Casio 5640 Operation Manual page 7

Operation Guide 5640
4. While a setting is flashing, use D (+) and B (–) to change it.
When setting the alarm time using the 12-hour format, take care to set the time
correctly as a.m. (no indicator) or p.m. (P indicator).
5. Press A to exit the setting screen.
To test the alarm
In the Alarm Mode, hold down D to sound the alarm.
E-60
Alarm Countdown
When the current time reaches one hour before an
Alarm countdown
alarm time setting, the alarm on/off indicator will
flash and a countdown of the final 60 minutes will
be displayed while the watch is in the Timekeeping
Mode.
Note
Pressing A while an alarm countdown is in
progress will display the seconds or the day of
Alarm ON/OFF indicator
the week for about two seconds. After that, the
countdown will be displayed again.
When you enter the Timekeeping Mode from another mode while an alarm
countdown is in progress, the seconds or the day of the week will be displayed for
two seconds. After that, the countdown will be displayed.
If an alarm countdown for another alarm starts while a previous alarm countdown is
already in progress, it will be displayed after the ongoing countdown reaches zero
and its alarm sounds.
E-62
The above operation turns on illumination regardless of the current auto light switch
setting.
Illumination is disabled during time calibration signal reception.
Important!
The light source of the analog hand area is an ultraviolet light emitting diode. Do
not look directly at the light source lens.
Do not attempt to remove the light source from this watch to use it for another
purpose.
Do not look directly into the light source located at 6 o'clock.
To change the illumination duration
1. In the Timekeeping Mode, hold down A for at least two seconds until ADJ is
displayed.
When you release A, the city code and city name will scroll from right to left. This
is the setting screen.
The hour and minute hands will automatically move out of the way at this time
(page E-72).
E-64
Warning!
Always make sure you are in a safe place whenever you are looking at the
watch using the auto light switch. Be especially careful when running or
engaged in any other activity that can result in accident or injury. Also take
care that sudden illumination by the auto light switch does not startle or
distract others around you.
When you are wearing the watch, make sure that its auto light switch is
disabled before riding on a bicycle or operating a motorcycle or any other
motor vehicle. Sudden and unintended operation of the auto light switch
can create a distraction, which can result in a traffic accident and serious
personal injury.
Note
This watch features a Full Auto LED, so the auto light switch turns on illumination
only when available light is below a certain level. It does not turn on illumination if
surrounding light is bright.
E-66
Illumination Precautions
Illumination may be hard to see when viewed under direct sunlight.
Illumination turns off automatically whenever an alarm sounds.
Frequent use of illumination runs down the battery.
Auto light switch precautions
Wearing the watch on the inside of your wrist, movement of your arm, or vibration
of your arm can cause frequent activation of the auto light switch and illumination
of the face. To avoid running down the battery, disable the auto light switch
whenever engaging in activities that might cause frequent illumination of the face.
Note that wearing the watch under your sleeve while the auto light switch is
enabled can cause frequent illumination of the face and can run down the battery.
Illumination may not turn on if the face of the watch is more than
15 degrees above or below parallel. Make sure that the back of
your hand is parallel to the ground.
Illumination turns off after the preset illumination duration (page
E-64), even if you keep the watch pointed towards your face.
E-68
To enable or disable an alarm or the Hourly Time Signal
1. In the Alarm Mode, use D to scroll between the
Alarm on indicator
alarms (AL1 to AL5, SIG) until the one you want
is displayed.
2. When the alarm or the Hourly Time Signal you
want is selected, press A to toggle it between
on and off.
The alarm on indicator (when any alarm is on)
and the Hourly Time Signal on indicator (when
the Hourly Time Signal is on) are displayed in
Hourly Time Signal on indicator
all modes.
To stop a sounding alarm
Press any button.
Illumination
Illumination enables easy reading in the dark. The
watch's auto light switch turns on illumination
automatically when you angle the watch towards
your face.
The auto light switch must be enabled (page E-67)
for it to operate.
To turn on illumination manually
Press B in any mode.
You can use the procedure below to select either
1.5 seconds or three seconds as the illumination
duration. When you press B, the face will remain
illuminated for about 1.5 seconds or three seconds,
depending on the current illumination duration
setting.
2. Use C to cycle through the settings until the current illumination duration (LT1 or
LT3) is shown.
See the sequence in step 2 of the procedure under "To change the current time
and date settings manually" (page E-44) for information about how to scroll
between settings.
3. Press D to toggle the illumination duration between three seconds (LT3
displayed) and 1.5 seconds (LT1 displayed).
4. After the setting is the way you want, press A to exit the setting screen.
About the Auto Light Switch
Enabling the auto light switch causes illumination
to turn on whenever you position your wrist as
described below in any mode.
Moving the watch to a position that is parallel to
the ground and then tilting it towards you more
than 40 degrees causes illumination to turn on.
The auto light switch is always disabled, regardless of its enabled/disabled setting,
when any one of the following conditions exists.
While an alarm is sounding
While a receive operation is in progress
To enable or disable the auto light switch
In the Timekeeping Mode, hold down B for at least
three seconds to toggle the auto light switch between
enabled (indicator displayed) and disabled (indicator
not displayed).
The auto light switch indicator appears in all modes
while the auto light switch is enabled.
The auto light switch becomes disabled
automatically whenever battery power drops to
Level 4 (page E-13).
Auto light switch indicator
Static electricity or magnetic force can interfere with proper operation of the auto
light switch. If illumination does not turn on, try moving the watch back to the
starting position (parallel with the ground) and then tilt it back towards your face
again. If this does not work, drop your arm all the way down so it hangs at your
side, and then bring it back up again.
You may notice a very faint clicking sound coming from the watch when it is
shaken back and forth. This sound is caused by mechanical operation of the auto
light switch, and does not indicate a problem with the watch.
E-61
E-63
More than
40°
Wear the watch on the
outside of your wrist
E-65
E-67
E-69