erni , what do you mean by arming sequence?
When you connect the battery to the ESC (and motor), the controller in the ESC goes through a process where among othher things it determins if it is safe to start the motor. While doing this it produces some tones using the motorwindings as a speaker. It ususally takes 1-2 secs. Some ESC's need full throttle during this sequence others no throttle and others combinations, that why it is the hard part.
In the old days (until last year I think) the Turnigy Plush ESC's used am Atmega8, processor but for somme reason they have changed that.