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       digitemp - program to read from temperature sensors.


       digitemp [options]


       DigiTemp  uses  the Dallas 1-wire bus to read temperatures from digital
       sensors attached to a serial port adapter. It handles initializing  the
       bus,  searching  for  attached  devices, reading devices and custom log
       strings. It suports the following temperature devices: DS1820, DS18S20,
       DS18B20, DS1822

       It  also  handles the DS2406 1-wire hub switches, and DS2422 and DS2423

       DigiTemp uses either the DS9097 passive serial  port  adapter,  or  the
       DS2480B based DS9097U adapter (recommended).


       At  least  1  action must be given, along with some optional arguments.
       Actions are one (and only on) of the -w -t -a -w options

       -h, -? Show summary of options.

       -v     Show verbose output.

       -i     Initialize .digitemprc file, search the bus  for  all  supported

       -w     Walk the full device tree and display the serial number and type
              of all devices detected on the bus.

       -s /dev/ttyS0
              Set serial port to use. Make sure you have permission to  access
              this port.

       -l /var/log/temperature
              Send  output  to logfile, the output format is defined by the .B
              -o command

       -c digitemp.conf
              Set digitemp configuration file. The default is  .digitemprc  in
              the current directory.

       -r 1000
              Read  delay  in ms. This sets the amount of time to wait between
              sending the  temperature  conversion  command  and  reading  the
              result.  The  DS18S20  takes  about  750mS to do the temperature
              conversion. Default is 1000mS (1 sec).

       -t #   Read sensor number #, the # depends on the order of the  sensors
              in the .digitemprc file.

       -q     Quiet output, no copyright banner.

       -a     Read all sensors.

       -A     Treat DS2438 as A/D converter, output raw voltages

       -d 5   Delay between samples (in seconds).

       -n 50  Number of times to repeat the command.

       -O"counter format string"
              See Counter Format below.

       -o [1..3] ["output format string"]
              See Temperature Format below.

       -H"Humidity format string"
              See Humidity Format below.

Temperature Format

       The  temperature format can be either a numeric value, or a string. The
       numeric values select pre-configured output formats:

           1 = One line per sensor, time, C, F (default)
           2 = One line per sample, elapsed time, temperature in C
           3 = Same as #2, except temperature is in F

       #2 and #3 have the data seperated by tabs, suitable for import  into  a
       spreadsheet or other graphing software.

       The  format  string  uses  strftime  tokens  plus  5  special  ones for

       %s     for sensor #

       %C     for centigrade

       %F     for fahrenheit

       %R     to output the hex serial number

       %N     for seconds since Epoch.

       The case of the token is important! The default format string  is:  "%b
       %d  %H:%M:%S  Sensor  %s C: %.2C F: %.2F" which gives you an output of:
       May 24 21:25:43 Sensor 0 C: 23.66 F: 74.59

       The DS2438 sensor can be used for a variety of things.  It  includes  a
       temperature  sensor and A/D converter. DigiTemp defaults to using it as
       a humidity sensor. The raw voltages can be displayed by passing the  -A

       When  the  -o2  or  -o3  log  options  are  used  the attached DS2438’s
       temperatures will be output without the humidity.

Counter Format String

       The counter format string is similar, adding these tokens:

       %n     is  the  counter  #,  which  depends  on  its  position  in  the
              .digitemprc file

       %C     is the count in decimal.

Humidity Format String

       The Humidity format string is the same as the temperature format string
       with the addition of this format specifier:

       %h     is the humidity in 0-100%


       This manual page was written by Jesús Roncero <>,  for
       the  Debian project (but may be used by others). Modifications by Brian
       C. Lane <>


       DigiTemp updates can be found on the website.

                                   June 2005