diff options
Diffstat (limited to 'src/drivers/gps/mtk.cpp')
-rw-r--r-- | src/drivers/gps/mtk.cpp | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/src/drivers/gps/mtk.cpp b/src/drivers/gps/mtk.cpp index 62941d74b..56b702ea6 100644 --- a/src/drivers/gps/mtk.cpp +++ b/src/drivers/gps/mtk.cpp @@ -48,9 +48,9 @@ MTK::MTK(const int &fd, struct vehicle_gps_position_s *gps_position) : -_fd(fd), -_gps_position(gps_position), -_mtk_revision(0) + _fd(fd), + _gps_position(gps_position), + _mtk_revision(0) { decode_init(); } @@ -73,24 +73,28 @@ MTK::configure(unsigned &baudrate) warnx("mtk: config write failed"); return -1; } + usleep(10000); if (strlen(MTK_SET_BINARY) != write(_fd, MTK_SET_BINARY, strlen(MTK_SET_BINARY))) { warnx("mtk: config write failed"); return -1; } + usleep(10000); if (strlen(SBAS_ON) != write(_fd, SBAS_ON, strlen(SBAS_ON))) { warnx("mtk: config write failed"); return -1; } + usleep(10000); if (strlen(WAAS_ON) != write(_fd, WAAS_ON, strlen(WAAS_ON))) { warnx("mtk: config write failed"); return -1; } + usleep(10000); if (strlen(MTK_NAVTHRES_OFF) != write(_fd, MTK_NAVTHRES_OFF, strlen(MTK_NAVTHRES_OFF))) { @@ -128,12 +132,15 @@ MTK::receive(unsigned timeout) handle_message(packet); return 1; } + /* in case we keep trying but only get crap from GPS */ - if (time_started + timeout*1000 < hrt_absolute_time() ) { + if (time_started + timeout * 1000 < hrt_absolute_time()) { return -1; } + j++; } + /* everything is read */ j = count = 0; } @@ -181,6 +188,7 @@ MTK::parse_char(uint8_t b, gps_mtk_packet_t &packet) if (b == MTK_SYNC1_V16) { _decode_state = MTK_DECODE_GOT_CK_A; _mtk_revision = 16; + } else if (b == MTK_SYNC1_V19) { _decode_state = MTK_DECODE_GOT_CK_A; _mtk_revision = 19; @@ -201,7 +209,7 @@ MTK::parse_char(uint8_t b, gps_mtk_packet_t &packet) add_byte_to_checksum(b); // Fill packet buffer - ((uint8_t*)(&packet))[_rx_count] = b; + ((uint8_t *)(&packet))[_rx_count] = b; _rx_count++; /* Packet size minus checksum, XXX ? */ @@ -209,14 +217,17 @@ MTK::parse_char(uint8_t b, gps_mtk_packet_t &packet) /* Compare checksum */ if (_rx_ck_a == packet.ck_a && _rx_ck_b == packet.ck_b) { ret = 1; + } else { warnx("MTK Checksum invalid"); ret = -1; } + // Reset state machine to decode next packet decode_init(); } } + return ret; } @@ -226,19 +237,22 @@ MTK::handle_message(gps_mtk_packet_t &packet) if (_mtk_revision == 16) { _gps_position->lat = packet.latitude * 10; // from degrees*1e6 to degrees*1e7 _gps_position->lon = packet.longitude * 10; // from degrees*1e6 to degrees*1e7 + } else if (_mtk_revision == 19) { _gps_position->lat = packet.latitude; // both degrees*1e7 _gps_position->lon = packet.longitude; // both degrees*1e7 + } else { warnx("mtk: unknown revision"); _gps_position->lat = 0; _gps_position->lon = 0; } + _gps_position->alt = (int32_t)(packet.msl_altitude * 10); // from cm to mm _gps_position->fix_type = packet.fix_type; _gps_position->eph_m = packet.hdop; // XXX: Check this because eph_m is in m and hdop is without unit _gps_position->epv_m = 0.0; //unknown in mtk custom mode - _gps_position->vel_m_s = ((float)packet.ground_speed)*1e-2f; // from cm/s to m/s + _gps_position->vel_m_s = ((float)packet.ground_speed) * 1e-2f; // from cm/s to m/s _gps_position->cog_rad = ((float)packet.heading) * M_DEG_TO_RAD_F * 1e-2f; //from deg *100 to rad _gps_position->satellites_visible = packet.satellites; |