Add support for the SkyTraq GPS unit
[fw/altos] / src / ao_gps_sirf.c
diff --git a/src/ao_gps_sirf.c b/src/ao_gps_sirf.c
new file mode 100644 (file)
index 0000000..2b3a517
--- /dev/null
@@ -0,0 +1,457 @@
+/*
+ * Copyright © 2009 Keith Packard <keithp@keithp.com>
+ *
+ * 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; version 2 of the License.
+ *
+ * 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, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#ifndef AO_GPS_TEST
+#include "ao.h"
+#endif
+
+__xdata uint8_t ao_gps_mutex;
+__xdata struct ao_gps_data     ao_gps_data;
+__xdata struct ao_gps_tracking_data    ao_gps_tracking_data;
+
+static const char ao_gps_set_nmea[] = "\r\n$PSRF100,0,57600,8,1,0*37\r\n";
+
+const char ao_gps_config[] = {
+
+       0xa0, 0xa2, 0x00, 0x0e, /* length: 14 bytes */
+       136,                    /* mode control */
+       0, 0,                   /* reserved */
+       0,                      /* degraded mode (allow 1-SV navigation) */
+       0, 0,                   /* reserved */
+       0, 0,                   /* user specified altitude */
+       2,                      /* alt hold mode (disabled, require 3d fixes) */
+       0,                      /* alt hold source (use last computed altitude) */
+       0,                      /* reserved */
+       10,                     /* Degraded time out (10 sec) */
+       10,                     /* Dead Reckoning time out (10 sec) */
+       0,                      /* Track smoothing (disabled) */
+       0x00, 0x8e, 0xb0, 0xb3,
+
+       0xa0, 0xa2, 0x00, 0x08, /* length: 8 bytes */
+       166,                    /* Set message rate */
+       2,                      /* enable/disable all messages */
+       0,                      /* message id (ignored) */
+       0,                      /* update rate (0 = disable) */
+       0, 0, 0, 0,             /* reserved */
+       0x00, 0xa8, 0xb0, 0xb3,
+
+       0xa0, 0xa2, 0x00, 0x02, /* length: 2 bytes */
+       143,                    /* static navigation */
+       0,                      /* disable */
+       0x00, 0x8f, 0xb0, 0xb3,
+};
+
+#define NAV_TYPE_GPS_FIX_TYPE_MASK                     (7 << 0)
+#define NAV_TYPE_NO_FIX                                        (0 << 0)
+#define NAV_TYPE_SV_KF                                 (1 << 0)
+#define NAV_TYPE_2_SV_KF                               (2 << 0)
+#define NAV_TYPE_3_SV_KF                               (3 << 0)
+#define NAV_TYPE_4_SV_KF                               (4 << 0)
+#define NAV_TYPE_2D_LEAST_SQUARES                      (5 << 0)
+#define NAV_TYPE_3D_LEAST_SQUARES                      (6 << 0)
+#define NAV_TYPE_DR                                    (7 << 0)
+#define NAV_TYPE_TRICKLE_POWER                         (1 << 3)
+#define NAV_TYPE_ALTITUDE_HOLD_MASK                    (3 << 4)
+#define NAV_TYPE_ALTITUDE_HOLD_NONE                    (0 << 4)
+#define NAV_TYPE_ALTITUDE_HOLD_KF                      (1 << 4)
+#define NAV_TYPE_ALTITUDE_HOLD_USER                    (2 << 4)
+#define NAV_TYPE_ALTITUDE_HOLD_ALWAYS                  (3 << 4)
+#define NAV_TYPE_DOP_LIMIT_EXCEEDED                    (1 << 6)
+#define NAV_TYPE_DGPS_APPLIED                          (1 << 7)
+#define NAV_TYPE_SENSOR_DR                             (1 << 8)
+#define NAV_TYPE_OVERDETERMINED                                (1 << 9)
+#define NAV_TYPE_DR_TIMEOUT_EXCEEDED                   (1 << 10)
+#define NAV_TYPE_FIX_MI_EDIT                           (1 << 11)
+#define NAV_TYPE_INVALID_VELOCITY                      (1 << 12)
+#define NAV_TYPE_ALTITUDE_HOLD_DISABLED                        (1 << 13)
+#define NAV_TYPE_DR_ERROR_STATUS_MASK                  (3 << 14)
+#define NAV_TYPE_DR_ERROR_STATUS_GPS_ONLY              (0 << 14)
+#define NAV_TYPE_DR_ERROR_STATUS_DR_FROM_GPS           (1 << 14)
+#define NAV_TYPE_DR_ERROR_STATUS_DR_SENSOR_ERROR       (2 << 14)
+#define NAV_TYPE_DR_ERROR_STATUS_DR_IN_TEST            (3 << 14)
+
+struct sirf_geodetic_nav_data {
+       uint16_t        nav_type;
+       uint16_t        utc_year;
+       uint8_t         utc_month;
+       uint8_t         utc_day;
+       uint8_t         utc_hour;
+       uint8_t         utc_minute;
+       uint16_t        utc_second;
+       int32_t         lat;
+       int32_t         lon;
+       int32_t         alt_msl;
+       uint16_t        ground_speed;
+       uint16_t        course;
+       int16_t         climb_rate;
+       uint32_t        h_error;
+       uint32_t        v_error;
+       uint8_t         num_sv;
+       uint8_t         hdop;
+};
+
+static __xdata struct sirf_geodetic_nav_data   ao_sirf_data;
+
+struct sirf_measured_sat_data {
+       uint8_t         svid;
+       uint16_t        state;
+       uint8_t         c_n_1;
+};
+
+struct sirf_measured_tracker_data {
+       int16_t                         gps_week;
+       uint32_t                        gps_tow;
+       uint8_t                         channels;
+       struct sirf_measured_sat_data   sats[12];
+};
+
+static __xdata struct sirf_measured_tracker_data       ao_sirf_tracker_data;
+
+static __pdata uint16_t ao_sirf_cksum;
+static __pdata uint16_t ao_sirf_len;
+
+#define ao_sirf_byte() ((uint8_t) ao_serial_getchar())
+
+static uint8_t data_byte(void)
+{
+       uint8_t c = ao_sirf_byte();
+       --ao_sirf_len;
+       ao_sirf_cksum += c;
+       return c;
+}
+
+static char __xdata *sirf_target;
+
+static void sirf_u16(uint8_t offset)
+{
+       uint16_t __xdata *ptr = (uint16_t __xdata *) (sirf_target + offset);
+       uint16_t val;
+
+       val = data_byte() << 8;
+       val |= data_byte ();
+       *ptr = val;
+}
+
+static void sirf_u8(uint8_t offset)
+{
+       uint8_t __xdata *ptr = (uint8_t __xdata *) (sirf_target + offset);
+       uint8_t val;
+
+       val = data_byte ();
+       *ptr = val;
+}
+
+static void sirf_u32(uint8_t offset) __reentrant
+{
+       uint32_t __xdata *ptr = (uint32_t __xdata *) (sirf_target + offset);
+       uint32_t val;
+
+       val = ((uint32_t) data_byte ()) << 24;
+       val |= ((uint32_t) data_byte ()) << 16;
+       val |= ((uint32_t) data_byte ()) << 8;
+       val |= ((uint32_t) data_byte ());
+       *ptr = val;
+}
+
+static void sirf_discard(uint8_t len)
+{
+       while (len--)
+               data_byte();
+}
+
+#define SIRF_END       0
+#define SIRF_DISCARD   1
+#define SIRF_U8                2
+#define SIRF_U16       3
+#define SIRF_U32       4
+#define SIRF_U8X10     5
+
+struct sirf_packet_parse {
+       uint8_t type;
+       uint8_t offset;
+};
+
+static void
+ao_sirf_parse(void __xdata *target, const struct sirf_packet_parse *parse) __reentrant
+{
+       uint8_t i, offset, j;
+
+       sirf_target = target;
+       for (i = 0; ; i++) {
+               offset = parse[i].offset;
+               switch (parse[i].type) {
+               case SIRF_END:
+                       return;
+               case SIRF_DISCARD:
+                       sirf_discard(offset);
+                       break;
+               case SIRF_U8:
+                       sirf_u8(offset);
+                       break;
+               case SIRF_U16:
+                       sirf_u16(offset);
+                       break;
+               case SIRF_U32:
+                       sirf_u32(offset);
+                       break;
+               case SIRF_U8X10:
+                       for (j = 10; j--;)
+                               sirf_u8(offset++);
+                       break;
+               }
+       }
+}
+
+static const struct sirf_packet_parse geodetic_nav_data_packet[] = {
+       { SIRF_DISCARD, 2 },                                                    /* 1 nav valid */
+       { SIRF_U16, offsetof(struct sirf_geodetic_nav_data, nav_type) },        /* 3 */
+       { SIRF_DISCARD, 6 },                                                    /* 5 week number, time of week */
+       { SIRF_U16, offsetof(struct sirf_geodetic_nav_data, utc_year) },        /* 11 */
+       { SIRF_U8, offsetof(struct sirf_geodetic_nav_data, utc_month) },        /* 13 */
+       { SIRF_U8, offsetof(struct sirf_geodetic_nav_data, utc_day) },          /* 14 */
+       { SIRF_U8, offsetof(struct sirf_geodetic_nav_data, utc_hour) },         /* 15 */
+       { SIRF_U8, offsetof(struct sirf_geodetic_nav_data, utc_minute) },       /* 16 */
+       { SIRF_U16, offsetof(struct sirf_geodetic_nav_data, utc_second) },      /* 17 */
+       { SIRF_DISCARD, 4 },    /* satellite id list */                         /* 19 */
+       { SIRF_U32, offsetof(struct sirf_geodetic_nav_data, lat) },             /* 23 */
+       { SIRF_U32, offsetof(struct sirf_geodetic_nav_data, lon) },             /* 27 */
+       { SIRF_DISCARD, 4 },    /* altitude from ellipsoid */                   /* 31 */
+       { SIRF_U32, offsetof(struct sirf_geodetic_nav_data, alt_msl) },         /* 35 */
+       { SIRF_DISCARD, 1 },    /* map datum */                                 /* 39 */
+       { SIRF_U16, offsetof(struct sirf_geodetic_nav_data, ground_speed) },    /* 40 */
+       { SIRF_U16, offsetof(struct sirf_geodetic_nav_data, course) },          /* 42 */
+       { SIRF_DISCARD, 2 },    /* magnetic variation */                        /* 44 */
+       { SIRF_U16, offsetof(struct sirf_geodetic_nav_data, climb_rate) },      /* 46 */
+       { SIRF_DISCARD, 2 },    /* turn rate */                                 /* 48 */
+       { SIRF_U32, offsetof(struct sirf_geodetic_nav_data, h_error) },         /* 50 */
+       { SIRF_U32, offsetof(struct sirf_geodetic_nav_data, v_error) },         /* 54 */
+       { SIRF_DISCARD, 30 },   /* time error, h_vel error, clock_bias,
+                                  clock bias error, clock drift,
+                                  clock drift error, distance,
+                                  distance error, heading error */             /* 58 */
+       { SIRF_U8, offsetof(struct sirf_geodetic_nav_data, num_sv) },           /* 88 */
+       { SIRF_U8, offsetof(struct sirf_geodetic_nav_data, hdop) },             /* 89 */
+       { SIRF_DISCARD, 1 },    /* additional mode info */                      /* 90 */
+       { SIRF_END, 0 },                                                        /* 91 */
+};
+
+static void
+ao_sirf_parse_41(void) __reentrant
+{
+       ao_sirf_parse(&ao_sirf_data, geodetic_nav_data_packet);
+}
+
+static const struct sirf_packet_parse measured_tracker_data_packet[] = {
+       { SIRF_U16, offsetof (struct sirf_measured_tracker_data, gps_week) },   /* 1 week */
+       { SIRF_U32, offsetof (struct sirf_measured_tracker_data, gps_tow) },    /* 3 time of week */
+       { SIRF_U8, offsetof (struct sirf_measured_tracker_data, channels) },    /* 7 channels */
+       { SIRF_END, 0 },
+};
+
+static const struct sirf_packet_parse measured_sat_data_packet[] = {
+       { SIRF_U8, offsetof (struct sirf_measured_sat_data, svid) },            /* 0 SV id */
+       { SIRF_DISCARD, 2 },                                                    /* 1 azimuth, 2 elevation */
+       { SIRF_U16, offsetof (struct sirf_measured_sat_data, state) },          /* 2 state */
+       { SIRF_U8, offsetof (struct sirf_measured_sat_data, c_n_1) },           /* C/N0 1 */
+       { SIRF_DISCARD, 9 },                                                    /* C/N0 2-10 */
+       { SIRF_END, 0 },
+};
+
+static void
+ao_sirf_parse_4(void) __reentrant
+{
+       uint8_t i;
+       ao_sirf_parse(&ao_sirf_tracker_data, measured_tracker_data_packet);
+       for (i = 0; i < 12; i++)
+               ao_sirf_parse(&ao_sirf_tracker_data.sats[i], measured_sat_data_packet);
+}
+
+static void
+ao_gps_setup(void) __reentrant
+{
+       uint8_t i, k;
+       ao_serial_set_speed(AO_SERIAL_SPEED_4800);
+       for (i = 0; i < 64; i++)
+               ao_serial_putchar(0x00);
+       for (k = 0; k < 3; k++)
+               for (i = 0; i < sizeof (ao_gps_set_nmea); i++)
+                       ao_serial_putchar(ao_gps_set_nmea[i]);
+       ao_serial_set_speed(AO_SERIAL_SPEED_57600);
+       for (i = 0; i < 64; i++)
+               ao_serial_putchar(0x00);
+}
+
+static const char ao_gps_set_message_rate[] = {
+       0xa0, 0xa2, 0x00, 0x08,
+       166,
+       0,
+};
+
+void
+ao_sirf_set_message_rate(uint8_t msg, uint8_t rate)
+{
+       uint16_t        cksum = 0x00a6;
+       uint8_t         i;
+
+       for (i = 0; i < sizeof (ao_gps_set_message_rate); i++)
+               ao_serial_putchar(ao_gps_set_message_rate[i]);
+       ao_serial_putchar(msg);
+       ao_serial_putchar(rate);
+       cksum = 0xa6 + msg + rate;
+       for (i = 0; i < 4; i++)
+               ao_serial_putchar(0);
+       ao_serial_putchar((cksum >> 8) & 0x7f);
+       ao_serial_putchar(cksum & 0xff);
+       ao_serial_putchar(0xb0);
+       ao_serial_putchar(0xb3);
+}
+
+static const uint8_t sirf_disable[] = {
+       2,
+       9,
+       10,
+       27,
+       50,
+       52,
+};
+
+void
+ao_gps(void) __reentrant
+{
+       uint8_t i, k;
+       uint16_t cksum;
+
+       ao_gps_setup();
+       for (k = 0; k < 5; k++)
+       {
+               for (i = 0; i < sizeof (ao_gps_config); i++)
+                       ao_serial_putchar(ao_gps_config[i]);
+               for (i = 0; i < sizeof (sirf_disable); i++)
+                       ao_sirf_set_message_rate(sirf_disable[i], 0);
+               ao_sirf_set_message_rate(41, 1);
+               ao_sirf_set_message_rate(4, 1);
+       }
+       for (;;) {
+               /* Locate the begining of the next record */
+               while (ao_sirf_byte() != (uint8_t) 0xa0)
+                       ;
+               if (ao_sirf_byte() != (uint8_t) 0xa2)
+                       continue;
+
+               /* Length */
+               ao_sirf_len = ao_sirf_byte() << 8;
+               ao_sirf_len |= ao_sirf_byte();
+               if (ao_sirf_len > 1023)
+                       continue;
+
+               ao_sirf_cksum = 0;
+
+               /* message ID */
+               i = data_byte ();                                                       /* 0 */
+
+               switch (i) {
+               case 41:
+                       if (ao_sirf_len < 90)
+                               break;
+                       ao_sirf_parse_41();
+                       break;
+               case 4:
+                       if (ao_sirf_len < 187)
+                               break;
+                       ao_sirf_parse_4();
+                       break;
+               }
+               if (ao_sirf_len != 0)
+                       continue;
+
+               /* verify checksum and end sequence */
+               ao_sirf_cksum &= 0x7fff;
+               cksum = ao_sirf_byte() << 8;
+               cksum |= ao_sirf_byte();
+               if (ao_sirf_cksum != cksum)
+                       continue;
+               if (ao_sirf_byte() != (uint8_t) 0xb0)
+                       continue;
+               if (ao_sirf_byte() != (uint8_t) 0xb3)
+                       continue;
+
+               switch (i) {
+               case 41:
+                       ao_mutex_get(&ao_gps_mutex);
+                       ao_gps_data.hour = ao_sirf_data.utc_hour;
+                       ao_gps_data.minute = ao_sirf_data.utc_minute;
+                       ao_gps_data.second = ao_sirf_data.utc_second / 1000;
+                       ao_gps_data.flags = ((ao_sirf_data.num_sv << AO_GPS_NUM_SAT_SHIFT) & AO_GPS_NUM_SAT_MASK) | AO_GPS_RUNNING;
+                       if ((ao_sirf_data.nav_type & NAV_TYPE_GPS_FIX_TYPE_MASK) >= NAV_TYPE_4_SV_KF)
+                               ao_gps_data.flags |= AO_GPS_VALID;
+                       ao_gps_data.latitude = ao_sirf_data.lat;
+                       ao_gps_data.longitude = ao_sirf_data.lon;
+                       ao_gps_data.altitude = ao_sirf_data.alt_msl / 100;
+                       ao_gps_data.ground_speed = ao_sirf_data.ground_speed;
+                       ao_gps_data.course = ao_sirf_data.course / 200;
+                       ao_gps_data.hdop = ao_sirf_data.hdop;
+                       ao_gps_data.climb_rate = ao_sirf_data.climb_rate;
+                       if (ao_sirf_data.h_error > 6553500)
+                               ao_gps_data.h_error = 65535;
+                       else
+                               ao_gps_data.h_error = ao_sirf_data.h_error / 100;
+                       if (ao_sirf_data.v_error > 6553500)
+                               ao_gps_data.v_error = 65535;
+                       else
+                               ao_gps_data.v_error = ao_sirf_data.v_error / 100;
+                       ao_mutex_put(&ao_gps_mutex);
+                       ao_wakeup(&ao_gps_data);
+                       break;
+               case 4:
+                       ao_mutex_get(&ao_gps_mutex);
+                       ao_gps_tracking_data.channels = ao_sirf_tracker_data.channels;
+                       for (i = 0; i < 12; i++) {
+                               ao_gps_tracking_data.sats[i].svid = ao_sirf_tracker_data.sats[i].svid;
+                               ao_gps_tracking_data.sats[i].state = (uint8_t) ao_sirf_tracker_data.sats[i].state;
+                               ao_gps_tracking_data.sats[i].c_n_1 = ao_sirf_tracker_data.sats[i].c_n_1;
+                       }
+                       ao_mutex_put(&ao_gps_mutex);
+                       ao_wakeup(&ao_gps_tracking_data);
+                       break;
+               }
+       }
+}
+
+__xdata struct ao_task ao_gps_task;
+
+static void
+gps_dump(void) __reentrant
+{
+       ao_mutex_get(&ao_gps_mutex);
+       ao_gps_print(&ao_gps_data);
+       putchar('\n');
+       ao_gps_tracking_print(&ao_gps_tracking_data);
+       putchar('\n');
+       ao_mutex_put(&ao_gps_mutex);
+}
+
+__code struct ao_cmds ao_gps_cmds[] = {
+       { 'g', gps_dump,        "g                                  Display current GPS values" },
+       { 0, gps_dump, NULL },
+};
+
+void
+ao_gps_init(void)
+{
+       ao_add_task(&ao_gps_task, ao_gps, "gps");
+       ao_cmd_register(&ao_gps_cmds[0]);
+}