Technical data

Linkage with PLC
112 VIPA GmbH CP486 ⋅ 00/14
Processing a Read Job:
With the handling module FETCH the applications software passes a read job to the CP. This
handling module verifies as well as the handling module SEND the specified parameters, creates a
job unit in bank 0 and sets the status to 'job is running'. By this the CP detects the existence of a new
job and executes this job, as already described under 'Write'. If the CP is able to supply these data, it
stores the data subsequent to the job unit in bank 0 and sets the status to 'finished without error'.
Additionally it sets the identification to 'data for receive available'. With the handling module
CONTROL the applications software allows reading the status instantly. If the data is prepared by
the CP, it can be transmitted to the PC via handling module RECEIVE. If this was successful, the
handling module RECEIVE resets the identification 'data for receive available'. From this time a
new receive job can be entered by the software.
In the case, that the applications software tries to access a new write or read job, while a write or
read job is still running, the applications software receives the identification 'interface busy". This
identifications are placed only by handling modules, they are of no account for the communication
with the CP.
Multiprocessor Operation:
The interface (data structured in banks) is not suitable in the current version for multiprocessor
operation in PC. Only one and the same CPU is allowed to access at any time to a CP implemented
in the PC !!