How to set custom altitude value on the Casio SGW 100HD-1AV watch

Other than giving the readings of your current altitude and temperature in the Altimeter mode, you can set your own altitude value. This is a way where you can use it to set it to zero for referencing the height of a climb or as a re-calibration of the altitude reading.

1. Go into the Altimeter mode.
2. Hold the "Adjust" button until the current altitude value start to flash.
3. Use the "Light" (decrease) and "Alti" (increase) buttons to adjust the reference value.
4. Press the "Adjust" button to apply the altitude reference value.

Note: to reset the altitude value to factory value, just simply press both the Light and Alti buttons simultaneously. You will see the off message that indicates the custom value has been reset to factory value.

References or Credits:
http://ftp.casio.co.jp/pub/world_manual/wat/en/qw3202.pdf