Clarify values not saved by OTOS in examples

Author: sfe-SparkFro

examples/Example2_SetUnits/Example2_SetUnits.ino

@@ -23,7 +23,9 @@ void setup()
 
     // Set the desired units for linear and angular measurements. Can be either
     // meters or inches for linear, and radians or degrees for angular. If not
-    // set, the default is inches and degrees.
+    // set, the default is inches and degrees. Note that this setting is not
+    // stored in the sensor, it's part of the library, so you need to set at the
+    // start of all your programs.
     myOtos.setLinearUnit(kOtosLinearUnitMeters);
     // myOtos.setLinearUnit(kOtosLinearUnitInches);
     myOtos.setAngularUnit(kOtosAngularUnitRadians);

examples/Example3_Calibration/Example3_Calibration.ino

@@ -22,13 +22,15 @@ void setup()
     Serial.println("OTOS connected!");
 
     // The IMU on the OTOS includes a gyroscope and accelerometer, which could
-    // have an offset. The OTOS performs a quick calibration when it powers up,
-    // but it is recommended to perform a more thorough calibration at the start
-    // of your programs. Note that the sensor must be completely stationary and
-    // flat during calibration! When calling calibrateImu(), you can specify the
-    // number of samples to take and whether to wait until the calibration is
-    // complete. If no parameters are provided, it will take 255 samples and
-    // wait until done; each sample takes about 1.2ms, so about 306ms total
+    // have an offset. Note that as of firmware version 1.0, the calibration
+    // will be lost after a power cycle; the OTOS performs a quick calibration
+    // when it powers up, but it is recommended to perform a more thorough
+    // calibration at the start of all your programs. Note that the sensor must
+    // be completely stationary and flat during calibration! When calling
+    // calibrateImu(), you can specify the number of samples to take and whether
+    // to wait until the calibration is complete. If no parameters are provided,
+    // it will take 255 samples and wait until done; each sample takes about
+    // 1.2ms, so about 306ms total
     myOtos.calibrateImu();
     // myOtos.calibrateImu(255, true);
 

examples/Example4_SetOffsetAndPosition/Example4_SetOffsetAndPosition.ino

@@ -23,7 +23,9 @@ void setup()
 
     // Here you can set the offset for the sensor relative to the center of the
     // robot. The units default to inches and degrees, but if you want to use
-    // different units, specify them before setting the offset! For example, if
+    // different units, specify them before setting the offset! Note that as of
+    // firmware version 1.0, these values will be lost after a power cycle, so
+    // you will need to set them each time you power up the sensor. For example, if
     // the sensor is mounted 5 inches to the left (negative X) and 10 inches
     // forward (positive Y) of the center of the robot, and mounted 90 degrees
     // clockwise (negative rotation) from the robot's orientation, the offset