APPENDIX C: Acquisition of Suspend/Resume Event and Power Status

Overview

Suspend/Resume event is notified by multiplex interrupt (INT2Fh). If any event such as power

ON/OFF occurs, consequently the interrupt (INT2Fh) will occur. An application can acquire the

event by catching the interrupt. Since the interrupt INT2Fh is multiplex interrupt, application must

reset values in all the registers to the previous values after catching the interrupt and then return the

control to the old-vector.

Broadcast for Power Event

INT2Fh

Input:

AH = 53h

AL = 0Bh

BH = (Reserved)

BL = 1 System wait request

=2 System abortion request

=3 Normal resume notification (if the method of the previous OFF is by normal suspend.)

=4 Critical resume notification (if the method of the previous OFF is by critical suspend.)

=5 Battery state notification

Output:

BH = 80h Application refuses request.

= 00h Others

The power event is notified by POWER.EXE. In order to use the notification function, POWER.EXE must be pre-installed. An application must check first if the POWER.EXE has been installed or not by using the functions detailed below.

Function to Check POWER.EXE

INT2Fh

Input:

AH = 54h

AL = 00h

Output:

 

AX = 5400h

Not installed.

= others

Version numbers

BH = 50h

“P”

BL = 4Dh

“M”

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Casio IT-2000W manual Broadcast for Power Event, Function to Check POWER.EXE, INT2Fh