Merge pull request #3410 from meshtastic/gnss-l76b

(1/3) Support L76B GNSS chip found on pico waveshare shield.

platformio.ini

@@ -78,7 +78,7 @@ lib_deps =
   https://github.com/meshtastic/esp8266-oled-ssd1306.git#ee628ee6c9588d4c56c9e3da35f0fc9448ad54a8 ; ESP8266_SSD1306
   mathertel/OneButton@^2.5.0 ; OneButton library for non-blocking button debounce
   https://github.com/meshtastic/arduino-fsm.git#7db3702bf0cfe97b783d6c72595e3f38e0b19159
-  https://github.com/meshtastic/TinyGPSPlus.git#2044b2c51e91ab4cd8cc93b15e40658cd808dd06
+  https://github.com/meshtastic/TinyGPSPlus.git#f9f4fef2183514aa52be91d714c1455dd6f26e45
   https://github.com/meshtastic/ArduinoThread.git#72921ac222eed6f526ba1682023cee290d9aa1b3
   nanopb/Nanopb@^0.4.7
   erriez/ErriezCRC32@^1.0.1

src/gps/GPS.cpp

@@ -290,6 +290,26 @@ bool GPS::setup()
             // Switch to Vehicle Mode, since SoftRF enables Aviation < 2g
             _serial_gps->write("$PCAS11,3*1E\r\n");
             delay(250);
+        } else if (gnssModel == GNSS_MODEL_MTK_L76B) {
+            // Waveshare Pico-GPS hat uses the L76B with 9600 baud
+            // Initialize the L76B Chip, use GPS + GLONASS
+            // See note in L76_Series_GNSS_Protocol_Specification, chapter 3.29
+            _serial_gps->write("$PMTK353,1,1,0,0,0*2B\r\n");
+            // Above command will reset the GPS and takes longer before it will accept new commands
+            delay(1000);
+            // only ask for RMC and GGA (GNRMC and GNGGA)
+            // See note in L76_Series_GNSS_Protocol_Specification, chapter 2.1
+            _serial_gps->write("$PMTK314,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0*28\r\n");
+            delay(250);
+            // Enable SBAS
+            _serial_gps->write("$PMTK301,2*2E\r\n");
+            delay(250);
+            // Enable PPS for 2D/3D fix only
+            _serial_gps->write("$PMTK285,3,100*3F\r\n");
+            delay(250);
+            // Switch to Fitness Mode, for running and walking purpose with low speed (<5 m/s)
+            _serial_gps->write("$PMTK886,1*29\r\n");
+            delay(250);
         } else if (gnssModel == GNSS_MODEL_UC6580) {
             // The Unicore UC6580 can use a lot of sat systems, enable it to
             // use GPS L1 & L5 + BDS B1I & B2a + GLONASS L1 + GALILEO E1 & E5a + SBAS
@@ -625,17 +645,27 @@ void GPS::setGPSPower(bool on, bool standbyOnly, uint32_t sleepTime)
         return;
     }
 #endif
-#ifdef PIN_GPS_STANDBY // Specifically the standby pin for L76K and clones
+#ifdef PIN_GPS_STANDBY // Specifically the standby pin for L76B, L76K and clones
     if (on) {
         LOG_INFO("Waking GPS\n");
         pinMode(PIN_GPS_STANDBY, OUTPUT);
+        // Some PCB's use an inverse logic due to a transistor driver
+        // Example for this is the Pico-Waveshare Lora+GPS HAT
+#ifdef PIN_GPS_STANDBY_INVERTED
+        digitalWrite(PIN_GPS_STANDBY, 0);
+#else
         digitalWrite(PIN_GPS_STANDBY, 1);
+#endif
         return;
     } else {
         LOG_INFO("GPS entering sleep\n");
         // notifyGPSSleep.notifyObservers(NULL);
         pinMode(PIN_GPS_STANDBY, OUTPUT);
+#ifdef PIN_GPS_STANDBY_INVERTED
+        digitalWrite(PIN_GPS_STANDBY, 1);
+#else
         digitalWrite(PIN_GPS_STANDBY, 0);
+#endif
         return;
     }
 #endif
@@ -916,7 +946,7 @@ GnssModel_t GPS::probe(int serialSpeed)
     uint8_t buffer[768] = {0};
     delay(100);
 
-    // Close all NMEA sentences , Only valid for MTK platform
+    // Close all NMEA sentences , Only valid for L76K MTK platform
     _serial_gps->write("$PCAS03,0,0,0,0,0,0,0,0,0,0,,,0,0*02\r\n");
     delay(20);
 
@@ -928,6 +958,18 @@ GnssModel_t GPS::probe(int serialSpeed)
         return GNSS_MODEL_MTK;
     }
 
+    // Close all NMEA sentences, valid for L76B MTK platform (Waveshare Pico GPS)
+    _serial_gps->write("$PMTK514,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0*2E\r\n");
+    delay(20);
+
+    // Get version information
+    clearBuffer();
+    _serial_gps->write("$PMTK605*31\r\n");
+    if (getACK("Quectel-L76B", 500) == GNSS_RESPONSE_OK) {
+        LOG_INFO("L76B GNSS init succeeded, using L76B GNSS Module\n");
+        return GNSS_MODEL_MTK_L76B;
+    }
+
     uint8_t cfg_rate[] = {0xB5, 0x62, 0x06, 0x08, 0x00, 0x00, 0x00, 0x00};
     UBXChecksum(cfg_rate, sizeof(cfg_rate));
     clearBuffer();
@@ -1109,7 +1151,6 @@ GPS *GPS::createGps()
         LOG_DEBUG("Using GPIO%d for GPS RX\n", new_gps->rx_gpio);
         LOG_DEBUG("Using GPIO%d for GPS TX\n", new_gps->tx_gpio);
         _serial_gps->begin(GPS_BAUDRATE, SERIAL_8N1, new_gps->rx_gpio, new_gps->tx_gpio);
-
 #else
         _serial_gps->begin(GPS_BAUDRATE);
 #endif
@@ -1169,6 +1210,10 @@ bool GPS::factoryReset()
         // _serial_gps->write(_message_CFG_RST_COLDSTART, sizeof(_message_CFG_RST_COLDSTART));
         // delay(1000);
     } else {
+        // fire this for good measure, if we have an L76B - won't harm other devices.
+        _serial_gps->write("$PMTK104*37\r\n");
+        // No PMTK_ACK for this command.
+        delay(100);
         // send the UBLOX Factory Reset Command regardless of detect state, something is very wrong, just assume it's UBLOX.
         // Factory Reset
         byte _message_reset[] = {0xB5, 0x62, 0x06, 0x09, 0x0D, 0x00, 0xFF, 0xFB, 0x00, 0x00, 0x00,

src/gps/GPS.h

@@ -20,12 +20,7 @@ struct uBloxGnssModelInfo {
     char extension[10][30];
 };
 
-typedef enum {
-    GNSS_MODEL_MTK,
-    GNSS_MODEL_UBLOX,
-    GNSS_MODEL_UC6580,
-    GNSS_MODEL_UNKNOWN,
-} GnssModel_t;
+typedef enum { GNSS_MODEL_MTK, GNSS_MODEL_UBLOX, GNSS_MODEL_UC6580, GNSS_MODEL_UNKNOWN, GNSS_MODEL_MTK_L76B } GnssModel_t;
 
 typedef enum {
     GNSS_RESPONSE_NONE,
@@ -92,8 +87,11 @@ class GPS : private concurrency::OSThread
 
   public:
     /** If !NULL we will use this serial port to construct our GPS */
+#if defined(RPI_PICO_WAVESHARE)
+    static SerialUART *_serial_gps;
+#else
     static HardwareSerial *_serial_gps;
-
+#endif
     static uint8_t _message_PMREQ[];
     static uint8_t _message_PMREQ_10[];
     static const uint8_t _message_CFG_RXM_PSM[];