CASIO GC1001-1
Owner's Manual

Module No. 2258
GENERAL GUIDE
� � � � Timekeeping Mode Stopwatch Mode Recall Mode Day Counter Mode Alarm Mode

2258-1

Press C to change from mode to mode. Pressing L in any mode illuminates the display for about 2 seconds. If you do not perform any operation for a few minutes while a setting screen (with flashing digits) is on the display, the watch automatically exits the setting screen. When making settings, note that you can scroll only forward, you cannot scroll back. This means that if you go past the setting you want, you must scroll through all of the available settings again until the one you want reappears.

Press C.

TIMEKEEPING MODE
Hour : Minutes PM indicator Seconds � When the 12-hour format is selected, the indicator P

ABOUT THE BACKLIGHT
� Press L to illuminate the display for about 2 seconds. � The backlight of this watch employs an electro-luminescent (EL) light, which loses its illuminating power after very long term use. � Frequent use of the backlight shortens the battery life. � The watch emits an audible sound whenever the display is illuminated. This does not indicate malfunction of the watch. � The illumination provided by the backlight may be hard to see when viewed under direct sunlight. � The backlight automatically turns off whenever an alarm sounds.

� Press D to toggle between 12-hour and 24-hour timekeeping.

appears on the display for times from noon to 11:59 p.m. to indicate �p.m.� There is no indicator for �a.m.� times. � The indicator P does not appear when you are using 24-hour timekeeping. � The display contents of the watch will not change if you switch between 12-hour and 24-hour timekeeping while the current time is between 1:00 a.m. and 11:59 a.m.

Month - Day Day of week DST on indicator

STOPWATCH MODE
About Lap times and Split times

Setting the Time and Date

There are two different ways to set the time and date. The procedure you should use depends on whether you want to make major changes or minor changes to the current setting. When you want to do this: Make major changes to the time and date setting (before using the watch for the first time, after having the battery replaced, etc.) Make minor adjustments (within about 30 minutes of the current setting) to the time setting Use this procedure:

Lap Times
A lap time is the amount of time it takes for you to get from one point to another during a race. When running on a track, for example, you can time how long it takes you to complete each lap.

Split Times
�To make major time and date settings� A split time is the time from the start of a race until the point that the split is measured. For example, you could measure split times to determine how long it takes for you to get from the starting line to the 5-kilometer mark, the 10-kilometer mark, etc.
Mode indicator

�To zero-reset the minutes and seconds (EASY ADJUST)�

To make major time and date settings
1. While in the Timekeeping Mode, hold down A until the seconds digits flash on the display, indicating the setting screen. 2. Press C to move the flashing in the sequence shown below.
Seconds Day Month DST on/off Year Hour Minutes

The Stopwatch Mode lets you measure elapsed time, lap times, and split times. The range of stopwatch is 23 hours, 59 minutes, 59 seconds. The first hour of a stopwatch operation is measured in units of 1/100 second. After that, elapsed time is measured in units of one second. You can use the EL backlight by pressing L at any time while the stopwatch is operating.

3. While the seconds setting is selected (flashing), press D to reset it to 00. If you press D while the seconds setting is in the range of 30 to 59, the seconds are reset to 00 and 1 is added to the minutes. If the seconds setting is in the range of 00 to 29, the minutes count is unchanged. � While the DST� setting is selected (DST on indicator is flashing), press D to toggle it on (on) and off (OFF). 4. While any other setting is selected (flashing), press D to increase it. Holding down D changes the setting at high speed. 5. After you make the settings you want, press A to exit the setting screen. � The day of the week is automatically set in accordance with the date. � The date can be set within the range of January 1, 2000 to December 31, 2039. � The watch�s built-in full automatic calendar automatically makes allowances for different month lengths and leap years. Once you set the date, there should be no reason to change it except after the replacement of the watch�s battery. �Daylight Saving Time (DST), which is also sometimes called �summer time� advances the time for one hour, as is the custom in some areas during the summer. Remember that not all countries or even local areas use Daylight Saving Time.

Seconds Minutes 1/100 second Lap time

Hours

Minutes Seconds

Lap time

Split time Minutes 1/100 second Seconds

Split time Hours Seconds Minutes

[Up to 1 hour]

[After 1 hour]

To zero-reset the minutes and seconds (EASY ADJUST)
1. A few seconds before the arrival of the time on which you want to zero-reset the minutes and seconds, hold down button B. 2. While still holding down button B, press button D when the time on which you want to zero-reset the minutes and seconds arrives. � The watch beeps to let you know that the minutes and seconds were reset to 00:00. 3. Release buttons B and D. � If you press B and D while the minutes count is in the range of 30 to 59, they are reset to 00 and 1 is added to the hour. If the minutes count is in the range of 00 to 29, the hour count is unchanged. � Though the beep may sound slightly after the point you press both buttons, the zero-reset setting should be correct.

� In the Stopwatch Mode, the upper part of the display shows lap times, while the lower part shows split times. When recalling times in the Recall Mode, you can display either lap times or split times in the upper part of the display. The lower part of the display shows the corresponding lap time or split time number. Note that the lap/split time count value appears on the display in the Recall Mode only. It is not displayed in the Stopwatch Mode.

To measure elapsed time
1. Press D to start the stopwatch. 2. Press D to stop the stopwatch. � You can resume the elapsed time measurement operation by pressing D again. � You can stop the elapsed time measurement operation by pressing D again. 3. While the elapsed time is stopped on the display, press B to clear the stopwatch to all zeros.