Virtex-5 RocketIO GTP Transceiver User Guide
199
UG196 (v1.3) May 25, 2007
Description
R
Far-End PCS Loopback
This mode uses an external source for generating and checking the test data. The loopback
occurs in the PCS section and the received data is presented to the user logic.
The transmit data of the user logic is not transmitted when this mode is activated. This
mode is a PCI Express compliant loopback mode that echoes the received data back to the
sender.
illustrates this configuration.
Figure 9-5:
Far-End PCS Loopback
Far-End GTP
UG196_c9_05_082906
RX-PMA
RX-PCS
TX-PMA
TX-PCS
Parallel
Parallel
Serial
Serial