US Patent 7142813 Short range wireless device interface with parasitic power supply

A short range wireless protocol is established to/from a processing device, such as a point of sale terminal. Adapters are designed for mating with different ones of commercially available communicating devices (host) using the public switched network. The adapters are arranged to communicate with the host using the host protocol and with the processing device using the established, short range wireless protocol. In one embodiment, power is derived at the adapter using parasitic power from the communication link.