Patent ID: 6694394
Filing Date: 2004-02-17
Classification: G06F,Y02D

Abstract:
A MAC comprising:an input port; a pullup coupled to the input port to provide a low impedance path to a power rail having a HIGH voltage when switched ON; an input buffer having an output port and an input port connected to the MAC input port; and a finite state machine to sample the input buffer's output port and to switch the pullup ON and OFF in response to a Reset signal generated by the MAC; wherein in response to the Reset signal the finite state machine switches ON the pullup and samples the input buffer's output port for a first time interval to determine whether during the first time interval the input port (i) is substantially at the HIGH voltage, (ii) is substantially at a LOW voltage distinct from the HIGH voltage, or (iii) after a second time interval less than the first time interval periodically cycles between the HIGH and LOW voltages.