PC Control / Profi Control 645-12M Instruction Manual pdf - Kuhnke

4.9.2.6. Service 6: synchronise DP slave outputs
PC Control 645-12M on PROFIBUS
This service allows you to synchronise the output values,
as transferred by cyclic data frames, of specific DP slaves,
entire groups (multicast) or all DP slaves in the network
(broadcast).
A Sync command puts the DP slave into Sync mode. The
output data sent by the DP master are buffered in the DP
slave and not forwarded to the outputs.
With the next Sync command, the buffered values are forwarded
to the outputs.
The Unsync service cancels the Sync mode and causes the
output states to be updated cyclically as usual.
Parameter field
Byte
Parameter
0
B yte 1 Error#
Input
Descriptio n
Dienst
6 Specifies the service
0 No error
1 Parameter error
2 Service not possible
7 Internal error
0...99
Number of DP slave
B yte 2 Station#
127
Global address, broadcas t
B yte 3 Group#
( 0)1... 8 Group-Ident (0 = none)
Byte
4
Action
0...127
Unsync; bit 7 = 0
128...255
Sync; bit 7 = 1
Station
Specify the station and group numbers of the DP slave(s)
that the service is to apply to.
For further details please refer to chapter "4.9.2.3.1.
Choosing a station and group".
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