AP_GPS: cope with different MON-HW message size in u-Blox Neo7

libraries/AP_GPS/AP_GPS_UBLOX.cpp

@@ -295,10 +295,15 @@ void AP_GPS_UBLOX::log_mon_hw(void)
         LOG_PACKET_HEADER_INIT(LOG_MSG_UBX1),
         timestamp  : hal.scheduler->millis(),
         instance   : state.instance,
-        noisePerMS : _buffer.mon_hw.noisePerMS,
-        jamInd     : _buffer.mon_hw.jamInd,
-        aPower     : _buffer.mon_hw.aPower
+        noisePerMS : _buffer.mon_hw_60.noisePerMS,
+        jamInd     : _buffer.mon_hw_60.jamInd,
+        aPower     : _buffer.mon_hw_60.aPower
     };
+    if (_payload_length == 68) {
+        pkt.noisePerMS = _buffer.mon_hw_68.noisePerMS;
+        pkt.jamInd     = _buffer.mon_hw_68.jamInd;
+        pkt.aPower     = _buffer.mon_hw_68.aPower;
+    }
     gps._DataFlash->WriteBlock(&pkt, sizeof(pkt));    
 }
 
@@ -364,9 +369,13 @@ AP_GPS_UBLOX::_parse_gps(void)
 #if UBLOX_HW_LOGGING
     if (_class == CLASS_MON) {
         if (_msg_id == MSG_MON_HW) {
-            log_mon_hw();
+            if (_payload_length == 60 || _payload_length == 68) {
+                log_mon_hw();
+            }
         } else if (_msg_id == MSG_MON_HW2) {
-            log_mon_hw2();            
+            if (_payload_length == 28) {
+                log_mon_hw2();  
+            }
         } else {
             unexpected_message();
         }

libraries/AP_GPS/AP_GPS_UBLOX.h

@@ -135,7 +135,28 @@ private:
         uint32_t speed_accuracy;
         uint32_t heading_accuracy;
     };
-    struct PACKED ubx_mon_hw {
+    // Lea6 uses a 60 byte message
+    struct PACKED ubx_mon_hw_60 {
+        uint32_t pinSel;
+        uint32_t pinBank;
+        uint32_t pinDir;
+        uint32_t pinVal;
+        uint16_t noisePerMS;
+        uint16_t agcCnt;
+        uint8_t aStatus;
+        uint8_t aPower;
+        uint8_t flags;
+        uint8_t reserved1;
+        uint32_t usedMask;
+        uint8_t VP[17];
+        uint8_t jamInd;
+        uint16_t reserved3;
+        uint32_t pinIrq;
+        uint32_t pullH;
+        uint32_t pullL;
+    };
+    // Neo7 uses a 68 byte message
+    struct PACKED ubx_mon_hw_68 {
         uint32_t pinSel;
         uint32_t pinBank;
         uint32_t pinDir;
@@ -173,7 +194,8 @@ private:
         ubx_nav_solution solution;
         ubx_nav_velned velned;
         ubx_cfg_nav_settings nav_settings;
-        ubx_mon_hw mon_hw;
+        ubx_mon_hw_60 mon_hw_60;
+        ubx_mon_hw_68 mon_hw_68;
         ubx_mon_hw2 mon_hw2;
         uint8_t bytes[];
     } _buffer;