AUTOMATIC CROSSOVER SYSTEM FOR A MEDIA DEPENDENT INTERFACE WITH HYSTERESIS

摘要

An automatic cross-over system (figure 3C) for a media dependent interface (MDI, 122 and 122') in a network device (100) includes a cross-over switch (140) interconnected between the media connector (MDI, 122 and 122') and the receiver (RX, 124) and transmitter (TX, 126). The cross-over switch (140) is configured to include at least two positions wherein: the first position connects a first signal path (144') to the receiver (RX, 124') and the second signal path (146') to the transmitter (TX 126'). The receiver (RX) is adapted for establishing a network connection over either signal path and for generating link established signals indicating whether a good link or network connect is established (128, figure 3A). The receiver (RX, 124) is adapted for determining whether a connection or link is established by determining whether a valid signal is present at the beginning and end of a timer cycle. The control logic (150) which receives the link established signal (128, figure 3A) and generates a switch control signal (142, figure 3A) for controlling the position of the cross-over switch (140).