Programming interface
4.2 Error and status messages
SIMATIC 3964R protocol for Windows 9x/XP/7
Installation Manual, 01/2013, J31069-D0131-U001-A2-7218
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4.2
Error and status messages
Messages returned by the functions described in the previous section can be divided into
three classes:
● Positive status messages
● Status error messages
● System error messages
The following error codes are defined in the header file "3964r.h".
Positive status messages
Used by:
•
ComReadState
•
ComWriteState
The status messages are returned when:
● an operation was completed successfully
● an event was not evaluated as an error
Status messages
COM_ST_FREE
Everything OK, no job present
COM_ST_BUSY
A job is currently being processed, no error has occurred up to now.
COM_ST_SUCCESS
The last operation was completed successfully.