_CHANNELS; ch++)
           display(mid4win, ch + 2, 27, "  ");
    }

    if (dispmode) {
        (void)touchwin(mid19win);
        (void)wnoutrefresh(mid19win);
    }

    pps_update(mid7win, 2, 32);
}

static int sirf_command(char line[])
{
    unsigned char buf[BUFSIZ];
    int v;

    switch (line[0]) {
    case 'A':                   /* toggle 50bps subframe data */
        (void)memset(buf, '\0', sizeof(buf));
        putbyte(buf, 0, 0x80);
        putbyte(buf, 23, 0x0c);
        putbyte(buf, 24, subframe_enabled ? 0x00 : 0x10);
        (void)monitor_control_send(buf, 25);
        /*
         * The subframe_enabled off because we're counting on receipt of
         * a subframe packet to turn it on if the command succeeds.
         */
        subframe_enabled = false;
        return COMMAND_MATCH;

    case 'M':                   /* static navigation */
        putbyte(buf, 0, 0x8f);  /* id */
        putbyte(buf, 1, atoi(line + 1));
        (void)monitor_control_send(buf, 2);
        return COMMAND_MATCH;

    case 'D':                   /* MID 4 rate change (undocumented) */
        v = atoi(line + 1);
        if (v > 30)
            return COMMAND_MATCH;
        putbyte(buf, 0, 0xa6);
        putbyte(buf, 1, 0);
        putbyte(buf, 2, 4);     /* satellite picture */
        putbyte(buf, 3, v);
        putbyte(buf, 4, 0);
        putbyte(buf, 5, 0);
        putbyte(buf, 6, 0);
        putbyte(buf, 7, 0);
        (void)monitor_control_send(buf, 8);
        return COMMAND_MATCH;

    case 'P':                   /* poll navigation params */
        dispmode = !dispmode;
        if (dispmode) {
            (void)syncok(mid6win, false);
            (void)syncok(mid7win, false);
            (void)syncok(mid9win, false);
            (void)syncok(mid13win, false);
            (void)syncok(mid27win, false);
        } else {
            (void)syncok(mid6win, true);
            (void)wsyncup(mid6win);
            (void)syncok(mid7win, true);
            (void)wsyncup(mid7win);
            (void)syncok(mid9win, true);
            (void)wsyncup(mid9win);
            (void)syncok(mid13win, true);
            (void)wsyncup(mid13win);
            (void)syncok(mid27win, true);
            (void)wsyncup(mid27win);
        }
        return COMMAND_MATCH;
    }

    return COMMAND_UNKNOWN;     /* no match */
}

static void sirf_wrap(void)
{
    (void)delwin(mid2win);
    (void)delwin(mid4win);
    (void)delwin(mid6win);
    (void)delwin(mid7win);
    (void)delwin(mid9win);
    (void)delwin(mid13win);
    (void)delwin(mid19win);
    (void)delwin(mid27win);
}

const struct monitor_object_t sirf_mmt = {
    .initialize = sirf_initialize,
    .update = sirf_update,
    .command = sirf_command,
    .wrap = sirf_wrap,
    .min_y = 22,.min_x = 80,
    .driver = &driver_sirf,
};
#endif /* defined(SIRF_ENABLE) && defined(BINARY_ENABLE) */

/* sirfmon.c ends here */
// vim: set expandtab shiftwidth=4