Here's my Arduino library for the TI HDC1000 temperature and humidity sensor. It should work with the HDC1008 too but I haven't tested it.
More details about the library and my breakout board for the chip on my website http://b.truzzi.me/hdc1000-temperature-and-humidity-sensor-breakout-with-arduino-library/.
First, declare it:
HDC1000 mySensor;
Default address is 0x40 and the DRDYn pin is disabled. You can change your address by declaring your sensor like this:
HDC1000 mySensor(addr, DRDYn_pin);
Then, initialize it:
mySensor.begin();
Default options are set to enable both temperature and humidity readings, at 14-bit resolution, with the integrated heater on. You can change them by initializing your sensor like this:
mySensor.begin(mode, resolution, heater);
"mode" can be HDC1000_SINGLE_MEASUR, HDC1000_BOTH_TEMP_HUMI or HDC1000_RST.
"resolution" can be HDC1000_TEMP_HUMI_14BIT, HDC1000_TEMP_11BIT, HDC1000_HUMI_11BIT, HDC1000_HUMI_8BIT.
"heater" can be HDC1000_HEAT_ON or HDC1000_HEAT_OFF.
You can read temperature and humidity by using the following commands:
double temperature = mySensor.getTemp();
in Celsius degrees.
double humidity = mySensor.getHumi();
in %
You can also access raw values from the sensor:
uint16_t temp = mySensor.getRawTemp();
uint16_t humi = mySensor.getRawHumi();
The following code returns '1' if the battery voltage is <2.8V, '0' otherwise.
boolean isDead = mySensor.battery();
This returns the 16-bit value of the internal configuration register (0x02): the last 8 bits are always zero and leading zeros are not displayed.
uint16_t config = mySensor.readConfig();
Happy making!