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1What: /sys/bus/w1/devices/.../alarms2Date: May 20203Contact: Akira Shimahara <akira215corp@gmail.com>4Description:5 (RW) read or write TH and TL (Temperature High an Low) alarms.6 Values shall be space separated and in the device range7 (typical -55 degC to 125 degC), if not values will be trimmed8 to device min/max capabilities. Values are integer as they are9 stored in a 8bit register in the device. Lowest value is10 automatically put to TL. Once set, alarms could be search at11 master level, refer to Documentation/w1/w1-generic.rst for12 detailed information13Users: any user space application which wants to communicate with14 w1_term device15 16 17What: /sys/bus/w1/devices/.../eeprom_cmd18Date: May 202019Contact: Akira Shimahara <akira215corp@gmail.com>20Description:21 (WO) writing that file will either trigger a save of the22 device data to its embedded EEPROM, either restore data23 embedded in device EEPROM. Be aware that devices support24 limited EEPROM writing cycles (typical 50k)25 26 * 'save': save device RAM to EEPROM27 * 'restore': restore EEPROM data in device RAM28 29Users: any user space application which wants to communicate with30 w1_term device31 32 33What: /sys/bus/w1/devices/.../ext_power34Date: May 202035Contact: Akira Shimahara <akira215corp@gmail.com>36Description:37 (RO) return the power status by asking the device38 39 * '0': device parasite powered40 * '1': device externally powered41 * '-xx': xx is kernel error when reading power status42 43Users: any user space application which wants to communicate with44 w1_term device45 46 47What: /sys/bus/w1/devices/.../resolution48Date: May 202049Contact: Akira Shimahara <akira215corp@gmail.com>50Description:51 (RW) get or set the device resolution (on supported devices,52 if not, this entry is not present). Note that the resolution53 will be changed only in device RAM, so it will be cleared when54 power is lost. Trigger a 'save' to EEPROM command to keep55 values after power-on. Read or write are :56 57 * '9..14': device resolution in bit58 or resolution to set in bit59 * '-xx': xx is kernel error when reading the resolution60 * Anything else: do nothing61 62 Some DS18B20 clones are fixed in 12-bit resolution, so the63 actual resolution is read back from the chip and verified. Error64 is reported if the results differ.65Users: any user space application which wants to communicate with66 w1_term device67 68 69What: /sys/bus/w1/devices/.../temperature70Date: May 202071Contact: Akira Shimahara <akira215corp@gmail.com>72Description:73 (RO) return the temperature in 1/1000 degC.74 75 * If a bulk read has been triggered, it will directly76 return the temperature computed when the bulk read77 occurred, if available. If not yet available, nothing78 is returned (a debug kernel message is sent), you79 should retry later on.80 * If no bulk read has been triggered, it will trigger81 a conversion and send the result. Note that the82 conversion duration depend on the resolution (if83 device support this feature). It takes 94ms in 9bits84 resolution, 750ms for 12bits.85 86Users: any user space application which wants to communicate with87 w1_term device88 89 90What: /sys/bus/w1/devices/.../w1_slave91Date: May 202092Contact: Akira Shimahara <akira215corp@gmail.com>93Description:94 (RW) return the temperature in 1/1000 degC.95 *read*: return 2 lines with the hexa output data sent on the96 bus, return the CRC check and temperature in 1/1000 degC97 *write*:98 99 * '0' : save the 2 or 3 bytes to the device EEPROM100 (i.e. TH, TL and config register)101 * '9..14' : set the device resolution in RAM102 (if supported)103 * Anything else: do nothing104 105 refer to Documentation/w1/slaves/w1_therm.rst for detailed106 information.107Users: any user space application which wants to communicate with108 w1_term device109 110 111What: /sys/bus/w1/devices/w1_bus_masterXX/therm_bulk_read112Date: May 2020113Contact: Akira Shimahara <akira215corp@gmail.com>114Description:115 (RW) trigger a bulk read conversion. read the status116 117 *read*:118 * '-1':119 conversion in progress on at least 1 sensor120 * '1' :121 conversion complete but at least one sensor122 value has not been read yet123 * '0' :124 no bulk operation. Reading temperature will125 trigger a conversion on each device126 127 *write*:128 'trigger': trigger a bulk read on all supporting129 devices on the bus130 131 Note that if a bulk read is sent but one sensor is not read132 immediately, the next access to temperature on this device133 will return the temperature measured at the time of issue134 of the bulk read command (not the current temperature).135Users: any user space application which wants to communicate with136 w1_term device137 138 139What: /sys/bus/w1/devices/.../conv_time140Date: July 2020141Contact: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru>142Description:143 (RW) Get, set, or measure a temperature conversion time. The144 setting remains active until a resolution change. Then it is145 reset to default (datasheet) conversion time for a new146 resolution.147 148 *read*:149 Actual conversion time in milliseconds.150 151 *write*:152 * '0':153 Set the default conversion time from the datasheet.154 * '1':155 Measure and set the conversion time. Make a single156 temperature conversion, measure an actual value.157 Increase it by 20% for temperature range. A new158 conversion time can be obtained by reading this159 same attribute.160 * other positive value:161 Set the conversion time in milliseconds.162 163Users: An application using the w1_term device164 165 166What: /sys/bus/w1/devices/.../features167Date: July 2020168Contact: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru>169Description:170 (RW) Control optional driver settings.171 Bit masks to read/write (bitwise OR):172 173 == ============================================================174 1 Enable check for conversion success. If byte 6 of175 scratchpad memory is 0xC after conversion, and176 temperature reads 85.00 (powerup value) or 127.94177 (insufficient power) - return a conversion error.178 179 2 Enable poll for conversion completion. Generate read cycles180 after the conversion start and wait for 1's. In parasite181 power mode this feature is not available.182 == ============================================================183 184 *read*:185 Currently selected features.186 187 *write*:188 Select features.189 190Users: An application using the w1_term device191