A. Except in a period of emergency determined by an officer of the fire or police department, or in compliance with the directions of a police officer or traffic-control sign or signal, when any vehicle is parked in any parking space alongside or next to which a parking meter is located, the operator of such vehicle shall, upon entering the said parking meter space, immediately deposit or cause to be deposited in said meter such proper coin or coins of the United States as are required for such parking meter and as are designated by proper directions on the meter, and when required by the direction on the meter, the operator of such vehicle, after the deposit of the proper coin or coins, shall also set in operation the timing mechanism on such meter in accordance with directions properly appearing thereon, and failure to deposit such proper coin or coins, and to set the timing mechanism in operation when so required, shall constitute a violation of this chapter.
B. Upon the deposit of such coin or coins and the setting of the timing mechanism in operation when so required, the parking space may be lawfully occupied by such vehicle during the period that such meter indicates legal parking, not exceeding the period of time which has been prescribed as the legal parking time limit for the part of the street in which said parking space is located; provided, that any person placing a vehicle in a parking meter space adjacent to a meter which indicates that unused time has been left in the meter by a previous occupant shall not be required to deposit a coin so long as his occupancy of said space does not exceed the indicated unused parking time.
C. If said vehicle remains parked in any such parking space beyond the parking time limit set for such parking space, or if the meter indicates illegal parking, then, and in that event, such vehicle shall be considered as parking overtime and beyond the period of legal parking time, and such parking shall be deemed a violation of this chapter.
D. Each period of time equivalent to the legal parking time limit set for any parking space, or fraction of such period, during which a vehicle remains parked in such parking space while the parking meter is showing a signal indicating that such space is illegally in use, shall constitute a separate offense under this chapter.