Lat/Long/Alt/AltEllipsoid added.

Author: nseidle

Diff for: examples/Example3_GetPosition/Example3_GetPosition.ino

@@ -32,7 +32,7 @@ void setup()
 {
   Serial.begin(115200);
   while (!Serial); //Wait for user to open terminal
-  Serial.println("Ublox high precision accuracy example");
+  Serial.println("Reading Lat/Long Example");
 
   Wire.begin();
 
@@ -44,7 +44,6 @@ void setup()
   }
 
   Wire.setClock(400000); //Increase I2C clock speed to 400kHz
-
 }
 
 void loop()
@@ -56,14 +55,24 @@ void loop()
   //Every other second print the current 3D position accuracy
   if(millis() - lastTime > 1000)
   {
-    long lat = myGPS.getLatitude();
+    long latitude = myGPS.getLatitude();
     Serial.print("Lat: ");
-    Serial.print(lat);
+    Serial.print(latitude);
 
     long longitude = myGPS.getLongitude();
     Serial.print(" Long: ");
     Serial.print(longitude);
     Serial.println(" (degrees * 10^-7)");
+
+    long altitude = myGPS.getAltitude();
+    Serial.print(" Alt (above mean sea level): ");
+    Serial.print(altitude);
+    Serial.println(" (mm)");
+
+    long altitudeEllipsoid = myGPS.getAltitudeEllipsoid();
+    Serial.print(" AltMSL (above Ellipsoid model surface of earth): ");
+    Serial.print(altitudeEllipsoid);
+    Serial.println(" (mm)");
   }
 
 }

Diff for: src/SparkFun_Ublox_Arduino_Library.cpp

@@ -649,7 +649,7 @@ uint32_t SFE_UBLOX_GPS::getPositionAccuracy(uint16_t maxWait)
 }
 //Get the current latitude in degrees
 //Returns a long representing the number of degrees *10^-7
-uint32_t SFE_UBLOX_GPS::getLatitude(uint16_t maxWait)
+int32_t SFE_UBLOX_GPS::getLatitude(uint16_t maxWait)
 {
 	//Query the module for the latest lat/long
 	packetCfg.cls = UBX_CLASS_NAV;
@@ -671,7 +671,7 @@ uint32_t SFE_UBLOX_GPS::getLatitude(uint16_t maxWait)
 
 //Get the current longitude in degrees
 //Returns a long representing the number of degrees *10^-7
-uint32_t SFE_UBLOX_GPS::getLongitude(uint16_t maxWait)
+int32_t SFE_UBLOX_GPS::getLongitude(uint16_t maxWait)
 {
 	//Query the module for the latest lat/long
 	packetCfg.cls = UBX_CLASS_NAV;
@@ -689,4 +689,50 @@ uint32_t SFE_UBLOX_GPS::getLongitude(uint16_t maxWait)
 	pos |= payloadCfg[7] << 8*3;
 
 	return(pos);
+}
+
+//Get the current altitude in mm according to the Ellipsoid model. 
+//Ellipsoid model: https://www.esri.com/news/arcuser/0703/geoid1of3.html
+//Difference between Ellipsoid Model and Mean Sea Level: https://eos-gnss.com/elevation-for-beginners/
+int32_t SFE_UBLOX_GPS::getAltitudeEllipsoid(uint16_t maxWait)
+{
+	//Send packet with only CLS and ID, length of zero. This will cause the module to respond with the contents of that CLS/ID.
+	packetCfg.cls = UBX_CLASS_NAV;
+	packetCfg.id = UBX_NAV_POSLLH;
+	packetCfg.len = 0;
+
+	if(sendCommand(packetCfg, maxWait) == false)
+		return(0); //If command send fails then bail
+
+	//We got a response, now parse the byte fields
+	uint32_t alt = 0;
+	alt |= payloadCfg[12] << 8*0;
+	alt |= payloadCfg[13] << 8*1;
+	alt |= payloadCfg[14] << 8*2;
+	alt |= payloadCfg[15] << 8*3;
+
+	return(alt);
+}
+
+//Get the current altitude in mm according to mean sea level
+//Ellipsoid model: https://www.esri.com/news/arcuser/0703/geoid1of3.html
+//Difference between Ellipsoid Model and Mean Sea Level: https://eos-gnss.com/elevation-for-beginners/
+int32_t SFE_UBLOX_GPS::getAltitude(uint16_t maxWait)
+{
+	//Send packet with only CLS and ID, length of zero. This will cause the module to respond with the contents of that CLS/ID.
+	packetCfg.cls = UBX_CLASS_NAV;
+	packetCfg.id = UBX_NAV_POSLLH;
+	packetCfg.len = 0;
+
+	if(sendCommand(packetCfg, maxWait) == false)
+		return(0); //If command send fails then bail
+
+	//We got a response, now parse the byte fields
+	uint32_t alt = 0;
+	alt |= payloadCfg[16] << 8*0;
+	alt |= payloadCfg[17] << 8*1;
+	alt |= payloadCfg[18] << 8*2;
+	alt |= payloadCfg[19] << 8*3;
+
+	return(alt);
 }

Diff for: src/SparkFun_Ublox_Arduino_Library.h

@@ -174,8 +174,10 @@ class SFE_UBLOX_GPS
 
 	uint32_t getPositionAccuracy(uint16_t maxWait = 500); //Returns the 3D accuracy of the current high-precision fix, in mm. Supported on NEO-M8P, ZED-F9P,
 
-	uint32_t getLatitude(uint16_t maxWait = 250); //Returns the current latitude in degrees * 10^-7. Auto selects between HighPrecision and Regular depending on ability of module.
-	uint32_t getLongitude(uint16_t maxWait = 250); //Returns the current longitude in degrees * 10-7. Auto selects between HighPrecision and Regular depending on ability of module.
+	int32_t getLatitude(uint16_t maxWait = 250); //Returns the current latitude in degrees * 10^-7. Auto selects between HighPrecision and Regular depending on ability of module.
+	int32_t getLongitude(uint16_t maxWait = 250); //Returns the current longitude in degrees * 10-7. Auto selects between HighPrecision and Regular depending on ability of module.
+	int32_t getAltitude(uint16_t maxWait = 250); //Returns the current altitude in mm above mean sea level (most common output of GPS receivers).
+	int32_t getAltitudeEllipsoid(uint16_t maxWait = 250); //Returns the current altitude in mm, ellipsoid model.
 
 	struct svinStructure {
 		boolean active;