Siemens CP 342-5, Руководство пользователя

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Performance data and behavior in operation
5.2 Characteristic data of the DP interface / DP master
CP 342-5 / CP 342-5 FO
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Manual, 10/2011, C79000-G8976-C146-09
Note
Optimum token passing
You can achieve optimum token passing by taking the following measures:
 Assign the lower PROFIBUS addresses to the active nodes.

In the "Highest PROFIBUS address" input box, enter the highest PROFIBUS address of
an active node.
NOTICE
Possible lack of resources with extensive configuration and parameter assignment data
The maximum number of connectable DP slaves as shown in the table can be reduced if
the DP slaves require extensive configuration and parameter assignment data.
In this case, the configuration memory on the CP is not adequate. You will receive a
message in the diagnostics buffer of the CP indicating a lack of resources when you load
the configuration data.
Enhanced DP master functions
As DP master, the CP 342-5/342-5 FO supports the following:
●
SYNC/FREEZE (acyclic)
● Shared input/output (acyclic)
● Enable / disable DP slaves
● Settings that can be changed at run time:
–
own PROFIBUS address
– DP operating mode (no DP, DP master, DP slave active/passive)
● Hardware interrupts / diagnostics interrupts
Hardware and diagnostics interrupts do not need to be evaluated in the user program.
Hardware and diagnostics interrupts are acknowledged automatically by the CP.
You can use single diagnostics to obtain interrupt information.