humidity_sht

SHTxx, for Sensirion humidity and temperature sensors

Author Eur van Andel, eur@fiwihex.nl Copyright (c) 2008
Adapted-by
Compiler =2.4h

Description

The Sensirion SHT1x/SHT7x is a single chip relative humidity and
temperature multi sensor module comprising a calibrated digital output.
It comes in 5 flavors, with different accuracy and package style:
sensor   hum acc  temp acc    package
SHT10    4.5      0.5         SMD (LCC)
SHT11    3.0      0.4         SMD (LCC) 
SHT15    2.0      0.3         SMD (LCC) 
SHT71    3.0      0.4         4-pin single-in-line 
SHT75    1.8      0.3         4-pin single-in-line 
all consist of the same silicon: the less accurate models are sold cheaper.
My experience is mixed: I've seen some consistent +2C offset in temperature,
but good humidty measurements. The 4-pin package breaks when you touch it.
The SMD package has naked tracks underneath: you can't route under it!
If exposed to >95% RH for 10 minutes, these sensors will go beserk and need 
<60% RH for an hour to recover. You might try heating them. 
protocol is close to I2C, but not the same. Remember to pull up DATA.
0b0000_0011  starts temperature measurement
0b0000_0101  starts humidity measurement
device returns three bytes: MSB, LSB and CRC
higher functions don't do a CRC check


Sources

http://www.sensirion.com/en/01_humidity_sensors/00_humidity_sensors.htm


Dependencies

No dependency found



Summary

Global variables/contants

Procedures

Functions


API details

Global variables/contants

Procedures

Functions


Related samples

Here are the list of samples which use this library:

16f876a16f876a_sht.jal