sht1x: Initial implementation

This driver was developed with a DFRobot SHT10 Temperature and Humidity
sensor.  This driver should work on all SHT1X devices.

It requires a 10K pull-up resistor connected to the data pin.
The sensor can be run at differing voltages from 2.5v to 5v.

Signed-off-by: Jon Trulson <jtrulson@ics.com>

examples/python/sht1x.py

@@ -0,0 +1,53 @@
+#!/usr/bin/python
+# Author: Jon Trulson <jtrulson@ics.com>
+# Copyright (c) 2016 Intel Corporation.
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+import time, sys, signal, atexit
+import pyupm_sht1x as sensorObj
+
+# Instantiate a SHT1X sensor using D2 as the clock, and D3 as the
+# data pin.
+sensor = sensorObj.SHT1X(2, 3)
+
+## Exit handlers ##
+# This function stops python from printing a stacktrace when you hit control-C
+def SIGINTHandler(signum, frame):
+	raise SystemExit
+
+# This function lets you run code on exit
+def exitHandler():
+	print "Exiting"
+	sys.exit(0)
+
+# Register exit handlers
+atexit.register(exitHandler)
+signal.signal(signal.SIGINT, SIGINTHandler)
+
+# Every 2 seconds, update and print values
+while (True):
+        sensor.update()
+
+        print "Temperature:", sensor.getTemperature(), "C"
+        print "Humidity:   ", sensor.getHumidity(), "RH"
+        print
+
+	time.sleep(2)