Based on kernel version 4.16.1. Page generated on 2018-04-09 11:53 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 via sysfs attributes. 46 47 Notes: 48 * The regulator supply name is set to "vcc". 49 * If a CRC validation fails, a soft reset command is sent, which resets 50 status register to its hardware default value, but the driver will try to 51 restore the previous device configuration. 52 53 Platform data 54 ------------- 55 56 * checksum: 57 set it to true to enable CRC validation of the readings (default to false). 58 * no_otp_reload: 59 flag to indicate not to reload from OTP (default to false). 60 * low_resolution: 61 flag to indicate the temp/humidity resolution to use (default to false). 62 63 Sysfs interface 64 --------------- 65 66 * temp1_input: temperature input 67 * humidity1_input: humidity input 68 * heater_enable: write 1 in this attribute to enable the on-chip heater, 69 0 to disable it. Be careful not to enable the heater 70 for too long. 71 * temp1_fault: if 1, this means that the voltage is low (below 2.47V) and 72 measurement may be invalid. 73 * humidity1_fault: same as temp1_fault.