Simplified Tango Device Server Model

Intended audience: beginners, developers, administrators, users

This document is directed to beginner developer.

Primary Presentation

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Elements

Block

Description

Device

Abstract concept defined by the TANGO device server object model; it

can be a piece of hardware (an interlock bit) a collection of hardware (a screen attached to a stepper motor)

a logical device (a taper) or a combination of all these (an accelerator).

TANGO Class

From Object Oriented Programming concept, this is the main class that the developer has to implement

DeviceServer

The server (also referred as device server) is a process whose main task is to offer one or more services to one or more clients. To do this, the server has to spend most of its time in a wait loop waiting for clients to connect to it. The devices are hosted in the server process. A server is able to host several classes of devices.

In short, it is a process that export devices available to accept requests). Please refer also to the Glossary, device server instance.

DeviceProperty

Device specific configuration

Attribute

See Glossary, attribute.

Pipe

See Glossary, pipe.

Event

Refer to Events.

Command

See Glossary.

State

The device state is a number which reflects the availability of the device.

Refer to Events

Status

The state of the device as a formatted ascii string

Attributes

Block

Attribute

Description

Device

domain/family/member

To identify the device

Relations

Left Block

Right Block

Multiplicity

Description

Device

TANGO Class

1

Every device belongs to a Tango class

Attribute

Event

0..*

An attribute can have more than one event associated

Device

DeviceProperty

0..*

A device can have more than one Device Property associated

DeviceServer

Device

1..*

Every Device server has many devices inside itself

TANGO Class

Attribute

0..*

A TANGO Class can have more than one Attribute associated

TANGO Class

Command

0..*

A TANGO Class can have more than one Command associated

TANGO Class

Pipe

0..*

A TANGO Class can have more than one Pipe associated