Casio 2556 User Manual

USER’S GUIDE 2556

About This Manual

• Button operations are indicated using the letters shown
in the illustration.

• Each section of this manual provides you with the
information you need to perform operations in each
mode. Further details and technical information can be
found in the “Reference” section.

General Guide

• Press C to change from mode to mode.

• In any mode, press B to illuminate the display.

World Time Mode

Timekeeping Mode

Press C.

▲

▲

Timekeeping

Use the Timekeeping Mode to set and view the current time and date.

• Pressing D displays the Last Signal screen (date and time the time calibration

signal was last received) in the Timekeeping Mode.

Month – Day Hour : Minutes Seconds

Press D.

▲

▲

PM
indicator

Day of week

Current Time Setting

This watch automatically adjusts its time setting in accordance with a time calibration
signal. You can also perform a manual procedure to set the time and date, when
necessary.

• Before using the watch in the Continental United States, first use the procedure
under “Setting Up the Watch for Use in the Continental United States” to set the time
in accordance with a time calibration signal.

• Note that after you set your Home City (the city where you normally use the watch)
code, you must also turn on the watch’s time calibration signal receiver if you want to
enable auto time calibration. See “About Auto Receive” for more information.

• See “Setting the Time and Date Manually” for information about manual settings.

Setting Up the Watch for Use in the Continental United States

You need to make the following three settings before using this watch in the
Continental United States. The following provides a general overview of the setting
procedure. For full details, see “Setting the Time and Date Manually” and “Time
Calibration Signal Reception”.

• Specify the city code for your Home City (the city where you will normally use the
watch).

• Select the auto summer time (DST) setting.

• Perform the manual time calibration signal receive operation to set the current time.

To set up the watch for use in the Continental United States

Receive indicator

1. In the Timekeeping Mode, hold down A until the

current auto receive on/off setting to flash, which
indicates the setting screen.

2. Press C twice to move the flashing to the city code

setting.

3. Use D(+) and B(–) to select the city code you want to

use as your Home City.

City code

• The following are the city codes for major cities in the
Continental United States time zones.

LAX: Los Angeles, San Francisco, Las Vegas, Seattle
DEN: Denver, El Paso
CHI: Chicago, Houston, Dallas/Fort Worth, New Orleans
NYC: New York, Detroit, Miami, Boston

4. Press C to display the summer time (DST) setting

screen.

5. Use D to select A (auto DST).

• Auto DST specifies auto switching between Daylight
Saving Time and Standard Time.

6. Press A to exit the setting screen.

7. Hold down D for about two seconds until the watch

beeps.

• Release D and the message RC! appears to indicate

that signal reception has started.

• Time calibration signal reception takes from two to six
minutes. Take care that you do not move the watch
during this time.

Receive date

Last Signal Screen

Alternate at the
1 second interval

▲

▲

Receive time

Alarm Mode

▲

Stopwatch Mode

▲

• If the watch is indoors, we recommend that you place the watch near a window to
allow better signal reception.

• After signal reception is complete, the display of the watch changes to the Last
Signal screen.

Time Calibration Signal Reception

This watch is designed to pick up a time calibration signal and update its time setting
in accordance with the signal. There are two different methods you can use to receive
the signal: Auto Receive and Manual Receive. With Auto Receive, the watch
automatically receives the calibration signal three times each day and makes
appropriate adjustments. With Manual Receive, you perform a specific button
operation to receive the calibration signal.
Before performing a signal receive operation, remove the watch from your wrist and
position it as shown in the illustrations below.

• If your watch has a resin band, pass the end of the band through the band loop and
place the watch on a stable surface.

Note

• If you are using the time calibration signal to set the time for this watch, be sure to
correctly set your Home City. Otherwise, there is the chance that the watch will not
set the correct time. See “Setting the Time and Date Manually” for details.

• Note that signal reception is possible only when the watch is within range of a time
calibration signal transmitter, and a city code that supports signal reception is
selected as the Home City code.

• The current time setting in accordance with the time calibration signal takes priority
over any time settings you make.

• Auto receive is turned on when the watch is shipped from the factory.

• See the information under “Time Calibration Signal Reception” if you experience

problems with time calibration signal reception.

To perform manual time calibration signal reception

1. Place the watch on a stable surface so its top (12 o'clock side) is facing in the

general direction of the signal transmitter.

• Note that signal reception is poor if the watch is on its back or side.

Receive indicator

Note

• To interrupt a receive operation and return to the Timekeeping Mode, press D.

• If the receive operation is unsuccessful, the message ERR appears on the display

for about one or two minutes. After that, the watch returns to the Timekeeping Mode.

• You can also change from the Last Signal or ERR screen to the normal timekeeping
screen by pressing D.

Resin band Metal band

Pass through band loop.

2. In the Timekeeping Mode, hold down D for about two

seconds until the watch beeps.

• Release D and the message RC! appears to indicate

that signal reception has started.

• Time calibration signal reception takes from two to six
minutes. Take care that you do not move the watch
during this time.

• After signal reception is complete, the display of the
watch changes to the Last Signal screen.

• The receive indicator indicates that the time calibration
reception attempt was successful.

Date Alert Mode

▲

Time Recorder Mode

▲

1

USER’S GUIDE 2556

About the Receive Indicator

The receive indicator shows the strength of the calibration signal being received. For best
reception, be sure to keep the watch in a location where signal strength is strongest.

) appears.

DST

Hour

Strong

ONON

ON) and off (

ONON

12/24-Hour
Forma t

Seconds

OFOF

OF).

OFOF

Weak

• Even in an area where signal strength is strong, it takes about 10 seconds for signal
reception to stabilize enough for the receive indicator to indicate signal strength.

• Use the receive indicator as a guide for checking signal strength and for finding the
best location for the watch during signal receive operations.

• The receive indicator remains on the display in all modes following reception of the
time calibration signal and calibration of the watch’s time setting. The receive
indicator does not appear if signal reception was unsuccessful or after manual
adjustment of the current time setting.

About Auto Receive

When auto receive is turned on, the watch automatically starts to receive the time
calibration signal when the time in the Timekeeping Mode reaches 2:00 AM, 4:00 AM
and 6:00 AM each day (calibration times).

Note

• The auto receive operation is performed only if the watch is in the Timekeeping or
World Time Mode when one of the calibration times is reached.
It is not performed if a calibration time is reached while you are making settings
(while settings are flashing on the display), while an alarm is sounding.

• Auto receipt of the calibration signal is designed to be performed early in the
morning, while you sleep (provided that the Timekeeping Mode time is set correctly).
Before going to bed for the night, remove the watch from your wrist, and put it in a
location where it can easily receive the signal.

• The receive indicator indicates that either the 2:00 AM, 4:00 AM, or 6:00 AM
calibration signal reception was successful. Note, however, that the receive indicator
is cleared from the display at 3:00 AM each day.

• If you do not see the receive indicator except for the above reason, it means there
was some problem with the calibration reception operation. Either perform reception
manually, or make sure the watch is set up properly to receive the time calibration
signal for the next automatic reception time.

• Though this watch is designed to receive both time data (hour, minutes, seconds)
and date data (year, month, day), certain signal conditions can limit reception to time
data only.

• The receive indicator (
receive both time and date data. It does not appear when only time data is received.
When time and date data is received: Receive indicator (
When time data only is received: Receive indicator (

• Normally, the signal reception date shown by the Last Signal screen is the date data
included in the received time calibration signal. When only time data is received,
however, the Last Signal screen shows date as kept in the Timekeeping Mode at the
time of signal reception.

• When auto receive is turned on, the watch receives the calibration signal for two to
six minutes each day when the Timekeeping Mode time reaches 2:00 AM, 4:00 AM
and 6:00 AM. Do not operate any of the watch’s buttons within six minutes prior to or
following the calibration times. Doing so can interfere with correct calibration.

• Remember that reception of the calibration signal depends on the time kept in the
Timekeeping Mode. The receive operation will be performed whenever the display
shows 2:00 AM, 4:00 AM and 6:00 AM, regardless of whether or not the
Timekeeping Mode time is actually the correct time.

• When two or three receptions are successful, the watch uses the data of the last
reception for calibration. When only one reception is successful, the watch uses the
data of the successful reception.

To turn auto receive on and off

Setting the Time and Date Manually

Make sure you select your Home City code (the city code whose time and date you
are setting) before change the current time and date settings. World Time Mode times
are all displayed in accordance with the Timekeeping Mode settings. Because of this,
World Time Mode times will not be correct if you do not select the proper Home City
code before setting the time and date in the Timekeeping Mode.

To set the current time and date manually

Auto

Receive

Day

3. When the setting you want to change is flashing, use B and/or D to change it as

described below.

Auto Receive

Frequency

City code

) appears only when the watch is able to successfully

) does not appear.

1. In the Timekeeping Mode, hold down A until the

current auto receive on/off setting to flash, which
indicates the setting screen.

2. Press D to toggle auto receive on (

3. Press A to exit the setting screen.

1. In the Timekeeping Mode, hold down A until the

current auto receive on/off setting to flash, which
indicates the setting screen.

2. Press C to move the flashing in the sequence shown

below to select other settings.

Year Minutes

ScreenSetting

City Code

Button Operations

Press D to toggle auto receive on and off.

When NYC, CHI, DEN, LAX, ANC, or HNL
is selected as Home City Code, USA
flashes. When one of the other city codes is
selected as Home City Code, --- flashes.

Use D (+) and B (–) to change the
setting.

Frequency

Month

DST

12/24-Hour format

Hour, Minutes

Seconds

Year

Month, Day

4. Press A to exit the setting screen.

• The auto receive setting is used for time calibration signal reception only. See “About
Auto Receive” for details.

• See “City Code Table” for a complete list of available city codes.

• Resetting the seconds to 00 while the current count is in the range of 30 to 59

causes the minutes to be increased by 1. In the range of 00 to 29, the seconds are
reset to 00 without changing the minutes.

ScreenSetting

Press D to toggle between 12-hour (12H)

Button Operations

Press D to toggle between Daylight Saving

ONON

Time (

ON) and standard time (

ONON

• Pressing D performs a different operation

when NYC, CHI, DEN, LAX, ANC or HNL
is selected as Home City Code. See “Auto
Summer Time (DST) Switching”.

and 24-hour (24H) timekeeping.
Use D (+) and B (–) to change the

setting.
Press D to reset the seconds to 00.
Use D (+) and B (–) to change the

setting.

OFOF

OF).

OFOF

World Time

The World Time shows the current time in 30 cities (29

Home city time

To view the time in another city code

In the World Time Mode, press D to scroll city codes (time zones) to the east or A to
scroll to the west.

• For full information on city codes, see the “City Code Table”.

Alarms

Home city time

Alarm time (Hour : Minutes)
Countdown

(Hours : Minutes Seconds)

DST indicator

City code

Current time in the
selected city code
(Hour : Minutes Seconds)

Alarm number

Target alarm screen

To set an alarm time

time zones) around the world.

• If the current time shown for a city is wrong, check your
Timekeeping Mode time and Home City settings and
make the necessary changes.

• You can change the DST (Daylight Saving Time)/
Standard Time settings for each city code in the
Timekeeping Mode.

• The watch will perform a signal receive operation even if
it is in the World Time Mode when a calibration time is
reached. If this happens, the World Time Mode time
settings will be adjusted in accordance with the
Timekeeping Mode’s Home City time.

• All of the operations in this section are performed in the
World Time Mode, which you enter by pressing C.

The Alarm Mode gives you a choice of four one-time
alarms and one snooze alarm. One of the one-time
alarms functions as a “target alarm,” which counts the
time remaining from the current Timekeeping Mode time
to the target alarm time.
Also use the Alarm Mode to turn the Hourly Time Signal
(SIG) on and off.

• There are five alarms numbered AL1 through AL3,
TAL,and SNZ. You can configure SNZ as a

snooze alarm only. Alarms AL1 through TAL
(target alarm) can be used as one-time alarms only.

• Alarm settings (and Hourly Time Signal settings) are
available in the Alarm Mode, which you enter by
pressing C.

1. In the Alarm Mode, use D to scroll through the alarm

screens until the one whose time you want to set is
displayed.

AL1 AL2 AL3

SIG SNZ TAL

2. After you select an alarm, hold down A until the hour

setting of the alarm time starts to flash, which indicates
the setting screen.

• This operation automatically turns on the alarm.

3. Use C to move the flashing in the sequence shown

below to select other settings.

MinutesHour

4. While a setting is flashing, use D and B to change it.

• While the hour or minute setting is flashing, use D
(+) and B (–) to change it.

• While a one-time alarm or the snooze on/off setting is
flashing, use D to toggle it on (ON) and off (OF).

5. Press A to exit the setting screen.

• 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).

On/off status

2