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OWHTTPD(1)		      One-Wire File System		      OWHTTPD(1)

NAME
     owhttpd - Tiny webserver for 1-wire control

SYNOPSIS
     owhttpd [ -c config ] -d serialport | -u | -s [host:]port -p tcp-port

DESCRIPTION
   1-Wire
     1-wire is a wiring protocol and series of devices designed and manufactured
     by  Dallas Semiconductor, Inc. The bus is a low-power low-speed low-connec-
     tor scheme where the data line can also provide power.

     Each device is uniquely and unalterably numbered during manufacture.  There
     are a wide variety of devices, including memory, sensors (humidity, temper-
     ature,  voltage, contact, current), switches, timers and data loggers. More
     complex devices (like thermocouple sensors) can be built with  these  basic
     devices. There are also 1-wire devices that have encryption included.

     The  1-wire scheme uses a single bus master and multiple slaves on the same
     wire. The bus master initiates all communication. The slaves can  be  indi-
     vidually discovered and addressed using their unique ID.

     Bus masters come in a variety of configurations including serial, parallel,
     i2c, network or USB adapters.

   OWFS design
     OWFS  is  a  suite of programs that designed to make the 1-wire bus and its
     devices easily accessible. The underlying principle is to create a  virtual
     filesystem,  with	the  unique  ID  being the directory, and the individual
     properties of the device are represented as simple files that can	be  read
     and written.

     Details  of  the individual slave or master design are hidden behind a con-
     sistent interface. The goal is to provide an easy set of tools for a  soft-
     ware  designer to create monitoring or control applications. There are some
     performance enhancements in the  implementation,  including  data	caching,
     parallel  access  to  bus masters, and aggregation of device communication.
     Still the fundamental goal has been ease of use, flexibility  and	correct-
     ness rather than speed.

   owhttpd
     owhttpd (1) is a small webserver that shows the Dallas/Maxim 1-Wire bus at-
     tached  to  a  serial  port. The main view shows the devices found, You can
     then navigate to individual devices, and view/alter their properties.

     owhttpd (1) uses the same naming convention as owfs (1)  ,  where	the  URL
     corresponds to the filename.

     The web server is a modified version of chttpd by Greg Olszewski. It serves
     no  files	from  the disk, only virtual files from the 1-wire bus. Security
     should therefore be good. Only the 1-wire bus is at risk.

SPECIFIC OPTIONS
   -p portnum
     Sets  the	tcp  port  the	web  server  runs  on.	Access	with   the   URL
     http://servernameoripaddress:portnum

     If  no  port  is  specified, an ephemeral port is selected by the operating
     system. Use zeroconf (Bonjour) to discover the assigned port.

Device Options (1-wire Bus Master)
     These options specify the device (bus master) connecting  the  computer  to
     the  1-wire bus. The 1-wire slaves are connected to the 1-wire bus, and the
     bus master connects to a port on the computer and controls the 1-wire  bus.
     The  bus  master is either an actual physical device, the kernel w1 module,
     or an owserver (1).

     At least one device option is required. There is no default. More than  one
     device can be listed, and all will be used. (A logical union unless you ex-
     plore the /bus.n/ directories.)

     Linux  and  BSD  enforce  a  security policy restricting access to hardware
     ports. You must have sufficient rights to access the given port  or  access
     will silently fail.

* Serial devices
     port  specifies  a serial port, e.g.  /dev/ttyS0 or an USB port accessed as
     serial port, e.g. /dev/ttyUSB0

     If OWFS was built with libftdi support, you may be able to  use  the  ftdi:
     prefix in any of the options as port to address a FTDI-based USB device.
     For details, see the FTDI ADDRESSING section.

     -d port | --device=port (DS2480B)
	    DS2480B-based bus master (like the DS9097U or an adapter of the LINK
	    family in emulation mode). If the adapter doesn't respond, a passive
	    type (DS9907E or diode/resistor) circuit will be assumed.

     --serial_flextime | --serial_regulartime (DS2480B)
	    Changes details of bus timing (see DS2480B datasheet). Some devices,
	    like the Swart LCD cannot work with flextime.

     --baud=1200|9600|19200|38400|57600|115200 (DS2480B,LINK,HA5)
	    Sets  the  initial	serial port communication speed for all bus mas-
	    ters. Not all serial devices support all speeds. You can change  the
	    individual	bus  master  speed  for  a device of the LINK family and
	    DS2880B in the interface/settings directory. The HA5 speed is set in
	    hardware, so the command line baud rate should match that rate.
	    Usually the default settings (9600 for a device of the  LINK  family
	    and  DS2480B  )  and  115200  for  the HA5 are sane and shouldn't be
	    changed.

     --straight_polarity  | --reverse_polarity (DS2480B)
	    Reverse polarity of the DS2480B output transistors? Not  needed  for
	    the DS9097U, but required for some other designs.

     --link=port (LINK)
	    iButtonLink  LINK adapter (all versions) in non-emulation mode. Uses
	    an ascii protocol over serial.
	    This supports the simplified ftdi:<serial number> addressing scheme.

     --ha7e=port (HA7E)
	    Embedded Data Systems HA7E adapter ( and  HA7S  )  in  native  ascii
	    mode.

     --ha5=port | --ha5=port:a | --ha5=port:acg (HA5)
	    Embedded  Data Systems HA5 mutidrop adapter in native ascii mode. Up
	    to 26 adapters can share the same port, each with an  assigned  let-
	    ter. If no letter specified, the program will scan for the first re-
	    sponse (which may be slow).

     --checksum | --no_checksum (HA5)
	    Turn  on (default) or off the checksum feature of the HA5 communica-
	    tion.

     --passive=port | --ha2=port | --ha3=port | --ha4b=port (Passive)
	    Passive 1-wire adapters. Powered off the serial port and using  pas-
	    sive electrical components (resitors and diodes).

     --8bit | --6bit (Passive)
	    Synthesize the 1-wire waveforme using a 6-bit (default) serial word,
	    or 8-bit word. Not all UART devices support 6 bit operation.

     --timeout_serial=5
	    Timeout  (in  seconds)  for  all serial communications. 5 second de-
	    fault. Can be altered dynamically under /settings/timeout/serial

* USB devices
     The only supported true USB bus masters are based on the DS2490  chip.  The
     most  common is the DS9490R which has an included 1-wire ID slave with fam-
     ily code 81.

     There are also bus masters based on the serial chip with a  USB  to  serial
     conversion built in. These are supported by the serial bus master protocol.

     -u | --usb
	    DS2490 based bus master (like the DS9490R).

     -u2 | --usb=2
	    Use  the  second  USB bus master. (The order isn't predicatble, how-
	    ever, since the operating system does not consistently order USB de-
	    vices).

     -uall | --usb=ALL
	    Use all the USB devices.

     --usb_flextime | --usb_regulartime
	    Changes the details of 1-wire waveform timing  for	certain  network
	    configurations.

     --altusb
	    Willy Robion's alternative USB timing.

     --timeout_usb=5
	    Timeout  for USB communications. This has a 5 second default and can
	    be changed dynamically under /settings/timeout/usb

* I2C devices
     I2C is  2 wire protocol used for chip-to-chip communication. The  bus  mas-
     ters:  DS2482-100, DS2482-101 and DS2482-800 can specify (via pin voltages)
     a subset of addresses on the i2c bus. Those choices are

     i2c_address

     0,1,2,3
	    0x18,0x19,0x1A,0x1B

     4,5,6,7
	    0x1C,0x1D,0x1E,0x1F (DS2482-800 only)

     port for i2c masters have the form /dev/i2c-0, /dev/i2c-1, ...

     -d port | --device=port
	    This simple form only permits a specific port and the  first  avail-
	    able i2c_address

     --i2c=port | --i2c=port:i2c_address | --i2c=port:ALL
	    Specific i2c port and the i2c_address is either the first, specific,
	    or all or them. The i2c_address is 0,1,2,...

     --i2c | --i2c=: | --i2c=ALL:ALL
	    Search  the  available i2c buses for either the first, the first, or
	    every i2c adapter.

     The DS2482-800 masters 8 1-wire buses and so will	generate  8  /bus.n  en-
     tries.

* Network devices
     These bus masters communicate via the tcp/ip network protocol and so can be
     located  anywhere	on  the  network.   The  network_address  is of the form
     tcp_address:port

     E.g. 192.168.0.1:3000 or localhost:3000

     --link=network_address
	    LinkHubE network LINK adapter by iButtonLink

     --ha7net=network_address | --ha7net
	    HA7Net network 1-wire adapter with specified tcp address or  discov-
	    ered by udp multicast. By Embedded Data Systems
	    --timeout_ha7=60 specific timeout for HA7Net communications (60 sec-
	    ond default).

     --etherweather=network_address
	    Etherweather adapter

     -s network_address | --server=network_address
	    Location  of  an  owserver (1) program that talks to the 1-wire bus.
	    The default port is 4304.

     --timeout_network=5
	    Timeout for network bus master communications. This has a  1  second
	    default  and can be changed dynamically under /settings/timeout/net-
	    work

* Simulated devices
     Used for testing and development. No actual hardware is needed. Useful  for
     separating the hardware development from the rest of the software design.

     devices
	    is	a  list  of comma-separated 1-wire devices in the following for-
	    mats. Note that a valid CRC8 code is created automatically.

     10,05,21
	    Hexadecimal family codes (the DS18S20, DS2405 and DS1921 in this ex-
	    ample).

     10.12AB23431211
	    A more complete hexadecimal unique address. Useful	when  an  actual
	    hardware device should be simulated.

     DS2408,DS2489
	    The  1-wire  device  name. (Full ID cannot be speciifed in this for-
	    mat).

     --fake=devices
	    Random address and random values for each read.  The  device  ID  is
	    also random (unless specified).

     --temperature_low=12 --temperature_high=44
	    Specify  the  temperature  limits  for  the fake adapter simulation.
	    These should be in the same temperature scale that is  specified  in
	    the  command  line.  It is possible to change the limits dynamically
	    for each adapter under /bus.x/interface/settings/simulated/[tempera-
	    ture_low|temperature_high]

     --tester=devices
	    Predictable address and predictable values for each read.  (See  the
	    website for the algorhythm).

* w1 kernel module
     This a linux-specific option for using the operating system's access to bus
     masters.  Root  access  is  required  and	the  implementation was still in
     progress as of owfs v2.7p12 and linux 2.6.30.

     Bus masters are recognized and added dynamically. Details of  the	physical
     bus  master  are  not  accessible, bu they include USB, i2c and a number of
     GPIO designs on embedded boards.

     Access is restrict to superuser due to the netlink broadcast  protocol  em-
     ployed by w1. Multitasking must be configured (threads) on the compilation.

     --w1   Use the linux kernel w1 virtual bus master.

     --timeout_w1=10
	    Timeout  for w1 netlink communications. This has a 10 second default
	    and can be changed dynamically under /settings/timeout/w1

FTDI ADDRESSING
     FTDI is a brand of USB-to-serial chips which are very common. If your  ser-
     ial device is connected via a USB serial dongle based on a FTDI chip, or if
     your  adapter uses a built-in FTDI USB chip (for example, the LinkUSB), you
     can use this FTDI addressing.

     The main benefit with this mode of access is that we can decrease the  com-
     munication  delay,  yielding  twice  as  fast  1-Wire communication in many
     cases.

     The following values for port can be used to identify a specific FTDI  port
     in several of the serial devices options.
     Note  that  this  requires  that  OWFS is built with libftdi support, which
     might not be the case in standard repositories.

     ftdi:d:<device-node>
	    path of bus and device-node (e.g. "003/001") within usb device  tree
	    (usually at /proc/bus/usb/ or /dev/bus/usb/)

     ftdi:i:<vendor>:<product>
	    first  device  with given vendor and product id, ids can be decimal,
	    octal (preceded by "0") or hex (preceded by "0x")

     ftdi:i:<vendor>:<product>:<index>
	    as above with index being the number of the device (starting with 0)
	    if there are more than one

     ftdi:s:<vendor>:<product>:<serial number>
	    the device with given vendor id, product id and serial number string

     The above formats are parsed fully by libftdi (minus the ftdi: prefix).

   Simplified device serial-only support
     An additional format is supported, for certain bus types. This only  speci-
     fies the USB serial number.

     ftdi:<serial number>
	    Identifies	a FTDI device by serial number only.  Currently, this is
	    only valid for the VID/PID found on the LinkUSB (i.e. --link).  Note
	    that those VID/PID's are the default for any FT232R device,  and  in
	    no way exclusive to LinkUSB.

   Permsissions
     In  order	to run owserver (1) without root privileges - as you should, you
     must have sufficient permissions to the raw USB node your adapter	is  con-
     nected to e.g. "003/001" (usually at /proc/bus/usb/ or /dev/bus/usb/).

     An easy way to achieve this would be using chown (1):

     sudo chown :<your user> /dev/bus/usb/003/001
	    changes  the group of the raw USB node "003/001" from default "root"
	    to "<your user>"

     You can also write a udev (1) rule for your adapter:

     SUBSYSTEM=="usb", DRIVER=="usb", ATTR{idVendor}=="0403", ATTR{idProd-
     uct}=="6001", ATTR{serial}=="AK0048A0", GROUP="owsrv"
	    saved    as    a	file	 e.g.	  "10-FTDI-LinkUSB.rules"     in
	    "/etc/udev/rules.d/",  this rule will automate the process of chang-
	    ing the group to "owsrv" of the raw USB  node  the	LinkUSB  adapter
	    with S/N:AK0048A0 is connected to.

   Serial USB node
     Communication in FTDI mode accesses the RAW USB node and NOT the serial USB
     node your OS might have created automatically e.g. /dev/ttyUSB0.
     As a side effect, if existing, the serial USB node e.g. /dev/ttyUSB0 is re-
     moved  on	successful  starting of owserver (1). After it's termination un-
     and re-plugging the adapter, or un- and reloading of  the	module	ftdi_sio
     will recreate the serial USB node.

   Finding FTDI related information on your USB adapter
     owusbprobe  is  THE tool to find the information needed for direct FTDI ad-
     dressing
     However this tool might not yet be packaged in your version.  Alternatively
     you  can  also use lsusb to find the usb node your adapter is connected to,
     and then use lsusb again on this very node:

     sudo lsusb -D /path/to/your/raw/USB/device/node  |egrep "idVendor|idProd-
     uct|iSerial"
	    sudo is necessary to get the value of iSerial field, if the  permis-
	    sions are still unchanged

   Examples FTDI addressing
     owserver -d ftdi:s:0x0403:0x6001:A800bXHr
	    starts  owserver with a LinkUSB (VID:0x0403,PID:0x6001,S/N:A800bXHr)
	    as bus master in DS2480B-based emulation mode with direct  FTDI  ac-
	    cess

     owserver --link=ftdi:A800bXHr
	    starts  owserver with a LinkUSB (S/N:A800bXHr) as bus master identi-
	    fied by serial number only in native mode with direct FTDI access

TEMPERATURE SCALE OPTIONS
   -C --Celsius
   -F --Fahrenheit
   -K --Kelvin
   -R --Rankine
     Temperature scale used for data output. Celsius is the default.

     Can also be changed within the program at /settings/units/temperature_scale

PRESSURE SCALE OPTIONS
   --mbar (default)
   --atm
   --mmHg
   --inHg
   --psi
   --Pa
     Pressure scale used for data output. Millibar is the default.

     Can also be changed within the program at /settings/units/pressure_scale

FORMAT OPTIONS
     Choose the representation of the 1-wire unique identifiers. OWFS uses these
     identifiers as unique directory names.

     Although several display formats are selectable, all must be in  family-id-
     crc8  form, unlike some other programs and the labelling on iButtons, which
     are crc8-id-family form.

   -f --format="f[.]i[[.]c]"
     Display format for the 1-wire devices. Each device  has  a  8byte	address,
     consisting of:

     f	    family code, 1 byte

     i	    ID number, 6 bytes

     c	    CRC checksum, 1 byte

     Possible  formats are f.i (default, 01.A1B2C3D4E5F6), fi fic f.ic f.i.c and
     fi.c

     All formats are accepted as input, but the output will be in the  specified
     format.

     The  address  elements  can be retrieved from a device entry in owfs by the
     family, id and crc8 properties, and as a whole with address.  The	reversed
     id and address can be retrieved as r_id and r_address.

JOB CONTROL OPTIONS
   -r --readonly
   -w --write
     Do  we  allow  writing to the 1-wire bus (writing memory, setting switches,
     limits, PIOs)? The write option is available for  symmetry,  it's	the  de-
     fault.

   -P --pid-file filename
     Places  the  PID  -- process ID of owfs into the specified filename. Useful
     for startup scripts control.

   --background | --foreground
     Whether the program releases the console and runs in the  background  after
     evaluating command line options.  background is the default.

   --error_print=0|1|2|3
     =0     default mixed destination: stderr foreground / syslog background

     =1     syslog only

     =2     stderr only

     =3     /dev/null (quiet mode).

   --error_level=0..9
     =0     default errors only

     =1     connections/disconnections

     =2     all high level calls

     =3     data summary for each call

     =4     details level

     >4     debugging chaff

     --error_level=9 produces a lot of output

CONFIGURATION FILE
   -c file | --configuration file
     Name of an owfs (5) configuration file with more command line parameters

HELP OPTIONS
     See also this man page and the web site http://www.owfs.org

   -h --help=[device|cache|program|job|temperature]
     Shows basic summary of options.

     device
	    1-wire bus master options

     cache  cache and communication size and timing

     program
	    mountpoint or TCP server settings

     job    control and debugging options

     temperature
	    Unique ID display format and temperature scale

   -V --version
     Version of this program and related libraries.

TIME OPTIONS
     Timeouts  for  the  bus  masters  were previously listed in Device options.
     Timeouts for the cache affect the time that data stays in	memory.  Default
     values are shown.

   --timeout_volatile=15
     Seconds until a volatile property expires in the cache. Volatile properties
     are those (like temperature) that change on their own.

     Can be changed dynamically at /settings/timeout/volatile

   --timeout_stable=300
     Seconds until a stable property expires in the cache. Stable properties are
     those  that shouldn't change unless explicitly changed. Memory contents for
     example.

     Can be changed dynamically at /settings/timeout/stable

   --timeout_directory=60
     Seconds until a directory listing expires in the cache. Directory lists are
     the 1-wire devices found on the bus.

     Can be changed dynamically at /settings/timeout/directory

   --timeout_presence=120
     Seconds until the presence and bus location of a 1-wire device  expires  in
     the cache.

     Can be changed dynamically at /settings/timeout/presence

     There are also timeouts for specific program responses:

   --timeout_server=5
     Seconds until the expected response from the owserver (1) is deemed tardy.

     Can be changed dynamically at /settings/timeout/server

   --timeout_ftp=900
     Seconds that an ftp session is kept alive.

     Can be changed dynamically at /settings/timeout/ftp

EXAMPLE
     owhttpd -p 3001 -d /dev/ttyS0
	    Web server runs on tcp port 3001, serial adapter at ttyS0

     owhttpd -p 3001 -s littlehost:4304 --error_level=3
	    Web server on port 3001, from owserver process on host "littlehost",
	    extensive error messages.

     owhttpd -p 3001 -u -u2 -r
	    Read-only web server on port 3001, using two usb adapters.

AVAILABILITY
     http://www.owfs.org

SEE ALSO
   Programs
     owfs  (1)	owhttpd (1) owftpd (1) owserver (1) owdir (1) owread (1) owwrite
     (1) owpresent (1) owtap (1)

   Configuration and testing
     owfs (5) owtap (1) owmon (1)

   Language bindings
     owtcl (3) owperl (3) owcapi (3)

   Clocks
     DS1427 (3) DS1904(3) DS1994 (3) DS2404 (3) DS2404S (3)  DS2415  (3)  DS2417
     (3)

   ID
     DS2401 (3) DS2411 (3) DS1990A (3)

   Memory
     DS1982  (3)  DS1985  (3) DS1986 (3) DS1991 (3) DS1992 (3) DS1993 (3) DS1995
     (3) DS1996 (3) DS2430A (3) DS2431 (3) DS2433  (3)	DS2502	(3)  DS2506  (3)
     DS28E04 (3) DS28EC20 (3)

   Switches
     DS2405 (3) DS2406 (3) DS2408 (3) DS2409 (3) DS2413 (3) DS28EA00 (3)

   Temperature
     DS1822  (3) DS1825 (3) DS1820 (3) DS18B20 (3) DS18S20 (3) DS1920 (3) DS1921
     (3) DS1821 (3) DS28EA00 (3) DS28E04 (3)

   Humidity
     DS1922 (3)

   Voltage
     DS2450 (3)

   Resistance
     DS2890 (3)

   Multifunction (current, voltage, temperature)
     DS2436 (3) DS2437 (3) DS2438 (3) DS2751 (3) DS2755 (3)  DS2756  (3)  DS2760
     (3) DS2770 (3) DS2780 (3) DS2781 (3) DS2788 (3) DS2784 (3)

   Counter
     DS2423 (3)

   LCD Screen
     LCD (3) DS2408 (3)

   Crypto
     DS1977 (3)

   Pressure
     DS2406 (3) -- TAI8570

AUTHOR
     Paul Alfille (paul.alfille@gmail.com)

OWFS Manpage			      2004			      OWHTTPD(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=owhttpd&sektion=1&manpath=FreeBSD+Ports+15.1.quarterly>

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