Casio PA-2400W 5. I/O Bootup Library 5.1 Overview, 5.2 Function

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5. I/O Bootup Library
5.1 Overview
The I/O bootup library monitors the connection status of dedicated I/O Box and notifies user of the status.
5.2 Function
This library supports only one function, iobox_chk(). The iobox_chk() function monitors and detects, for a
specified period, whether PA-2400W is mounted on I/O Box, and returns the result (mounting detected,
timeout error, or error). Each time this function is used, it is necessary to also execute "Permit interrupt, Wait
for interrupt and time-out, and Prohibit interrupt". The following diagram shows the range covered by this
library.
Fig. 5.1
Because the interrupt signals are detected by their signal levels, they can be detected even if the order of (1 )
and (2) is changed. (The connection status can be detected whether this function is called before or after the
PA-2400W is mounted on I/O Box is mounted, unless a timeout occurs.)
(3) I/O Box ON Signal
PA-2400W
(2) Mounting
I/O PORT: 0
IOBOX1.DLL
User Application
(1) iobox_chk ( TIME_OUT_SEC ) ;
(4) Timeout
(5) Return Detection, Timeout
Error
I/O Box
Karnel
(4) Interrupt Signal