Network States - Omron C200HW-PRM21 Operation Manuals

PROFIBUS-DP characteristics

1-4-5 Network states

Offline
Stop
Clear
Operate
Auto_clear
Fail-safe state
can only be performed by the authorised master. For all other masters, the
slaves offer an image of their inputs and outputs which can be read from
any master, even without access rights.
PROFIBUS-DP distinguishes four different states.
• Offline
Communication with all DP participants is stopped.
• Stop
Communication between DPM1 and DP slaves is stopped. Only communi-
cation between DPM1 and DPM2 is possible.
• Clear
DPM1 master tries to set parameters, check the configuration, and
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
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) at a configurable time
interval.
When an error occurs during the data transfer phase of the DPM1, the
'Auto_clear' configuration parameter 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.
Section 1-4
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