Integrated multi-port repeater having shared resources

A serial scan circuit for a repeater, comprising:

• a plurality of ports, each port asserting a carrier sense signal when receiving information;
• means, coupled to said plurality of ports, for storing a plurality of values identifying whether each port's carrier sense signal had been previously asserted;
• and
• means for polling said storing means and providing a serial signal derived from said plurality of values.

A method for providing carrier sense signals from a repeater, comprising the steps of:

• storing a plurality of values identifying whether each port of a plurality of ports of the repeater asserted a carrier sense signal in response to receipt of information;
• polling periodically each said stored plurality of values;
• and
• outputting a serial signal derived from said polled stored plurality of values.

A multi-port repeater, comprising:

• a first and a second port for receiving encoded information, each asserting a first and a second carrier sense signal, respectively, when receiving said encoded information;
• a decoder having a data input and an enable input for decoding information provided at said data input when an enable signal provided at said enable input is asserted;
• and
• a multiplexer circuit producing a logical sum of said first and second carrier sense signals as said enable signal and providing said enable signal to said enable input of said decoder.

A method of sharing a decoder in a multi-port repeater, comprising the steps of:

• producing a carrier sense signal from each port of a plurality of ports when receiving information;
• multiplexing each port's carrier sense signal to produce a logical sum of said plurality of port's carrier sense signals;
• and
• enabling a decoder to decode encoded information from said plurality of ports when said logical sum is asserted.

A serial scan circuit for a repeater, comprising:

• a plurality of ports, each port asserting a carrier sense signal in response to receipt of information;
• a polling circuit, coupled to said plurality of ports, for periodically sampling each said port during a sampling period;
• a plurality of latches, coupled to said plurality of ports, for storing a plurality of values identifying whether each port's carrier sense signal had been asserted during said sampling period;
• and
• a test port, coupled to said plurality of latches, for outputting a serial signal derived from said plurality of values.