Verifying communication lanes by individually disconnecting transmit wires by wire polarity

A system comprising:

• an integrated circuit having transmit circuitry and receive circuitry;
• the transmit circuitry coupled to a plurality of full duplex channels, each of the plurality of full duplex channels including a first transmit wire of a first polarity and a second transmit wire of a second polarity, each of the transmit wires having an in-line switch to functionally disconnect the corresponding wire;
• and
• data link layer components that control activation of the in-line switches to functionally disconnect all of the transmit wires of a first polarity for a first receive detection, to deactivate the switches after the first receive detection, to functionally disconnect all of the transmit wires of a second polarity for a second receive detection.

One or more non-transitory machine-readable media having program code stored therein, the program code to:

• activate first switches in each full duplex channel of a link coupling integrated circuits,
• wherein each full duplex channel includes a pair of transmit wires and a pair of receive wires, each pair of wires having a first wire of a first polarity and a second wire of a second polarity for differential signaling,
• wherein the first switches are in the first wires of the transmit wires;
• wherein activation of the first switches functionally disconnects the first wires;
• initiate a first receive detection on the link;
• associate a failure in the first receive detection with the second polarity;
• deactivate the first switches;
• activate second switches in each full duplex channel of the link,
• wherein the second switches are in the second wires of the transmit wires;
• wherein activation of the second switches functionally disconnects the second wires;
• initiate a second receive detection on the link;
• and
• associate a failure in the second receive detection with the first polarity.