Casio module 5590

1. In the Timekeeping Mode, hold A until SET stops flashing and the city code appears.
2. Press C to step through the settings: Home City, DST, 12/24-hour format, seconds, hour, minute, year, month, day, then button tone and light duration.
3. On the seconds, press D to reset them to 00.
4. On the hour, minute, year, month or day, press D to go up and B to go down.
5. On the 12/24-hour format, press D or B to switch.
6. Press A to leave the setting mode.

From Casio's guide, page E-21

1. In the Timekeeping Mode, hold A until the city code appears.
2. Press C once to reach the DST setting.
3. Press D or B to switch between ON (summer time) and OFF (standard time).
4. Press A to leave. The DST indicator shows while summer time is on.

From Casio's guide, page E-20

1. In the Timekeeping Mode, hold A until the city code appears.
2. Press D or B to scroll through the city codes.
3. Press A to leave.

From Casio's guide, page E-18

1. Press C four times from the Timekeeping Mode to reach the Alarm Mode.
2. Press D or B to pick the alarm (AL1 to AL5).
3. Hold A until the hour digits flash; the alarm is switched on (ALM shows).
4. Press D or B to set the hour, press C to move to the minutes, then D or B again.
5. Press A to leave the setting mode.

From Casio's guide, page E-36

1. In the Timekeeping Mode, hold A for at least five seconds, until SUB flashes.
2. Press D or B until the mode hand points at the mark at 9 o'clock.
3. Press C: 0:00 flashes.
4. Press D or B until the hour and minute hands are both at 12 o'clock.
5. Press A, then check that the hands match the digital time; repeat if they do not.

From Casio's guide, page E-41

1. Press L in any mode to light the display.
2. To change the duration: in the Timekeeping Mode hold A until the city code appears, then press C ten times.
3. Press D or B to choose 1.5 seconds (1) or 3 seconds (3).
4. Press A to leave.

From Casio's guide, page E-39

1. In the Timekeeping Mode, hold A until the city code appears.
2. Press C nine times: the screen shows KEY♪ or MUTE.
3. Press D or B to switch, then A to leave.

From Casio's guide, page E-44

1. Press C twice from the Timekeeping Mode to reach the Stopwatch Mode.
2. Press D to start, D to stop, and D again to carry on.
3. When it is stopped, press B to reset it.
4. For a split time, press B while it runs (SPLIT flashes); press B again to release it.

From Casio's guide, page E-29

1. Press C three times from the Timekeeping Mode to reach the Countdown Timer Mode.
2. Hold A until the hour digits flash.
3. Press C to move through hours, minutes and seconds, and use D (+) and B (-) to change them.
4. Press A to leave the setting mode.
5. Press D to start and stop the countdown; when it is stopped, press B to reset it.

From Casio's guide, page E-33