Patent ID: 7872201

Claim:
A system, comprising: a weighing scale having weighing functionality controlled by an operating parameter and having stored thereon a plurality of differing values of the operating parameter, said weighing scale having a controller operatively configured to enter a programming mode so as to allow a programmer to set a value of the operating parameter by electronically selecting from among the plurality of differing values stored on said weighing scale; wherein: said weighing scale further includes a power port for receiving external electrical power for powering said weighing scale during use of the weighing functionality and said controller is responsive to a key signal so as to cause said weighing scale to enter the programming mode, said weighing scale further including a signal receiver in electrical communication with said power port so as to receive the key signal; and the key signal is an AC signal having a frequency and said power port is a DC power port, said signal receiver configured to identify the frequency as corresponding to the key signal.