User Documentation

Program development
System manual
2696790000/02/04.2020
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7.3 Device Service
The DeviceService is a software service t manages, controls and monitors
individual programs on the control. The DeviceService can collect and for-
ward information (e.g. error messages) of the programs.
The DeviceService runs as an independent process and starts automatically
once the operating system has been fully loaded.
Each program to be managed by the DeviceService must be defined on the
control as DeviceServiceItem.
7.3.1 Defined state model
The DeviceService is responsible for software state transitions that do affect
multiple software subsystems running on the same device.
Fig.7-5: DeviceService state model
States
State Description
OsReady
The operating system is ready and the De-
vice Service is available. Programs not initial-
ized.
Stop
The programs are running, Applications not
running
Run Programs and applications are running
State transitions may be triggered explicitly by software components running
on the local device, the operating elements on the device, or by remote
clients (e.g. programming tools).
The following commands can be performed by the DeviceService for the
state transition of multiple programs on the current device:
Command
Command
type
Description
Start Controller State transition
This status transition is run automatically once the de-
vice is started. The status changes from "OsReady" to
"Run".