Casio IT-2000W User Manual

Page 33

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33

DOZE/RUN Transit Function

On this terminal the system will reduce the clock speed of the built-in CPU if no activity (access to

the touch panel, keys, COM1, or file) has occurred for a specified period of time (four seconds).

The state in which the CPU clock speed has been reduced is called the "DOZE state" and the state in

which the CPU is operating at full speed is called the "RUN state". If an activity occurs in the

DOZE state, the system returns to the RUN state. The DOZE/RUN transit function automatically

switches between the DOZE and RUN states.

Fig. 2.8

Usually, application programs do not have to anxious about the RUN/DOZE state.

The user may tolerate the operation speed since the system shifts to the RUN state whenever the user

attempts an action.

However, the clock speed is quickly reduced and CPU operation is slow if high-speed processing is

attempted intentionally or if system operation continues without user action (e.g. in a long

calculation). In order to avoid this, disable the power management function by means of the system

library (refer to Chapter 8.6.2 “System Library”.).

Activity causing RUN/DOZE transition:

 Touch panel input
 Key input
 Access to files
 Access to COM1

Note:

If the power management function is disabled by the system library, the Auto Power OFF function

(APO) is also disabled. This is because both the power management function and Auto Power OFF

function use the same activity processing routine.

DOZE

Low speed

Touch panel

Key

COM1

File access

No activity for

a specified period

of time

RUN

Full speed

Touch panel

Key

COM1

File access

Generation of

Activity

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