Inhibit and status indication apparatus/cicuit

摘要

A medium attachment unit (MAU) is provided with a combined function override and status indication for a link test feature. A link integrity status feature is employed by MAU's to establish that the network is operational. The link test is performed by supplying test pulses over the network. Older devices which do not supply the necessary test pulses can cause newer devices to artificially detect a failure since they do not receive the test pulses.

The MAU disclosed herein is provided with a means for disabling the internal link test receive function while allowing transmit and receive functions of the MAU to remain operational. Idle link pulses are still generated irrespective of whether or not the test receive function is disabled. In one example, a pin on an IC package may be held at a particular level to activate the disable function. When the disable function is not active, the same pin may be used to drive an LED device for indicating the operational status of the apparatus.