Renu Electronics GWY-500, Руководство пользователя

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Getting Started
17
Doc No: UMAN\GWY-500-B\0106
REVISION 4
At the slave 1. Protection mechanisms at the slave.
The slave uses the watchdog control to detect failures of the master or the transmission
line. If no data communication with the master occurs within the watchdog control
interval, the slave automatically switches its outputs to the fail-safe status. This
mechanism can be enabled or disabled for each individual slave.
Also, access protection is available for the inputs and outputs of the DP slaves operat
ing in multi-master systems. This ensures that direct access can only be performed by
the authorised master. For other masters, the slaves offer an image of their inputs and
outputs, which can be read by any master, even without access rights.
3.1.3.5 Network States
PROFIBUS-DP distinguishes four different network states.
Off-line 1. Off-line
Communication between all DP participants is stopped.
Stop 2. Stop
Communication between DPM1 and DP slaves is stopped. Only communication
between DPM1 and DPM2 is possible.
Clear 3. Clear
DPM1 master attempts to set parameters, check the configuration, and subsequently
perform data exchange with its associated DP-slaves. The data exchange comprises
reading the inputs of the DP-slaves and writing zero’s to the outputs of the DP-slaves.
Operate 4. Operate
DPM1 master exchanges data with its assigned slaves, inputs are read and outputs are
written. Beside this, the DPM1 cyclically sends its local status to all assigned DP
slaves (with a multicast message) at a configurable time interval.
Auto_Clear When an error occurs during the data transfer phase of the DPM1, the ‘Auto_Clear’
configuration setting determines the subsequent actions. If this parameter is set to
false, the DPM1 remains in the ‘Operate’ state. If set to true, the DPM1 switches the
outputs of all assigned DP slaves to the fail-safe state and the network state changes to
the ‘Clear’ state.
3.1.4 Device Data Base Files
GSD-file To achieve straightforward configuration of a PROFIBUS-DP network, the characteristic
features of a device are specified in a file. This file is called a GSD-file
(Gerätestammdaten file). The language of the GSD file is expressed with the last letter
from the extension, *.GS?:
Default : = GSD
English : = GSE
Deutsch : = GSG
Italian : = GSI
Portugees : = GSP
Spanish : = GSS
The GSD files are prepared individually by the vendor for each type of device, according
to a fixed format. Some parameters are mandatory, some have a default value and some
are optional. The device data base file is divided into three parts: