About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Documentation / hwmon / sht15




Custom Search

Based on kernel version 3.16. Page generated on 2014-08-06 21:39 EST.

1	Kernel driver sht15
2	===================
3	
4	Authors:
5	  * Wouter Horre
6	  * Jonathan Cameron
7	  * Vivien Didelot <vivien.didelot@savoirfairelinux.com>
8	  * Jerome Oufella <jerome.oufella@savoirfairelinux.com>
9	
10	Supported chips:
11	  * Sensirion SHT10
12	    Prefix: 'sht10'
13	
14	  * Sensirion SHT11
15	    Prefix: 'sht11'
16	
17	  * Sensirion SHT15
18	    Prefix: 'sht15'
19	
20	  * Sensirion SHT71
21	    Prefix: 'sht71'
22	
23	  * Sensirion SHT75
24	    Prefix: 'sht75'
25	
26	Datasheet: Publicly available at the Sensirion website
27	http://www.sensirion.ch/en/pdf/product_information/Datasheet-humidity-sensor-SHT1x.pdf
28	
29	Description
30	-----------
31	
32	The SHT10, SHT11, SHT15, SHT71, and SHT75 are humidity and temperature
33	sensors.
34	
35	The devices communicate using two GPIO lines.
36	
37	Supported resolutions for the measurements are 14 bits for temperature and 12
38	bits for humidity, or 12 bits for temperature and 8 bits for humidity.
39	
40	The humidity calibration coefficients are programmed into an OTP memory on the
41	chip. These coefficients are used to internally calibrate the signals from the
42	sensors. Disabling the reload of those coefficients allows saving 10ms for each
43	measurement and decrease power consumption, while losing on precision.
44	
45	Some options may be set directly in the sht15_platform_data structure
46	or via sysfs attributes.
47	
48	Notes:
49	  * The regulator supply name is set to "vcc".
50	  * If a CRC validation fails, a soft reset command is sent, which resets
51	    status register to its hardware default value, but the driver will try to
52	    restore the previous device configuration.
53	
54	Platform data
55	-------------
56	
57	* checksum:
58	  set it to true to enable CRC validation of the readings (default to false).
59	* no_otp_reload:
60	  flag to indicate not to reload from OTP (default to false).
61	* low_resolution:
62	  flag to indicate the temp/humidity resolution to use (default to false).
63	
64	Sysfs interface
65	---------------
66	
67	* temp1_input:     temperature input
68	* humidity1_input: humidity input
69	* heater_enable:   write 1 in this attribute to enable the on-chip heater,
70	                   0 to disable it. Be careful not to enable the heater
71	                   for too long.
72	* temp1_fault:     if 1, this means that the voltage is low (below 2.47V) and
73	                   measurement may be invalid.
74	* humidity1_fault: same as temp1_fault.
Hide Line Numbers
About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Information is copyright its respective author. All material is available from the Linux Kernel Source distributed under a GPL License. This page is provided as a free service by mjmwired.net.