7. User Diagnostics
NetXen, Inc.
Intelligent NIC Getting Started Guide — NDA Required
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7.2.4
Internal Loop-Back Test
In this test the user diagnostic utility sets the Ethernet core (MAC) to perform a loopback
operation. The utility sends packets to itself, then compares the contents of the packets to
verify that the sent and received values are the same. No external hardware is required
for the internal loopback test.
7.2.5
External Full Duplex Loop-Back Test
For CX4 applications, an external module is required to connect the four transmit lanes to
the four corresponding receive lanes. This module must contain all of the associated
handshake signals required to redirect the four transmit lanes to the four receive lanes. In
this test the utility sends packets to itself through the optical transmit lane, reads the
contents on the receive lane, then compares the contents of the packets to verify that the
sent and received values are the same.
For XFP applications, an 850 nm multimode cable with LC connectors is required to
externally connect the transmit lane to the receive lane.
7.2.6
Link Test
This test reports whether the link is up or down and also checked the carrier detect on the
PHY.
7.2.7
All Tests
This option runs all of the above tests using a single command.
