Patent ID: 7508687

Claim:
A method comprising: (a) receiving an AC signal onto a DC power supply connector of an electrical device, wherein the DC power supply connector has only two contacts, one of the contacts being a ground contact, the other of the contacts being a DC supply voltage contact, and wherein there is substantially no DC voltage between the two contacts during said receiving; (b) using the AC signal to generate a local DC supply voltage on the electrical device; (c) using the local DC supply voltage to power a reading of a memory in the electrical device such that information is output from the memory; (d) using the local DC supply voltage to power an outputting of the information onto the DC power supply connector, wherein during the outputting there is substantially no DC voltage between the two contacts of the DC power supply connector; and (e) powering the electrical device from a DC voltage received after (d) onto the DC power supply connector of the electrical device.