owtcl - Man Page

OWFS library access commands for Tcl

Synopsis

package require ow

ow option ?arg ...?

::OW::init interface ?interface ...? ?arg ...? ::OW::finish ::OW::isconnect ::OW::get ?path? ?arg ...? ::OW::put path ?value? ::OW::isdirectory path ::OW::isdir path ::OW::exists path

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.

owtcl

owtcl (3) is a Tcl extension that provides an interface to OWFS. The underlying interface to the 1-wire bus is identical to owfs (1) (filesystem view) and owhttpd (1) web server interface. Only the top layer has been modified to return native Tcl data.

Commands

Performs one of several operations, depending on option. The legal options (which may be abbreviated) are:

ow open arg ...: Connect to 1-wire adapter or owserver. arg ... defines a way of connection to the 1-wire bus.
The full set of initialization args is extensive. They correspond roughly to the command line args of owfs (1) owhttpd (1) and owftpd (1)
ow close: Close connection to 1-wire bus or owserver.
ow version ?-list?: Return version of the owtcl and owlib/
ow opened: Return 1 if connected to 1-wire adapter or owserver, otherwise 0.
ow error level value: Set debug options. See owfs (5)
ow error print value: Set debug options. See owfs (5)
ow get path ?-list?: Returns contents of OWFS directory as the list if path contains name OWFS directory. If path is name of OWFS file, returns of contents of this file. For files *.ALL returns a values list.
ow put path value: Puts value in OWFS file indicated in path. For files *.ALL use a value list.
ow isdirectory path: If path is the directory return 1. Otherwise return 0.
ow isdir path: Synonym of ow isdirectory
ow set path: Creates a new ow-like command with root in the path. A new command allows options get, put, isdirectory, isdir and set.

Low-Level Commands

The following low-level commands are possible:

::OW::init interface ?interface ...? ?arg ...?: Connect to 1-wire adapter or owserver. interface and arg ... defines a way of connection to the 1-wire bus.
The full set of initialization options is extensive. They correspond roughly to the command line options of ,B owfs (1) owhttpd (1) and owftpd (1)
::OW::finish: Close connection to 1-wire bus or owserver.
::OW::isconnect: Return 1 if connected to 1-wire adapter or owserver, otherwise 0.
::OW::get ?path? ?-list?: Returns contents of OWFS directory as the list if path contains name OWFS directory. If path is name of OWFS file, returns of contents of this file. For files *.ALL returns a values list. If path is not defined, contents of root OWFS directory come back.
::OW::put path ?value?: Puts value in OWFS file indicated in path. For files *.ALL use a value list. If /fIvalue is not defined, puts a empty string.
::OW::isdirectory path: If path is the directory - return 1. Otherwise return 0.
::OW::isdir path: Synonym of ::OW::isdirectory
::OW::exists path: If path is exists - return 1. Otherwise return 0.

Example

package require ow

ow open -d /dev/ttyS0 -t 60

set save_templow [ow get /28.86BF80000000/templow]
ow put /28.86BF80000000/templow 10

set room_sensor [ow set /28.86BF80000000]
$room_sensor put temphigh 50

set room_temp [$room_sensor set temperature]
set current_temp [$room_temp get]

owtcl - Man Page

Synopsis

Description

1-Wire

OWFS design

owtcl

Commands

Low-Level Commands

Example

See Also

Programs

Configuration and testing

Language bindings

Clocks

Id

Memory

Switches

Temperature

Humidity

Voltage

Resistance

Multifunction (current, voltage, temperature)

Counter

LCD Screen

Crypto

Pressure

Availability

Author

Referenced By