flight/modules/gpsp/gps9gpshandler.c

   1 /**
   2  ******************************************************************************
   3  *
   4  * @file       gps9gpshandler.c
   5  * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2014.
   6  * @brief      handler for GPSV9 onboard ubx gps module.
   7  *             --
   8  * @see        The GNU Public License (GPL) Version 3
   9  *
  10  *****************************************************************************/
  11 /*
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 3 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  19  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License along
  23  * with this program; if not, write to the Free Software Foundation, Inc.,
  24  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  25  */
  26
  27 #include <openpilot.h>
  28 #include <pios_struct_helper.h>
  29 #include <pios_helpers.h>
  30 #include <ubx_utils.h>
  31 #include <pios_ubx_ddc.h>
  32
  33 #include "gps9gpshandler.h"
  34 #include "gps9protocol.h"
  35
  36 uint32_t lastUnsentData = 0;
  37 uint8_t gpsBuffer[GPS_BUFFER_SIZE];
  38 uint8_t fcBuffer[FC_BUFFER_SIZE];
  39
  40 void handleGPS()
  41 {
  42     bool completeSentenceInBuffer = false;
  43     int8_t maxCount = 2;
  44
  45     do {
  46         int32_t datacounter = PIOS_UBX_DDC_GetAvailableBytes(PIOS_I2C_GPS);
  47         if (datacounter > 0) {
  48             uint8_t toRead = (uint32_t)datacounter > GPS_BUFFER_SIZE - lastUnsentData ? GPS_BUFFER_SIZE - lastUnsentData : (uint8_t)datacounter;
  49             uint8_t toSend = toRead + lastUnsentData;
  50             PIOS_UBX_DDC_ReadData(PIOS_I2C_GPS, gpsBuffer + lastUnsentData, toRead);
  51
  52             uint8_t *lastSentence;
  53             uint16_t lastSentenceLength;
  54             completeSentenceInBuffer = ubx_getLastSentence(gpsBuffer, toSend, &lastSentence, &lastSentenceLength);
  55             if (completeSentenceInBuffer) {
  56                 toSend = (uint8_t)(lastSentence - gpsBuffer + lastSentenceLength);
  57                 PIOS_COM_SendBuffer(pios_com_main_id, gpsBuffer, toSend);
  58                 // move unsent data to the beginning of gpsBuffer to be sent next time
  59                 lastUnsentData = lastUnsentData > toSend ? lastUnsentData - toSend : 0;
  60                 if (lastUnsentData > 0) {
  61                     memcpy(gpsBuffer, (gpsBuffer + toSend), lastUnsentData);
  62                 }
  63             } else {
  64                 // toss the buffer contents if it's full and there are no complete
  65                 // ublox sentences in it.  This happens if the module is sending NMEA
  66                 lastUnsentData = toSend < GPS_BUFFER_SIZE ? toSend : 0;
  67             }
  68         }
  69
  70         datacounter = PIOS_COM_ReceiveBuffer(pios_com_main_id, fcBuffer, FC_BUFFER_SIZE, 0);
  71         if (datacounter > 0) {
  72             PIOS_UBX_DDC_WriteData(PIOS_I2C_GPS, fcBuffer, datacounter);
  73         }
  74         if (maxCount) {
  75             // Note: this delay is needed as querying too quickly the UBX module's I2C(DDC)
  76             // port causes a lot of weird issues (it stops sending nav sentences)
  77             vTaskDelay(2 * configTICK_RATE_HZ / 1000);
  78         }
  79     } while (maxCount--);
  80 }
  81
  82 typedef struct {
  83     uint8_t size;
  84     const uint8_t *sentence;
  85 } ubx_init_sentence;
  86
  87
  88 void setupGPS()
  89 {
  90     CfgPrtPkt cfgprt;
  91
  92     cfgprt.fragments.data.portID       = CFG_PRT_DATA_PORTID_DDC;
  93     cfgprt.fragments.data.reserved0    = 0;
  94     cfgprt.fragments.data.txReady      = CFG_PRT_DATA_TXREADI_DISABLED;
  95     cfgprt.fragments.data.mode = CFG_PRT_DATA_MODE_ADDR;
  96     cfgprt.fragments.data.reserved3    = 0;
  97     cfgprt.fragments.data.inProtoMask  = CFG_PRT_DATA_PROTO_UBX | CFG_PRT_DATA_PROTO_NMEA | CFG_PRT_DATA_PROTO_RTCM;
  98     cfgprt.fragments.data.outProtoMask = CFG_PRT_DATA_PROTO_UBX;
  99     cfgprt.fragments.data.flags = 0;
 100     cfgprt.fragments.data.reserved5    = 0;
 101
 102     ubx_buildPacket(&cfgprt.packet, UBX_CFG_CLASS, UBX_CFG_PRT, sizeof(CfgPrtData));
 103     PIOS_UBX_DDC_WriteData(PIOS_I2C_GPS, cfgprt.packet.binarystream, sizeof(CfgPrtPkt));
 104 }