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Based on kernel version 4.16.1. Page generated on 2018-04-09 11:53 EST.

1	Kernel driver sht3x
2	===================
4	Supported chips:
5	  * Sensirion SHT3x-DIS
6	    Prefix: 'sht3x'
7	    Addresses scanned: none
8	    Datasheet: http://www.sensirion.com/fileadmin/user_upload/customers/sensirion/Dokumente/Humidity/Sensirion_Humidity_Datasheet_SHT3x_DIS.pdf
10	Author:
11	  David Frey <david.frey@sensirion.com>
12	  Pascal Sachs <pascal.sachs@sensirion.com>
14	Description
15	-----------
17	This driver implements support for the Sensirion SHT3x-DIS chip, a humidity
18	and temperature sensor. Temperature is measured in degrees celsius, relative
19	humidity is expressed as a percentage. In the sysfs interface, all values are
20	scaled by 1000, i.e. the value for 31.5 degrees celsius is 31500.
22	The device communicates with the I2C protocol. Sensors can have the I2C
23	addresses 0x44 or 0x45, depending on the wiring. See
24	Documentation/i2c/instantiating-devices for methods to instantiate the device.
26	There are two options configurable by means of sht3x_platform_data:
27	1. blocking (pull the I2C clock line down while performing the measurement) or
28	   non-blocking mode. Blocking mode will guarantee the fastest result but
29	   the I2C bus will be busy during that time. By default, non-blocking mode
30	   is used. Make sure clock-stretching works properly on your device if you
31	   want to use blocking mode.
32	2. high or low accuracy. High accuracy is used by default and using it is
33	   strongly recommended.
35	The sht3x sensor supports a single shot mode as well as 5 periodic measure
36	modes, which can be controlled with the update_interval sysfs interface.
37	The allowed update_interval in milliseconds are as follows:
38	  *     0   single shot mode
39	  *  2000   0.5 Hz periodic measurement
40	  *  1000   1   Hz periodic measurement
41	  *   500   2   Hz periodic measurement
42	  *   250   4   Hz periodic measurement
43	  *   100  10   Hz periodic measurement
45	In the periodic measure mode, the sensor automatically triggers a measurement
46	with the configured update interval on the chip. When a temperature or humidity
47	reading exceeds the configured limits, the alert attribute is set to 1 and
48	the alert pin on the sensor is set to high.
49	When the temperature and humidity readings move back between the hysteresis
50	values, the alert bit is set to 0 and the alert pin on the sensor is set to
51	low.
53	sysfs-Interface
54	---------------
56	temp1_input:        temperature input
57	humidity1_input:    humidity input
58	temp1_max:          temperature max value
59	temp1_max_hyst:     temperature hysteresis value for max limit
60	humidity1_max:      humidity max value
61	humidity1_max_hyst: humidity hysteresis value for max limit
62	temp1_min:          temperature min value
63	temp1_min_hyst:     temperature hysteresis value for min limit
64	humidity1_min:      humidity min value
65	humidity1_min_hyst: humidity hysteresis value for min limit
66	temp1_alarm:        alarm flag is set to 1 if the temperature is outside the
67	                    configured limits. Alarm only works in periodic measure mode
68	humidity1_alarm:    alarm flag is set to 1 if the humidity is outside the
69	                    configured limits. Alarm only works in periodic measure mode
70	heater_enable:      heater enable, heating element removes excess humidity from
71	                    sensor
72	                        0: turned off
73	                        1: turned on
74	update_interval:    update interval, 0 for single shot, interval in msec
75	                    for periodic measurement. If the interval is not supported
76	                    by the sensor, the next faster interval is chosen
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