Atlas Copco PowerMACS 4000, Руководство пользователя

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Peripheral Devices
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An API device can be located on the TCs running a station controller. Each of these TCs may have up to
two API devices making it possible for two clients to access the same cycle data, traces, etc. If more than
one device is configured on a particular TC the value of the parameter
Port No must be used by the client
software to distinguish between them. This is done using the property DeviceInstance of the Api object.
Before being able to access signals in one of the PowerMACS station PLCs via the API you must enable
the input and output areas in the PLC. How this is done is described in the chapter: Access to PLC data.
Note! The PLC input and output data areas are shared with the areas used by the external
communication devices. This means that if an external communication devices is located on TC 1
then the PLC data areas that this device accesses is the same as the area accessed via the API
interface. If you use these simultaneously you must co-ordinate the use of the cells to avoid
unwanted collisions.
If you want to fetch Process data, that is cycle data, events, traces, etc., then you must also add a
Reporter that refers to the API device. Use the Reporter to configure if you want cycle data, events and/or
traces to be accessible from the API. Also, define how cycle data should be formatted, if data is sent in
readable format, i.e. as characters, or in binary format. It is important to understand that it is the
configuration of this reporter that controls the layout and format of the cycle data returned by the API
methods GetCycleData and GetCycleDataBin.
Note! When your client application first instantiate an Api object it can take some time for the
PowerMACS API ActiveX server to start up. If you are experience any problems accessing a
property/method of the newly created Api instance you should make your application wait some
time for the server to be started.