AUI to twisted pair loopback

Claim 1

A Medium Attachment Unit ("MAU") for implementing a first and second loopback mode in a computer network environment, comprising: a first and second input port; a first and second output port; means, coupled to said first and second input ports and said first and second output ports, for detecting the simultaneous transmission of a first signal received from said first input port for transmission to said second output port, and a second signal, received from said second input port for transmission to said first output port, and asserting a collision signal; means, responsive to said collision signal, for disabling said simultaneous transmission of said first and second signals; means, coupled to said simultaneous transmission detecting means and responsive to a third signal, for enabling the loopback modes; means, coupled to said enabling means, for implementing the first loopback mode when a fourth signal is asserted, otherwise; said implementing means implementing the second loopback mode when said fourth signal is negated; wherein said third and fourth signal are provided to the MAU from a source other than one of said first and second input ports; and wherein said disabling means is responsive to an assertion of said third signal to prevent said disabling means from disabling said simultaneous transmission of said first and second signals and wherein said first loopback mode directs said first signal from said first input port to said first output port and said second signal from said second input port to said second output port, and said second loopback mode directs said first signal from said first input port to said second output port and said second signal from said second input port to said first output port.

Claim 2

A Medium Attachment Unit ("MAU") for implementing a first and second loopback mode in a computer network environment, comprising: a first and second input port; a first and second output port; means, coupled to said first and second input ports and said first and second output ports, for detecting the simultaneous transmission of a first signal received from said first input port for transmission to said second output port, and a second signal, received from said second input port for transmission to said first output port, and asserting a collision signal; means, responsive to said collision signal, for disabling said simultaneous transmission of said first and second signals; means, coupled to said simultaneous transmission detecting means and responsive to a third signal, for enabling the loopback modes; means, coupled to said enabling means, for implementing the first loopback mode when a fourth signal is asserted, otherwise; said implementing means implementing the second loopback mode when said fourth signal is negated; wherein said third and fourth signal are provided to the MAU from a source other than one of said first and second input ports; and wherein said disabling means is responsive to an assertion of said third signal to prevent said disabling means from disabling said simultaneous transmission of said first and second signals and wherein said first loopback mode directs said first signal from said first input port to said first output port and said second signal from said second input port to said second output port, and said second loopback mode directs said first signal from said first input port to said second output port and said second signal from said second input port to said first output port.

Claim 3

A Medium Attachment Unit ("MAU") for implementing a first and second loopback mode in a computer network environment, comprising: a first input port for receiving a first data packet; a second input port for receiving a second data packet; a first output port for transmitting a first output data packet; a second output port for transmitting a second output data packet; a first control port for receiving a first control signal; a second control port for receiving a second control signal; first data packet routing means, coupled to said first input port, for routing said first data packet to said first output port when said first control signal is asserted, otherwise, said first packet routing means routing said first data packet to said second output port; second data packet routing means, coupled to said second input port, for routing said second data packet to said second output port when said first control signal is asserted, otherwise, said second packet routing means routing said second data packet to said first output port; means, coupled to said first and second input ports and said first and second output ports, for detecting a collision between said first data packet and said second data packet and asserting a collision signal; and means, coupled to said collision detecting means, for disabling said collision detecting means when said second control signal is asserted to said second control port.

Claim 4

A Medium Attachment Unit ("MAU") for implementing a first and second loopback mode in a computer network environment, comprising: a first input port for receiving a first data packet; a second input port for receiving a second data packet; a first output port for transmitting a first output data packet; a second output port for transmitting a second output data packet; a first control port for receiving a first control signal; a second control port for receiving a second control signal; first data packet routing means, coupled to said first input port, for routing said first data packet to said first output port when said first control signal is asserted, otherwise, said first packet routing means routing said first data packet to said second output port; second data packet routing means, coupled to said second input port, for routing said second data packet to said second output port when said first control signal is asserted, otherwise, said second packet routing means routing said second data packet to said first output port; means, coupled to said first and second input ports and said first and second output ports, for detecting a collision between said first data packet and said second data packet and asserting a collision signal; and means, coupled to said collision detecting means, for disabling said collision detecting means when said second control signal is asserted to said second control port.