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678 lines
21 KiB
678 lines
21 KiB
// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- |
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/* |
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This program is free software: you can redistribute it and/or modify |
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it under the terms of the GNU General Public License as published by |
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the Free Software Foundation, either version 3 of the License, or |
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(at your option) any later version. |
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|
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This program is distributed in the hope that it will be useful, |
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but WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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GNU General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
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along with this program. If not, see <http://www.gnu.org/licenses/>. |
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*/ |
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|
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// |
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// u-blox GPS driver for ArduPilot |
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// Origin code by Michael Smith, Jordi Munoz and Jose Julio, DIYDrones.com |
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// Substantially rewitten for new GPS driver structure by Andrew Tridgell |
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// |
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#include <AP_GPS.h> |
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#include "AP_GPS_UBLOX.h" |
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#include <DataFlash.h> |
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|
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#define UBLOX_DEBUGGING 0 |
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#define UBLOX_FAKE_3DLOCK 0 |
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extern const AP_HAL::HAL& hal; |
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#if UBLOX_DEBUGGING |
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# define Debug(fmt, args ...) do {hal.console->printf("%s:%d: " fmt "\n", __FUNCTION__, __LINE__, ## args); hal.scheduler->delay(1); } while(0) |
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#else |
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# define Debug(fmt, args ...) |
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#endif |
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|
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/* |
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only do detailed hardware logging on boards likely to have more log |
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storage space |
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*/ |
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#if HAL_CPU_CLASS >= HAL_CPU_CLASS_75 |
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#define UBLOX_HW_LOGGING 1 |
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#else |
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#define UBLOX_HW_LOGGING 0 |
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#endif |
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AP_GPS_UBLOX::AP_GPS_UBLOX(AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port) : |
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AP_GPS_Backend(_gps, _state, _port), |
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_step(0), |
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_msg_id(0), |
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_payload_length(0), |
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_payload_counter(0), |
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_fix_count(0), |
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_class(0), |
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_new_position(0), |
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_new_speed(0), |
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need_rate_update(false), |
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_disable_counter(0), |
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next_fix(AP_GPS::NO_FIX), |
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rate_update_step(0), |
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_last_5hz_time(0), |
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_last_hw_status(0) |
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{ |
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// stop any config strings that are pending |
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gps.send_blob_start(state.instance, NULL, 0); |
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|
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// configure the GPS for the messages we want |
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_configure_gps(); |
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} |
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|
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/* |
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send the next step of rate updates to the GPS. This reconfigures the |
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GPS on the fly to have the right message rates. It needs to be |
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careful to only send a message if there is sufficient buffer space |
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available on the serial port to avoid it blocking the CPU |
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*/ |
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void |
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AP_GPS_UBLOX::send_next_rate_update(void) |
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{ |
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if (port->txspace() < (int16_t)(sizeof(struct ubx_header)+sizeof(struct ubx_cfg_nav_rate)+2)) { |
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// not enough space - do it next time |
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return; |
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} |
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|
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//hal.console->printf_P(PSTR("next_rate: %u\n"), (unsigned)rate_update_step); |
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switch (rate_update_step++) { |
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case 0: |
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_configure_navigation_rate(200); |
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break; |
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case 1: |
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_configure_message_rate(CLASS_NAV, MSG_POSLLH, 1); // 28+8 bytes |
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break; |
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case 2: |
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_configure_message_rate(CLASS_NAV, MSG_STATUS, 1); // 16+8 bytes |
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break; |
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case 3: |
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_configure_message_rate(CLASS_NAV, MSG_SOL, 1); // 52+8 bytes |
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break; |
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case 4: |
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_configure_message_rate(CLASS_NAV, MSG_VELNED, 1); // 36+8 bytes |
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break; |
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#if UBLOX_HW_LOGGING |
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case 5: |
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// gather MON_HW at 0.5Hz |
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_configure_message_rate(CLASS_MON, MSG_MON_HW, 2); // 64+8 bytes |
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break; |
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case 6: |
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// gather MON_HW2 at 0.5Hz |
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_configure_message_rate(CLASS_MON, MSG_MON_HW2, 2); // 24+8 bytes |
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break; |
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#endif |
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default: |
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need_rate_update = false; |
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rate_update_step = 0; |
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break; |
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} |
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} |
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|
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// Process bytes available from the stream |
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// |
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// The stream is assumed to contain only messages we recognise. If it |
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// contains other messages, and those messages contain the preamble |
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// bytes, it is possible for this code to fail to synchronise to the |
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// stream immediately. Without buffering the entire message and |
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// re-processing it from the top, this is unavoidable. The parser |
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// attempts to avoid this when possible. |
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// |
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bool |
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AP_GPS_UBLOX::read(void) |
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{ |
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uint8_t data; |
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int16_t numc; |
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bool parsed = false; |
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if (need_rate_update) { |
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send_next_rate_update(); |
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} |
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numc = port->available(); |
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for (int16_t i = 0; i < numc; i++) { // Process bytes received |
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|
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// read the next byte |
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data = port->read(); |
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reset: |
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switch(_step) { |
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|
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// Message preamble detection |
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// |
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// If we fail to match any of the expected bytes, we reset |
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// the state machine and re-consider the failed byte as |
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// the first byte of the preamble. This improves our |
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// chances of recovering from a mismatch and makes it less |
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// likely that we will be fooled by the preamble appearing |
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// as data in some other message. |
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// |
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case 1: |
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if (PREAMBLE2 == data) { |
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_step++; |
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break; |
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} |
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_step = 0; |
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Debug("reset %u", __LINE__); |
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// FALLTHROUGH |
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case 0: |
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if(PREAMBLE1 == data) |
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_step++; |
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break; |
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|
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// Message header processing |
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// |
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// We sniff the class and message ID to decide whether we |
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// are going to gather the message bytes or just discard |
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// them. |
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// |
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// We always collect the length so that we can avoid being |
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// fooled by preamble bytes in messages. |
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// |
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case 2: |
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_step++; |
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_class = data; |
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_ck_b = _ck_a = data; // reset the checksum accumulators |
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break; |
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case 3: |
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_step++; |
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_ck_b += (_ck_a += data); // checksum byte |
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_msg_id = data; |
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break; |
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case 4: |
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_step++; |
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_ck_b += (_ck_a += data); // checksum byte |
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_payload_length = data; // payload length low byte |
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break; |
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case 5: |
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_step++; |
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_ck_b += (_ck_a += data); // checksum byte |
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_payload_length += (uint16_t)(data<<8); |
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if (_payload_length > 512) { |
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Debug("large payload %u", (unsigned)_payload_length); |
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// assume very large payloads are line noise |
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_payload_length = 0; |
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_step = 0; |
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goto reset; |
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} |
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_payload_counter = 0; // prepare to receive payload |
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break; |
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// Receive message data |
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// |
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case 6: |
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_ck_b += (_ck_a += data); // checksum byte |
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if (_payload_counter < sizeof(_buffer)) { |
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_buffer.bytes[_payload_counter] = data; |
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} |
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if (++_payload_counter == _payload_length) |
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_step++; |
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break; |
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// Checksum and message processing |
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// |
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case 7: |
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_step++; |
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if (_ck_a != data) { |
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Debug("bad cka %x should be %x", data, _ck_a); |
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_step = 0; |
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goto reset; |
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} |
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break; |
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case 8: |
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_step = 0; |
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if (_ck_b != data) { |
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Debug("bad ckb %x should be %x", data, _ck_b); |
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break; // bad checksum |
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} |
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if (_parse_gps()) { |
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parsed = true; |
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} |
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} |
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} |
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return parsed; |
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} |
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// Private Methods ///////////////////////////////////////////////////////////// |
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#if UBLOX_HW_LOGGING |
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void AP_GPS_UBLOX::log_mon_hw(void) |
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{ |
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if (gps._DataFlash == NULL || !gps._DataFlash->logging_started()) { |
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return; |
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} |
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struct log_Ubx1 pkt = { |
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LOG_PACKET_HEADER_INIT(LOG_UBX1_MSG), |
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timestamp : hal.scheduler->millis(), |
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instance : state.instance, |
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noisePerMS : _buffer.mon_hw_60.noisePerMS, |
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jamInd : _buffer.mon_hw_60.jamInd, |
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aPower : _buffer.mon_hw_60.aPower, |
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agcCnt : _buffer.mon_hw_60.agcCnt, |
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}; |
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if (_payload_length == 68) { |
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pkt.noisePerMS = _buffer.mon_hw_68.noisePerMS; |
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pkt.jamInd = _buffer.mon_hw_68.jamInd; |
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pkt.aPower = _buffer.mon_hw_68.aPower; |
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pkt.agcCnt = _buffer.mon_hw_68.agcCnt; |
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} |
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gps._DataFlash->WriteBlock(&pkt, sizeof(pkt)); |
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} |
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void AP_GPS_UBLOX::log_mon_hw2(void) |
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{ |
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if (gps._DataFlash == NULL || !gps._DataFlash->logging_started()) { |
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return; |
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} |
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struct log_Ubx2 pkt = { |
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LOG_PACKET_HEADER_INIT(LOG_UBX2_MSG), |
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timestamp : hal.scheduler->millis(), |
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instance : state.instance, |
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ofsI : _buffer.mon_hw2.ofsI, |
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magI : _buffer.mon_hw2.magI, |
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ofsQ : _buffer.mon_hw2.ofsQ, |
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magQ : _buffer.mon_hw2.magQ, |
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}; |
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gps._DataFlash->WriteBlock(&pkt, sizeof(pkt)); |
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} |
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void AP_GPS_UBLOX::log_accuracy(void) { |
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if (gps._DataFlash == NULL || !gps._DataFlash->logging_started()) { |
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return; |
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} |
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struct log_Ubx3 pkt = { |
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LOG_PACKET_HEADER_INIT(LOG_UBX3_MSG), |
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timestamp : hal.scheduler->millis(), |
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instance : state.instance, |
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hAcc : state.horizontal_accuracy, |
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vAcc : state.vertical_accuracy, |
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sAcc : state.speed_accuracy |
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}; |
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gps._DataFlash->WriteBlock(&pkt, sizeof(pkt)); |
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} |
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#endif // UBLOX_HW_LOGGING |
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void AP_GPS_UBLOX::unexpected_message(void) |
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{ |
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Debug("Unexpected message 0x%02x 0x%02x", (unsigned)_class, (unsigned)_msg_id); |
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if (++_disable_counter == 0) { |
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// disable future sends of this message id, but |
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// only do this every 256 messages, as some |
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// message types can't be disabled and we don't |
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// want to get into an ack war |
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Debug("Disabling message 0x%02x 0x%02x", (unsigned)_class, (unsigned)_msg_id); |
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_configure_message_rate(_class, _msg_id, 0); |
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} |
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} |
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bool |
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AP_GPS_UBLOX::_parse_gps(void) |
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{ |
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if (_class == CLASS_ACK) { |
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Debug("ACK %u", (unsigned)_msg_id); |
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return false; |
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} |
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if (_class == CLASS_CFG && _msg_id == MSG_CFG_NAV_SETTINGS) { |
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Debug("Got settings %u min_elev %d drLimit %u\n", |
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(unsigned)_buffer.nav_settings.dynModel, |
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(int)_buffer.nav_settings.minElev, |
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(unsigned)_buffer.nav_settings.drLimit); |
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_buffer.nav_settings.mask = 0; |
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if (gps._navfilter != AP_GPS::GPS_ENGINE_NONE && |
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_buffer.nav_settings.dynModel != gps._navfilter) { |
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// we've received the current nav settings, change the engine |
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// settings and send them back |
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Debug("Changing engine setting from %u to %u\n", |
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(unsigned)_buffer.nav_settings.dynModel, (unsigned)gps._navfilter); |
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_buffer.nav_settings.dynModel = gps._navfilter; |
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_buffer.nav_settings.mask |= 1; |
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} |
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if (gps._min_elevation != -100 && |
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_buffer.nav_settings.minElev != gps._min_elevation) { |
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Debug("Changing min elevation to %d\n", (int)gps._min_elevation); |
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_buffer.nav_settings.minElev = gps._min_elevation; |
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_buffer.nav_settings.mask |= 2; |
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} |
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if (_buffer.nav_settings.mask != 0) { |
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_send_message(CLASS_CFG, MSG_CFG_NAV_SETTINGS, |
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&_buffer.nav_settings, |
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sizeof(_buffer.nav_settings)); |
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} |
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return false; |
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} |
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if (_class == CLASS_CFG && _msg_id == MSG_CFG_SBAS && gps._sbas_mode != 2) { |
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Debug("Got SBAS settings %u %u %u 0x%x 0x%x\n", |
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(unsigned)_buffer.sbas.mode, |
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(unsigned)_buffer.sbas.usage, |
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(unsigned)_buffer.sbas.maxSBAS, |
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(unsigned)_buffer.sbas.scanmode2, |
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(unsigned)_buffer.sbas.scanmode1); |
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if (_buffer.sbas.mode != gps._sbas_mode) { |
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_buffer.sbas.mode = gps._sbas_mode; |
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_send_message(CLASS_CFG, MSG_CFG_SBAS, |
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&_buffer.sbas, |
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sizeof(_buffer.sbas)); |
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} |
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} |
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#if UBLOX_HW_LOGGING |
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if (_class == CLASS_MON) { |
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if (_msg_id == MSG_MON_HW) { |
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if (_payload_length == 60 || _payload_length == 68) { |
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log_mon_hw(); |
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} |
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} else if (_msg_id == MSG_MON_HW2) { |
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if (_payload_length == 28) { |
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log_mon_hw2(); |
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} |
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} else { |
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unexpected_message(); |
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} |
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return false; |
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} |
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#endif // UBLOX_HW_LOGGING |
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|
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if (_class != CLASS_NAV) { |
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unexpected_message(); |
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return false; |
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} |
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switch (_msg_id) { |
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case MSG_POSLLH: |
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Debug("MSG_POSLLH next_fix=%u", next_fix); |
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_last_pos_time = _buffer.posllh.time; |
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state.location.lng = _buffer.posllh.longitude; |
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state.location.lat = _buffer.posllh.latitude; |
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state.location.alt = _buffer.posllh.altitude_msl / 10; |
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state.status = next_fix; |
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_new_position = true; |
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#if UBLOX_FAKE_3DLOCK |
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state.location.lng = 1491652300L; |
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state.location.lat = -353632610L; |
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state.location.alt = 58400; |
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#endif |
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state.horizontal_accuracy = _buffer.posllh.horizontal_accuracy*1.0e-3f; |
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state.vertical_accuracy = _buffer.posllh.vertical_accuracy*1.0e-3f; |
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state.have_horizontal_accuracy = true; |
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state.have_vertical_accuracy = true; |
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break; |
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case MSG_STATUS: |
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Debug("MSG_STATUS fix_status=%u fix_type=%u", |
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_buffer.status.fix_status, |
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_buffer.status.fix_type); |
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if (_buffer.status.fix_status & NAV_STATUS_FIX_VALID) { |
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if( _buffer.status.fix_type == AP_GPS_UBLOX::FIX_3D) { |
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next_fix = AP_GPS::GPS_OK_FIX_3D; |
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}else if (_buffer.status.fix_type == AP_GPS_UBLOX::FIX_2D) { |
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next_fix = AP_GPS::GPS_OK_FIX_2D; |
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}else{ |
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next_fix = AP_GPS::NO_FIX; |
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state.status = AP_GPS::NO_FIX; |
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} |
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}else{ |
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next_fix = AP_GPS::NO_FIX; |
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state.status = AP_GPS::NO_FIX; |
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} |
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#if UBLOX_FAKE_3DLOCK |
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state.status = AP_GPS::GPS_OK_FIX_3D; |
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next_fix = state.status; |
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#endif |
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break; |
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case MSG_SOL: |
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Debug("MSG_SOL fix_status=%u fix_type=%u", |
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_buffer.solution.fix_status, |
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_buffer.solution.fix_type); |
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if (_buffer.solution.fix_status & NAV_STATUS_FIX_VALID) { |
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if( _buffer.solution.fix_type == AP_GPS_UBLOX::FIX_3D) { |
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next_fix = AP_GPS::GPS_OK_FIX_3D; |
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}else if (_buffer.solution.fix_type == AP_GPS_UBLOX::FIX_2D) { |
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next_fix = AP_GPS::GPS_OK_FIX_2D; |
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}else{ |
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next_fix = AP_GPS::NO_FIX; |
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state.status = AP_GPS::NO_FIX; |
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} |
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}else{ |
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next_fix = AP_GPS::NO_FIX; |
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state.status = AP_GPS::NO_FIX; |
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} |
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state.num_sats = _buffer.solution.satellites; |
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state.hdop = _buffer.solution.position_DOP; |
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if (next_fix >= AP_GPS::GPS_OK_FIX_2D) { |
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state.last_gps_time_ms = hal.scheduler->millis(); |
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if (state.time_week == _buffer.solution.week && |
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state.time_week_ms + 200 == _buffer.solution.time) { |
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// we got a 5Hz update. This relies on the way |
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// that uBlox gives timestamps that are always |
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// multiples of 200 for 5Hz |
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_last_5hz_time = state.last_gps_time_ms; |
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} |
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state.time_week_ms = _buffer.solution.time; |
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state.time_week = _buffer.solution.week; |
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} |
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#if UBLOX_FAKE_3DLOCK |
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next_fix = state.status; |
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state.num_sats = 10; |
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state.hdop = 200; |
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state.time_week = 1721; |
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state.time_week_ms = hal.scheduler->millis() + 3*60*60*1000 + 37000; |
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state.last_gps_time_ms = hal.scheduler->millis(); |
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#endif |
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break; |
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case MSG_VELNED: |
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Debug("MSG_VELNED"); |
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_last_vel_time = _buffer.velned.time; |
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state.ground_speed = _buffer.velned.speed_2d*0.01f; // m/s |
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state.ground_course_cd = _buffer.velned.heading_2d / 1000; // Heading 2D deg * 100000 rescaled to deg * 100 |
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state.have_vertical_velocity = true; |
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state.velocity.x = _buffer.velned.ned_north * 0.01f; |
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state.velocity.y = _buffer.velned.ned_east * 0.01f; |
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state.velocity.z = _buffer.velned.ned_down * 0.01f; |
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state.have_speed_accuracy = true; |
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state.speed_accuracy = _buffer.velned.speed_accuracy*0.01f; |
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_new_speed = true; |
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break; |
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default: |
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Debug("Unexpected NAV message 0x%02x", (unsigned)_msg_id); |
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if (++_disable_counter == 0) { |
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Debug("Disabling NAV message 0x%02x", (unsigned)_msg_id); |
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_configure_message_rate(CLASS_NAV, _msg_id, 0); |
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} |
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return false; |
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} |
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|
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// we only return true when we get new position and speed data |
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// this ensures we don't use stale data |
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if (_new_position && _new_speed && _last_vel_time == _last_pos_time) { |
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_new_speed = _new_position = false; |
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_fix_count++; |
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if ((hal.scheduler->millis() - _last_5hz_time) > 15000U && !need_rate_update) { |
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// the GPS is running slow. It possibly browned out and |
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// restarted with incorrect parameters. We will slowly |
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// send out new parameters to fix it |
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need_rate_update = true; |
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rate_update_step = 0; |
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_last_5hz_time = hal.scheduler->millis(); |
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} |
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|
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if (_fix_count == 50 && gps._sbas_mode != 2) { |
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// ask for SBAS settings every 20 seconds |
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Debug("Asking for SBAS setting\n"); |
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_send_message(CLASS_CFG, MSG_CFG_SBAS, NULL, 0); |
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} |
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if (_fix_count == 100) { |
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// ask for nav settings every 20 seconds |
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Debug("Asking for engine setting\n"); |
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_send_message(CLASS_CFG, MSG_CFG_NAV_SETTINGS, NULL, 0); |
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_fix_count = 0; |
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} |
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|
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#if UBLOX_HW_LOGGING |
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log_accuracy(); |
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#endif //UBLOX_HW_LOGGING |
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|
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return true; |
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} |
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return false; |
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} |
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|
|
|
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// UBlox auto configuration |
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|
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/* |
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* update checksum for a set of bytes |
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*/ |
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void |
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AP_GPS_UBLOX::_update_checksum(uint8_t *data, uint8_t len, uint8_t &ck_a, uint8_t &ck_b) |
|
{ |
|
while (len--) { |
|
ck_a += *data; |
|
ck_b += ck_a; |
|
data++; |
|
} |
|
} |
|
|
|
|
|
/* |
|
* send a ublox message |
|
*/ |
|
void |
|
AP_GPS_UBLOX::_send_message(uint8_t msg_class, uint8_t msg_id, void *msg, uint8_t size) |
|
{ |
|
struct ubx_header header; |
|
uint8_t ck_a=0, ck_b=0; |
|
header.preamble1 = PREAMBLE1; |
|
header.preamble2 = PREAMBLE2; |
|
header.msg_class = msg_class; |
|
header.msg_id = msg_id; |
|
header.length = size; |
|
|
|
_update_checksum((uint8_t *)&header.msg_class, sizeof(header)-2, ck_a, ck_b); |
|
_update_checksum((uint8_t *)msg, size, ck_a, ck_b); |
|
|
|
port->write((const uint8_t *)&header, sizeof(header)); |
|
port->write((const uint8_t *)msg, size); |
|
port->write((const uint8_t *)&ck_a, 1); |
|
port->write((const uint8_t *)&ck_b, 1); |
|
} |
|
|
|
|
|
/* |
|
* configure a UBlox GPS for the given message rate for a specific |
|
* message class and msg_id |
|
*/ |
|
void |
|
AP_GPS_UBLOX::_configure_message_rate(uint8_t msg_class, uint8_t msg_id, uint8_t rate) |
|
{ |
|
struct ubx_cfg_msg_rate msg; |
|
msg.msg_class = msg_class; |
|
msg.msg_id = msg_id; |
|
msg.rate = rate; |
|
_send_message(CLASS_CFG, MSG_CFG_SET_RATE, &msg, sizeof(msg)); |
|
} |
|
|
|
/* |
|
* configure a UBlox GPS navigation solution rate of 200ms |
|
*/ |
|
void |
|
AP_GPS_UBLOX::_configure_navigation_rate(uint16_t rate_ms) |
|
{ |
|
struct ubx_cfg_nav_rate msg; |
|
msg.measure_rate_ms = rate_ms; |
|
msg.nav_rate = 1; |
|
msg.timeref = 0; // UTC time |
|
_send_message(CLASS_CFG, MSG_CFG_RATE, &msg, sizeof(msg)); |
|
} |
|
|
|
/* |
|
* configure a UBlox GPS for the given message rate |
|
*/ |
|
void |
|
AP_GPS_UBLOX::_configure_gps(void) |
|
{ |
|
port->begin(38400U); |
|
|
|
// start the process of updating the GPS rates |
|
need_rate_update = true; |
|
_last_5hz_time = hal.scheduler->millis(); |
|
rate_update_step = 0; |
|
|
|
// ask for the current navigation settings |
|
Debug("Asking for engine setting\n"); |
|
_send_message(CLASS_CFG, MSG_CFG_NAV_SETTINGS, NULL, 0); |
|
} |
|
|
|
|
|
/* |
|
detect a Ublox GPS. Adds one byte, and returns true if the stream |
|
matches a UBlox |
|
*/ |
|
bool |
|
AP_GPS_UBLOX::_detect(struct UBLOX_detect_state &state, uint8_t data) |
|
{ |
|
reset: |
|
switch (state.step) { |
|
case 1: |
|
if (PREAMBLE2 == data) { |
|
state.step++; |
|
break; |
|
} |
|
state.step = 0; |
|
case 0: |
|
if (PREAMBLE1 == data) |
|
state.step++; |
|
break; |
|
case 2: |
|
state.step++; |
|
state.ck_b = state.ck_a = data; |
|
break; |
|
case 3: |
|
state.step++; |
|
state.ck_b += (state.ck_a += data); |
|
break; |
|
case 4: |
|
state.step++; |
|
state.ck_b += (state.ck_a += data); |
|
state.payload_length = data; |
|
break; |
|
case 5: |
|
state.step++; |
|
state.ck_b += (state.ck_a += data); |
|
state.payload_counter = 0; |
|
break; |
|
case 6: |
|
state.ck_b += (state.ck_a += data); |
|
if (++state.payload_counter == state.payload_length) |
|
state.step++; |
|
break; |
|
case 7: |
|
state.step++; |
|
if (state.ck_a != data) { |
|
state.step = 0; |
|
goto reset; |
|
} |
|
break; |
|
case 8: |
|
state.step = 0; |
|
if (state.ck_b == data) { |
|
// a valid UBlox packet |
|
return true; |
|
} else { |
|
goto reset; |
|
} |
|
} |
|
return false; |
|
}
|
|
|