Technical data

The START /STOP response
The CP is a slave processor system in the S5 rack and must therefore
follow the START/STOP response of the master (here the PLC). After
switching on the power supply, the CP runs through a hardware test
program. Following this, it sets up a management block in the non-backed
up RAM area for every job defined in the module card for internal program
management. It then waits for the start signal from the PLC. In this idle
status, all the programs which process the system tasks or operate the PG
interface are released, however, data exchange with the PLC or with the
bus system is blocked.
The STOP status is defined as follows:
➣
The system programs and the PG interface are enabled.
➣
The virtual links remain established, or continue to be established.
➣
Data transfer on the bus system and interfaces to the PLC are blocked.
The RUN status is defined as follows:
➣
All the programs of the CP and interfaces to the PLC are enabled.
➣
The PG interface is enabled and all ONLINE PG functions can be
performed (exception: changing the database).
➣
Data transfer is enabled and can be monitored with the COM test
functions.
The CP runs through a warm restart whenever the status changes from
STOP to RUN and from RUN to STOP and to RUN again
(resynchronization by repeatedly activating the START/STOP switch on the
PLC). All previously established links are cleared and then re-established.
All buffered data on the CP is lost during this status change
With the COM functions START CP and STOP CP, the PG can also set the
START or STOP request. A STOP status triggered with the START/STOP
switch can only be changed with the START/STOP switch.
B8976060/02 Technical Description and Installation of the CP 5430 TF/CP 5431 FMS
4 - 5 Volume 1