NAME

       owtap - Packet sniffer for the owserver protocol

SYNOPSIS

       owtap -p owtap-tcp-port -s owserver-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-connector 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, temperature, 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 individually 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 consistent interface. The goal is to
       provide  an easy set of tools for a software 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 correctness rather than speed.

   owserver
       owserver (1) is the backend component of the OWFS 1-wire bus control  system.   owserver  (1)  arbitrates
       access  to  the  bus from multiple client processes. The physical bus is usually connected to a serial or
       USB port, and other processes connect to owserver (1) over network sockets (tcp port).

       Frontend clients include a filesystem representation: owfs (1) , and a webserver:  owhttpd  (1).   Direct
       language bindings are also available, e.g: owperl (3).

       There  are  also  many  light-weight clients that can only talk to owserver (1) and not to the 1-Wire bus
       directly. They include shell and multiple language modules (perl, Visual Basic, python,...)

   owserver protocol
       All the owserver (1) clients use the owserver protocol for communication. The owserver protocol is a well
       documented tcp/ip client/server protocol. Assigned the "well known port" default of 4304.

   owtap
       owtap  (1)  is  interposed  between  owserver  (1) and clients, to display and help resolve communication
       problems. Network communication is forwarded in both directions, but a visual display  is  also  created,
       with statistics and "drill-down" of individual packets.

SPECIFIC OPTIONS

   -p
       TCP port or IPaddress:port for owtap
       Other OWFS programs will access owtap via this address. (e.g. owdir -s IP:port /)

   -s
       TCP port or IPaddress:port for owserver
       The tcp port (IP:port) for the "upstream" owserver.

EXAMPLE

       If owserver (1) is started:
       owserver -p 4304 -d /dev/ttyS0
       owserver on tcp port 4304 and connects to a physical 1-wire bus on a serial port.

       You can directly query owserver (1) with
       owdir -s 4304 /

       To see the protocol in action:
       owtap -s 4304 -p 3000
       owdir -p 3000 /

       In  this case owtap (1) is connecting to owserver (1) on the original port (4304) and offering a new port
       (3000) for clients.

PLATFOMS

       owtap (1) is a pure Tcl/TK program and will run wherever Tcl/TK is available (Windows, Macintosh,  Linux,
       Unix)

LINKS

   owserver protocol
       http://www.owfs.org/index.php?page=owserver-protocol

   Tcl/TK
       http://www.tcl.tk

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

AVAILABILITY

       http://www.owfs.org

AUTHOR

       Paul Alfille (paul.alfille@gmail.com)