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2.3.8 Buzzer
This terminal is provided with a buzzer function that is compatible, via an appropriate interface, with
the IBM PC. The application side can sound this buzzer by controlling the I/O port assigned to 61h.
It is also possible to modify the sound frequency by controlling channel 2 of the timer.
For information about the method used to modify the frequency refer to the hardware manual of the
PC/AT compatible machine.
Use of Buzzer From the System
The IT-2000 system uses the buzzer in the following cases:
At power on (boot)
If the power is turned off by the Power switch.
If the PC card is inserted/removed
If a key input is accepted (for matrix key and keypad). Enable/disable can be set with the system
library. (refer to Chapter 7.6.2 “System Library”)
If the key buffer is full
At a low battery voltage (LB1)
If an alarm interrupt (INT4Ah) occurs
If the battery cover is opened while the power is on.
At a hardware anomaly
For calibration and System Menu operation
Setting Volume of Buzzer
The buzzer volume can be set with System Menu or from the system library.
The volume can be set to one of the four levels: OFF/Small/Medium/Large.
For more information about System Menu and the system library refer to Chapter 3 “System Menu"
and Chapter 7.6.2 “System Library” respectively.