Name: Casio G-shock GA-2100-4AER
Brand: Casio
SKU: 1134666
Rating: 84 (2 reviews)

Operation Guide 5611
E-9
To do this: Enter this mode: See:
Use the stopwatch to measure elapsed time Stopwatch Mode E-26
Use the countdown timer Countdown Timer Mode E-30
Set an alarm time Alarm Mode E-33
E-8
Mode Reference Guide
The mode you should select depends on what you want to do.
To do this: Enter this mode: See:
x View the current date in the Home City
x Configure Home City and daylight saving time (DST)
settings
x Configure time and date settings
x View the World Time city and time
x Change the display illumination duration setting
x Enable/disable the button operation tone
Timekeeping Mode E-15
View the current time in one of 48 cities (31 time
zones) around the globe
World Time Mode E-23
E-7E-6
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-43
Main Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-45
Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-46
Operating Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-49
User Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-60
E-5
Using the Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-33
To enter the Alarm Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-33
To set an alarm time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-34
To test the alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-35
To turn an alarm and the Hourly Time Signal on and off . . . . . . . . . . . . . . . . . E-36
To stop the alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-36
Illumination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-37
To turn on illumination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-37
To change the illumination duration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-38
Adjusting Hand Positions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-39
Button Operation Tone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-41
To turn the button operation tone on and off . . . . . . . . . . . . . . . . . . . . . . . . . E-42
E-4
Checking the Current Time in a Different Time Zone . . . . . . . . . . . . . . . . . . . E-23
To enter the World Time Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-24
To view the time in another time zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-24
To specify standard time or daylight saving time (DST) for a city . . . . . . . . . . . E-25
Using the Stopwatch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-26
To enter the Stopwatch Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-26
To perform an elapsed time operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-27
To pause at a split time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-27
To measure two finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-27
Countdown Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-30
To enter the Countdown Timer Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-30
To configure the countdown timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-31
To perform a countdown timer operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-32
To stop the alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-32
E-3
Contents
About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-1
Things to check before using the watch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-2
Mode Reference Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-8
Timekeeping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-15
Configuring Home City Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-16
To configure Home City settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-16
To change the Daylight Saving Time (summer time) setting . . . . . . . . . . . . . . E-18
Adjusting the Digital Time and Date Settings . . . . . . . . . . . . . . . . . . . . . . . . . E-19
To configure the digital time and date settings . . . . . . . . . . . . . . . . . . . . . . . . E-19
E-2
Things to check before using the watch
1. Check the Home City and the daylight saving time (DST) setting.
Use the procedure under “To configure Home City settings” (page E-16) to configure
your Home City and daylight saving time settings.
Important!
x Proper World Time Mode data depends on correct Home City, time, and date
settings in the Timekeeping Mode. Make sure you configure these settings
correctly.
2. Set the current time.
x See “Adjusting the Digital Time and Date Settings” (page E-19).
The watch is now ready for use.
E-1
About This Manual
x Depending on the model of your watch, display text
appears either as dark figures on a light background, or
light figures on a dark background. All sample displays
in this manual are shown using dark figures on a light
background.
x Button operations are indicated using the letters shown
in the illustration.
x Note that the product illustrations in this manual are
intended for reference only, and so the actual product
may appear somewhat different than depicted by an
illustration.
E
ENGLISH
Congratulations upon your selection of this CASIO watch.
To ensure that this watch provides you with the years of service for which it is
designed, carefully read and follow the instructions in this manual, especially the
information under “Operating Precautions” and “User Maintenance”.
MA1906-EB
©
2019 CASIO COMPUTER CO., LTD.

Need help?

Number of questions: 4

Do you have a question about the Casio G-shock GA-2100-4AER or do you need help? Ask your question here. Provide a clear and comprehensive description of the issue and your question. The more detail you provide for your issue and question, the easier it will be for other Casio G-shock GA-2100-4AER owners to properly answer your question.

Perry Atristain, 8-8-2020 05:25:26 1 comment

what does HND on the digital display stand for?

John, 28-3-2021 20:36:02

It is to let you know that the hands have been moved away from the digital display and are not currently showing the time

Answer this question

Syed Razaleigh, 8-12-2020 05:53:11 1 comment

Do the hands of GA2100 glow in the dark?

Sok Nisong , 11-1-2021 14:19:21

How to set a date

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Pete, 15-11-2020 15:29:55 No comments

I just got mine and the alarm, hourly beep, etc. does not sound. What do I do, or is it defective?

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Steve , 5-5-2020 20:53:51 1 comment

I have set the watch to London time and set the date month and year correctly. However the day sun dial does not record the correct day of the week. Hiw can I resolve this issue

Luis, 23-9-2020 00:53:24

You might have to adjust the hand zero position of your subdial. Press the a button for about 6 seconds (two beeps) and the screen should read "SUB". Adjust the position of the day hand using the B and D buttons and finish the process pressing the A btn.

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About the Casio G-shock GA-2100-4AER

View the manual for the Casio G-shock GA-2100-4AER here, for free. This manual comes under the category Watches and has been rated by 2 people with an average of a 8.4. This manual is available in the following languages: English. Do you have a question about the Casio G-shock GA-2100-4AER or do you need help? Ask your question here

Casio G-shock GA-2100-4AER specifications

General

Brand	Casio
Model	G-shock GA-2100-4AER
Product	Watch
EAN	4549526241758
Language	English
Filetype	PDF

Technical details

Watch type	Wrist watch
Waterproof	✓
Watch dial type	Analog & LCD dial
Chronometer	✓
Chronograph	-
Mechanism type	-
Clock mode	12h/24h
Calendar	✓
Timer	1/1 s - 24 h
Stopwatch	✓
Countdown timer	✓
Shockproof	✓
Backlight type	EL
Accuracy	-15 - 15 sec/month
Alarm function	✓
Stopwatch accuracy	0.01 s
Stopwatch measuring capacity	1/100 s - 24 h
Calendar type	Day

Weight & dimensions

Weight	51 g
Width	45.4 mm
Depth	11.8 mm
Height	48.5 mm

Design

Band main colour	Red
Housing colour	Red
Watch case material	Carbon,Resin
Band material	Resin
Case shape	Round
Watch dial main colour	Red
Product design	Sport
Watch marker colour	Red
Watch marker style	No markers
Watch glass type	Mineral