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Generic Slave Device DTM
Section 2-5
Fail-Safe Behaviour
The Fail-Safe Behaviour box defines whether or not the PROFIBUS Master
Unit will in CLEAR mode send an empty output data message to the slave
device or a data message containing zeros. Depending on the PROFIBUS DP
slave device, an empty data message, may be required, if the slave device
performs user specific functions in CLEAR mode, and during which the out-
puts can not be set to zero.
Error on Cyclic Data
Exchange
The Error on Cyclic Data Exchange settings box, defines the behaviour of the
PROFIBUS Master Units on the PROFIBUS network with respect to this par-
ticular slave device, in case it fails to respond during I/O data exchange.
Depending on the setting, the Master Unit will either continue sending I/O
data exchange messages to the slave device, or abort I/O data exchange,
and continue with requesting the slave diagnostics data. When continuing
sending I/O data exchange data, the slave’s diagnostics data will not be
updated.
Note
A slave’s failure to respond during I/O data exchange will always be reported
to the PLC CPU, by resetting the corresponding Slave Data_Exchange Active
flags in the CIO Words
(
refer to the CS1/CJ1W-PRM21 Operation Manual,
W409-E2-
@
). If Auto-CLEAR has been enabled, the failure to respond will
result in the PROFIBUS Master Unit switching to CLEAR mode, based on this
CIO flag.
Diagnostics Update Delay
The Diagnostics Update Delay defines the number of PROFIBUS DP cycles
during which the PROFIBUS Master Unit will ignore diagnostics message
returned from the slave containing the Prm_Req flag. This flag indicates that
the Master Unit should re-parameterize the slave, but in the case of reduced
performance slave devices, the returned flag also indicates that the slave
Control
Description
DPV1 Compliant
The Check I/O configuration message will contain PROFI-
BUS DP-V1 Data type definitions in the special identifier
format data parts and the slave device will perform the
check on this assumption.
EN50170 Compliant
The Check I/O configuration message will contain stan-
dard PROFIBUS DP Data type definitions as well as ven-
dor specific data types and the slave device will perform
the check on this assumption.
Control
Description
Send zeros in Clear
mode
When in CLEAR mode, the PROFIBUS Master Unit will
send a full output data message to the slave device, but
the message will contain all zeros.
Send no data in Clear
mode
When in CLEAR mode, the PROFIBUS Master Unit will
send an empty output data message (i.e. no data bytes,
only the message header) to the slave device.
Control
Description
Continue if slave not
responding
The PROFIBUS Master Unit will continue to send I/O data
exchange messages, when the slave device fails to
respond. The diagnostics data of the slave will not be
updated.
Abort if slave not
responding
The PROFIBUS Master Unit will abort the data exchange
with the slave device, and continue to send diagnostics
request message to the slave, until it responds. The diag-
nostics data of the slave will be updated accordingly.