Programmable multiple-standard digital communications system

A circuit for communicating digital data over a wire, said circuit comprising:

• a data processor programmed for use with digital data in at least two different communication formats;
• an electrical connector for attaching said circuit to a wire for purposes of digital communication;
• two impedance matchers electrically connected between said electrical connector and said processor, said two impedance matchers have at least two electronically [and independently] selectable values of impedance wherein the at least two electronically selectable values of impedance comprise nominal values of 75 Ω, 100 Ω, and 120 Ω;
• control logic for electronically selecting one of said selectable values of impedance;
• and
• a programmable control processor, said control processor connected to said control logic for purposes of selecting impedance and also connected to said data processor for purposes of selecting a communication format.

A circuit for communicating digital data over a wire, said circuit comprising:

• first and second data processors, each of said processors programmed for use with digital data in at least two different communication formats;
• electrical connecting means for electrically attaching said first processor to a first wire and said second processor to a second wire for purposes of digital communication;
• a first impedance matcher electrically connected between said connecting means and said first processor and a second impedance matcher electrically connected between said connecting means and said second processor, said first and second impedance matchers each having at least two electronically and independently selectable values of impedance;
• control logic for electronically selecting one of said selectable values of impedance for each of said first and second impedance matchers;
• a programmable control processor, said control processor connected to said control logic for purposes of selecting impedance and also connected to each of said data processors for purposes of selecting a communication format.