On my cistern it has half moon button and round button, the half moon half encircling the round one. The round button is the short flush when pressed goes down on its own.
Pressing the half moon shaped button presses down both for full flush. Some people get mixed up thinking half moon button is short flush.
NOTE: I haven't mentioned the manufactures name of my cistern like you so you have to guess like I have if your one is the same as mine. Get it!.
Bob, May 2012
