faces/pulsometer: document the advanced pulsometer

Thoroughly document the new advanced pulsometer watch face
by describing what it is and how it works.

1 files changed, 34 insertions, 22 deletions

diff --git a/movement/watch_faces/complication/pulsometer_face.h b/movement/watch_faces/complication/pulsometer_face.h
index 61294d42..b5c87db7 100644
--- a/movement/watch_faces/complication/pulsometer_face.h
+++ b/movement/watch_faces/complication/pulsometer_face.h
@@ -28,28 +28,40 @@
 /*
  * PULSOMETER face
  *
- * The Pulsometer is an implementation of a sort of a classic mechanical
- * watch complication. A classic pulsometer complication involves a
- * chronograph with a scale calibrated for counting a certain number of
- * heartbeats (often 30). You start it and begin counting heartbeats, and
- * stop it after counting the specified number of beats. Once stopped,
- * the needle will point to your heart rate.
- * 
- * The pulsometer on Sensor Watch flashes its instructions at launch:
- * “Hold Alarm + count 30 beats.” Using the hand on the side where you wear
- * your watch, touch your carotid artery (in your neck) and feel for your
- * pulse. Once you find it, use your other hand to press and hold the Alarm
- * button, and count your heartbeats. When you reach 30 beats, release the
- * Alarm button. The display will show a number such as “60 bpm”; this is
- * your heart rate in beats per minute.
- * 
- * Two notes:
- *  o For the first few seconds of a measurement, the display will read “Hi”.
- *    This indicates that it’s too early for the measured value to be a valid
- *    heart rate. Once the measurement is below 240 bpm, the display will update.
- *  o If you hold the button down for more than 45 seconds, the display will
- *    read “Lo”. If it took this long for you to count 30 heartbeats, this
- *    indicates that your heart rate is below 40 beats per minute.
+ * The pulsometer implements a classic mechanical watch complication.
+ * A mechanical pulsometer involves a chronograph with a scale that
+ * allows the user to compute the number of heart beats per minute
+ * in less time. The scale is calibrated, or graduated, for a fixed
+ * number of heart beats, most often 30. The user starts the chronograph
+ * and simultaneously begins counting the heart beats. The movement of
+ * the chronograph's seconds hand over time automatically performs the
+ * computations required. When the calibrated number of heart beats
+ * is reached, the chronograph is stopped and the seconds hand shows
+ * the heart rate.
+ *
+ * The Sensor Watch pulsometer improves this design with user calibration:
+ * it can be graduated to any value between 1 and 39 pulsations per minute.
+ * The default is still 30, mirroring the classic pulsometer calibration.
+ * This feature allows the user to reconfigure the pulsometer to count
+ * many other types of periodic minutely events, making it more versatile.
+ * For example, it can be set to 5 respirations per minute to turn it into
+ * an asthmometer, a nearly identical mechanical watch complication
+ * that doctors might use to quickly measure respiratory rate.
+ *
+ * To use the pulsometer, hold the ALARM button and count the pulses.
+ * When the calibrated number of pulses is reached, release the button.
+ * The display will show the number of pulses per minute.
+ *
+ * In order to measure heart rate, feel for a pulse using the hand with
+ * the watch while holding the button down with the other.
+ * The pulse can be easily felt on the carotid artery of the neck.
+ *
+ * In order to measure breathing rate, simply hold the ALARM button
+ * and count the number of breaths.
+ *
+ * To calibrate the pulsometer, press LIGHT
+ * to cycle to the next integer calibration.
+ * Long press LIGHT to cycle it by 10.
  */
 
 #include "movement.h"