Canon D20 - Manual (Page 201)

On-Screen Information
201
* : Regular orientation, : Held vertically
The camera detects the shooting orientation and adjusts settings for optimal shots.
Orientation is also detected during playback, and in either orientation, the camera
automatically rotates images as needed.
However, the orientation may not be detected correctly when the camera is pointed
straight up or down.
An on-screen icon or message indicates the battery charge level.
Battery Level
Display Details
Sufficient charge
Slightly depleted, but sufficient
(Blinking red) Nearly depleted – charge the battery soon
[Change the battery pack.] Depleted – charge the battery immediately