A first electronic device includes a first electronic circuit and a second electronic circuit. The first electronic device may include an internal communication link providing a signal path for conducting communication signals between the first electronic circuit and the second electronic circuit. An interface circuit may be operatively coupled to the internal communication link. The interface circuit may include an extremely high frequency (EHF) communications circuit configured to receive an EHF electromagnetic signal from another EHF communications circuit of a second electronic device. This EHF electromagnetic signal may enable the second electronic device to control or monitor the first electronic device.