Files
smartweatherstation_v2.0/lib/SparkFun u-blox Arduino Library/examples/ZED-F9P/Example10_GetHighPrecisionPositionAndAccuracy/Example10_GetHighPrecisionPositionAndAccuracy.ino
2025-07-08 08:54:35 +08:00

155 lines
6.6 KiB
C++

/*
Get the high precision geodetic solution for latitude and longitude
By: Nathan Seidle
Modified by: Steven Rowland and Paul Clark
SparkFun Electronics
Date: April 17th, 2020
License: MIT. See license file for more information but you can
basically do whatever you want with this code.
This example shows how to inspect the accuracy of the high-precision
positional solution. Please see below for information about the units.
Feel like supporting open source hardware?
Buy a board from SparkFun!
ZED-F9P RTK2: https://www.sparkfun.com/products/15136
NEO-M8P RTK: https://www.sparkfun.com/products/15005
Hardware Connections:
Plug a Qwiic cable into the GPS and a BlackBoard
If you don't have a platform with a Qwiic connection use the SparkFun Qwiic Breadboard Jumper (https://www.sparkfun.com/products/14425)
Open the serial monitor at 115200 baud to see the output
*/
#include <Wire.h> //Needed for I2C to GPS
#include "SparkFun_Ublox_Arduino_Library.h" //http://librarymanager/All#SparkFun_u-blox_GNSS
SFE_UBLOX_GPS myGPS;
long lastTime = 0; //Simple local timer. Limits amount if I2C traffic to Ublox module.
void setup()
{
Serial.begin(115200);
while (!Serial); //Wait for user to open terminal
Wire.begin();
//myGPS.enableDebugging(Serial);
if (myGPS.begin(Wire) == false) //Connect to the Ublox module using Wire port
{
Serial.println(F("Ublox GPS not detected at default I2C address. Please check wiring. Freezing."));
while (1);
}
myGPS.setI2COutput(COM_TYPE_UBX); //Set the I2C port to output UBX only (turn off NMEA noise)
myGPS.setNavigationFrequency(20); //Set output to 20 times a second
byte rate = myGPS.getNavigationFrequency(); //Get the update rate of this module
Serial.print("Current update rate: ");
Serial.println(rate);
//myGPS.saveConfiguration(); //Save the current settings to flash and BBR
}
void loop()
{
//Query module only every second. Doing it more often will just cause I2C traffic.
//The module only responds when a new position is available
if (millis() - lastTime > 1000)
{
lastTime = millis(); //Update the timer
// getHighResLatitude: returns the latitude from HPPOSLLH as an int32_t in degrees * 10^-7
// getHighResLatitudeHp: returns the high resolution component of latitude from HPPOSLLH as an int8_t in degrees * 10^-9
// getHighResLongitude: returns the longitude from HPPOSLLH as an int32_t in degrees * 10^-7
// getHighResLongitudeHp: returns the high resolution component of longitude from HPPOSLLH as an int8_t in degrees * 10^-9
// getElipsoid: returns the height above ellipsoid as an int32_t in mm
// getElipsoidHp: returns the high resolution component of the height above ellipsoid as an int8_t in mm * 10^-1
// getMeanSeaLevel: returns the height above mean sea level as an int32_t in mm
// getMeanSeaLevelHp: returns the high resolution component of the height above mean sea level as an int8_t in mm * 10^-1
// getHorizontalAccuracy: returns the horizontal accuracy estimate from HPPOSLLH as an uint32_t in mm * 10^-1
// If you want to use the high precision latitude and longitude with the full 9 decimal places
// you will need to use a 64-bit double - which is not supported on all platforms
// To allow this example to run on standard platforms, we cheat by converting lat and lon to integer and fractional degrees
// The high resolution altitudes can be converted into standard 32-bit float
// First, let's collect the position data
int32_t latitude = myGPS.getHighResLatitude();
int8_t latitudeHp = myGPS.getHighResLatitudeHp();
int32_t longitude = myGPS.getHighResLongitude();
int8_t longitudeHp = myGPS.getHighResLongitudeHp();
int32_t ellipsoid = myGPS.getElipsoid();
int8_t ellipsoidHp = myGPS.getElipsoidHp();
int32_t msl = myGPS.getMeanSeaLevel();
int8_t mslHp = myGPS.getMeanSeaLevelHp();
uint32_t accuracy = myGPS.getHorizontalAccuracy();
// Defines storage for the lat and lon units integer and fractional parts
int32_t lat_int; // Integer part of the latitude in degrees
int32_t lat_frac; // Fractional part of the latitude
int32_t lon_int; // Integer part of the longitude in degrees
int32_t lon_frac; // Fractional part of the longitude
// Calculate the latitude and longitude integer and fractional parts
lat_int = latitude / 10000000; // Convert latitude from degrees * 10^-7 to Degrees
lat_frac = latitude - (lat_int * 10000000); // Calculate the fractional part of the latitude
lat_frac = (lat_frac * 100) + latitudeHp; // Now add the high resolution component
if (lat_frac < 0) // If the fractional part is negative, remove the minus sign
{
lat_frac = 0 - lat_frac;
}
lon_int = longitude / 10000000; // Convert latitude from degrees * 10^-7 to Degrees
lon_frac = longitude - (lon_int * 10000000); // Calculate the fractional part of the longitude
lon_frac = (lon_frac * 100) + longitudeHp; // Now add the high resolution component
if (lon_frac < 0) // If the fractional part is negative, remove the minus sign
{
lon_frac = 0 - lon_frac;
}
// Print the lat and lon
Serial.print("Lat (deg): ");
Serial.print(lat_int); // Print the integer part of the latitude
Serial.print(".");
Serial.print(lat_frac); // Print the fractional part of the latitude
Serial.print(", Lon (deg): ");
Serial.print(lon_int); // Print the integer part of the latitude
Serial.print(".");
Serial.println(lon_frac); // Print the fractional part of the latitude
// Now define float storage for the heights and accuracy
float f_ellipsoid;
float f_msl;
float f_accuracy;
// Calculate the height above ellipsoid in mm * 10^-1
f_ellipsoid = (ellipsoid * 10) + ellipsoidHp;
// Now convert to m
f_ellipsoid = f_ellipsoid / 10000.0; // Convert from mm * 10^-1 to m
// Calculate the height above mean sea level in mm * 10^-1
f_msl = (msl * 10) + mslHp;
// Now convert to m
f_msl = f_msl / 10000.0; // Convert from mm * 10^-1 to m
// Convert the horizontal accuracy (mm * 10^-1) to a float
f_accuracy = accuracy;
// Now convert to m
f_accuracy = f_accuracy / 10000.0; // Convert from mm * 10^-1 to m
// Finally, do the printing
Serial.print("Ellipsoid (m): ");
Serial.print(f_ellipsoid, 4); // Print the ellipsoid with 4 decimal places
Serial.print(", Mean Sea Level(m): ");
Serial.print(f_msl, 4); // Print the mean sea level with 4 decimal places
Serial.print(", Accuracy (m): ");
Serial.println(f_accuracy, 4); // Print the accuracy with 4 decimal places
}
}