Add Example24

Author: PaulZC

examples/Example24_MeasurementAndNavigationRate/Example24_MeasurementAndNavigationRate.ino

@@ -0,0 +1,123 @@
+/*
+  Demonstrate get/setMeasurementRate and get/setNavigationRate
+  By: Paul Clark
+  SparkFun Electronics
+  Date: March 30th, 2021
+  License: MIT. See license file for more information but you can
+  basically do whatever you want with this code.
+
+  This example shows how to slow down the measurement and navigation rates.
+  This should run on any GNSS module but has only been tested on the ZED_F9P and ZOE_M8Q.
+
+  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
+  SAM-M8Q: https://www.sparkfun.com/products/15106
+
+  Hardware Connections:
+  Plug a Qwiic cable into the GNSS 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 GNSS
+
+#include <SparkFun_u-blox_GNSS_Arduino_Library.h> //http://librarymanager/All#SparkFun_u-blox_GNSS
+SFE_UBLOX_GNSS myGNSS;
+
+unsigned long lastTime = 0; //Simple local timer. Used to calc the message interval.
+
+void setup()
+{
+  Serial.begin(115200);
+  while (!Serial); //Wait for user to open terminal
+  Serial.println("SparkFun u-blox Example");
+
+  Wire.begin();
+
+  //myGNSS.enableDebugging(); // Uncomment this line to enable helpful debug messages on Serial
+
+  if (myGNSS.begin() == false) //Connect to the u-blox module using Wire port
+  {
+    Serial.println(F("u-blox GNSS not detected at default I2C address. Please check wiring. Freezing."));
+    while (1);
+  }
+
+  // Uncomment the next line if you need to completely reset your module
+  //myGNSS.factoryDefault(); delay(5000); // Reset everything and wait while the module restarts
+
+  myGNSS.setI2COutput(COM_TYPE_UBX); //Set the I2C port to output UBX only (turn off NMEA noise)
+
+  // Begin by printing the current measurement rate and navigation rate
+
+  uint16_t rate = myGNSS.getMeasurementRate(); //Get the measurement rate of this module
+  Serial.print("Current measurement interval (ms): ");
+  Serial.println(rate);
+
+  rate = myGNSS.getNavigationRate(); //Get the navigation rate of this module
+  Serial.print("Current navigation ratio (cycles): ");
+  Serial.println(rate);
+
+  // The measurement rate is the elapsed time between GNSS measurements, which defines the rate
+  // e.g. 100 ms => 10 Hz, 1000 ms => 1 Hz, 10000 ms => 0.1 Hz.
+  // Let's set the measurement rate (interval) to 5 seconds = 5000 milliseconds
+  if (myGNSS.setMeasurementRate(5000) == false)
+  {
+    Serial.println(F("Could not set the measurement rate. Freezing."));
+    while (1);
+  }
+
+  // setMeasurementRate will set i2cPollingWait to a quarter of the interval
+  // Let's override that so we can poll the module more frequently and avoid timeouts
+  myGNSS.setI2CpollingWait(25); // Set i2cPollingWait to 25ms
+
+  // The navigation rate is the ratio between the number of measurements and the number of navigation solutions
+  // e.g. 5 means five measurements for every navigation solution. Maximum value is 127
+  // Let's set the navigation rate (ratio) to 12 to produce a solution every minute
+  if (myGNSS.setNavigationRate(12) == false)
+  {
+    Serial.println(F("Could not set the navigation rate. Freezing."));
+    while (1);
+  }
+
+  // Another trick we can use is to mark the CFG RATE data as stale so we can be sure we read fresh data
+  myGNSS.packetUBXCFGRATE->moduleQueried.moduleQueried.all = 0; // Mark all of the CFG RATE data as stale
+
+  // Read and print the updated measurement rate and navigation rate
+
+  rate = myGNSS.getMeasurementRate(); //Get the measurement rate of this module
+  Serial.print("New measurement interval (ms): ");
+  Serial.println(rate);
+
+  rate = myGNSS.getNavigationRate(); //Get the navigation rate of this module
+  Serial.print("New navigation ratio (cycles): ");
+  Serial.println(rate);
+
+  lastTime = millis();
+}
+
+void loop()
+{
+  // i2cPollingWait will prevent us from thrashing the I2C bus
+
+  if (myGNSS.getPVT()) //Check for new Position, Velocity, Time data. getPVT returns true if new data is available.
+  {    
+      long latitude = myGNSS.getLatitude();
+      Serial.print(F("Lat: "));
+      Serial.print(latitude);
+
+      long longitude = myGNSS.getLongitude();
+      Serial.print(F(" Long: "));
+      Serial.print(longitude);
+
+      //Calculate the interval since the last message
+      Serial.print(F(" Interval: "));
+      Serial.print(((float)(millis() - lastTime)) / 1000.0, 2);
+      Serial.print(F("s"));
+
+      Serial.println();
+
+      lastTime = millis(); //Update lastTime
+  }
+}

src/SparkFun_u-blox_GNSS_Arduino_Library.h

@@ -1170,7 +1170,7 @@ class SFE_UBLOX_GNSS
 	//Limit checking of new data to every X ms
 	//If we are expecting an update every X Hz then we should check every half that amount of time
 	//Otherwise we may block ourselves from seeing new data
-	uint8_t i2cPollingWait = 100; //Default to 100ms. Adjusted when user calls setNavigationFrequency() or setHNRNavigationRate()
+	uint8_t i2cPollingWait = 100; //Default to 100ms. Adjusted when user calls setNavigationFrequency() or setHNRNavigationRate() or setMeasurementRate()
 
 	unsigned long lastCheck = 0;