Merge pull request #22 from stonehippo/proximity_frequency_read_fix

Fix proximity read frequency

Author: ladyada

adafruit_vcnl4010.py

@@ -55,6 +55,17 @@
 _VCNL4010_AMBIENT_LUX_SCALE = 0.25  # Lux value per 16-bit result value.
 
 # User-facing constants:
+# Number of proximity measuremenrs per second
+SAMPLERATE_1_95 = 0
+SAMPLERATE_3_90625 = 1
+SAMPLERATE_7_8125 = 2
+SAMPLERATE_16_625 = 3
+SAMPLERATE_31_25 = 4
+SAMPLERATE_62_5 = 5
+SAMPLERATE_125 = 6
+SAMPLERATE_250 = 7
+
+# Proximity modulator timing
 FREQUENCY_3M125 = 3
 FREQUENCY_1M5625 = 2
 FREQUENCY_781K25 = 1
@@ -113,6 +124,7 @@ def __init__(self, i2c, address=_VCNL4010_I2CADDR_DEFAULT):
         if (revision & 0xF0) != 0x20:
             raise RuntimeError("Failed to find VCNL4010, check wiring!")
         self.led_current = 20
+        self.samplerate = SAMPLERATE_1_95
         self.frequency = FREQUENCY_390K625
         self._write_u8(_VCNL4010_INTCONTROL, 0x08)
 
@@ -153,8 +165,8 @@ def led_current(self, val):
 
     @property
     def led_current_mA(self):
-        """The current of the LED in milli-amps.  The value here is
-        specified in a milliamps from 0-200.  Note that this value will be
+        """The current of the LED in milliamps.  The value here is
+        specified in milliamps from 0-200.  Note that this value will be
         quantized down to a smaller less-accurate value as the chip only
         supports current changes in 10mA increments, i.e. a value of 123 mA will
         actually use 120 mA.  See the datasheet for how the LED current impacts
@@ -167,18 +179,44 @@ def led_current_mA(self):
     def led_current_mA(self, val):
         self.led_current = val // 10
 
+    @property
+    def samplerate(self):
+        """
+        The frequency of proximity measurements per second.  Must be a value of:
+
+        - SAMPLERATE_1_95: 1.95 measurements/sec (default)
+        - SAMPLERATE_3_90625: 3.90625 measurements/sec
+        - SAMPLERATE_7_8125: 7.8125 measurements/sec
+        - SAMPLERATE_16_625: 16.625 measurements/sec
+        - SAMPLERATE_31_25: 31.25 measurements/sec
+        - SAMPLERATE_62_5: 62.5 measurements/sec
+        - SAMPLERATE_125: 125 measurements/sec
+        - SAMPLERATE_250: 250 measurements/sec
+
+        See the datasheet for how frequency changes the power consumption and
+        proximity detection accuracy.
+        """
+        return self._read_u8(_VCNL4010_PROXRATE)
+
+    @samplerate.setter
+    def samplerate(self, val):
+        assert 0 <= val <= 7
+        self._write_u8(_VCNL4010_PROXRATE, val)
+
     @property
     def frequency(self):
         """
-        The frequency of proximity measurements.  Must be a value of:
+        Proximity modulator timimg. This is the frequency of the IR square
+        wave used for the proximity measurement.
+
+                Must be a value of:
 
         - FREQUENCY_3M125: 3.125 Mhz
         - FREQUENCY_1M5625: 1.5625 Mhz
         - FREQUENCY_781K25: 781.25 Khz
         - FREQUENCY_390K625: 390.625 Khz (default)
 
-        See the datasheet for how frequency changes the proximity detection
-        accuracy.
+        The datasheet recommended leaving this at the default.
         """
         return (self._read_u8(_VCNL4010_MODTIMING) >> 3) & 0x03