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5.4 Use of iobox_chk
Internally, this function creates an event object of I/O Box and waits for the object for a specified time.
During the wait time, it is possible to dispatch another task. Therefore, there are two ways of usage as stated
below.

Sequential Mode

This mode is to call the function and check if the PA-2400W is connected to I/O Box. After a confirmation
on the session establishment, the process continue to a next job.
Fig. 5.2

Multiple-Thread Mode

Main program creates a thread (CreateThread( ) ) for session with I/O Box and calls the function within
this thread to wait for the establishment of session with the I/O Box. While the main program waits in the
loop, it makes necessary processes of each message.
After the created thread confirms the session, the sub-thread throws a message to the main program which
makes the main program confirms the session. Refer to Chapter 5.5 “Sample Program” on page 38 for a
sample program to use the function in “Multiple-Thread Mode”.
Next Job
Place PA-2400W on I/O Box.
iobox_chk (30)
Connected ?
Error Process
No
Yes