A transmitting device and a receiving device are coupled together via an
interconnect. An electrical idle ordered set is received at the receiving
device power management unit after having been transmitted by the
transmitting device and received at the input pins of the receiving
device and moving through the receiver logic pipeline. At the time the
electrical idle ordered set has been recognized at the end of the
receiver logic pipeline, the power management unit checks for activity on
the interconnect. If there is no activity on the interconnect, then the
power management unit causes the receiving device to enter a low power
state where the receiver circuitry (input buffers) is turned off. If
there is activity on the interconnect when the electrical idle ordered
set is received at the power management unit, then the power management
unit does not cause the receiver circuitry to be turned off.