- * Reads the ADC pin connected to the LiPoly battery. The connection is made
- * via a resistor divider where the battery voltage is 3x that read by the ADC.
- * Therefore, BattV = ADC / 4096 * 1.5 * 3.
+ * Reads the ADC pin connected to the Davis Instruments anemometer. The
+ * connection is made via a resistor divider. The voltage seen by the ADC
+ * is related to VREF, the maximum voltage presented to the ADC.
+ * 0V or VREF means North
+ * VREF*1/4 means East
+ * VREF*2/4 means South
+ * VREF*3/4 means West
+ *
+ * We assume a 12-bit ADC, so VREF reads as 4095 and 0V reads as 0.