ChipScope Pro Software and Cores User Guide
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UG029 (v14.3) October 16, 2012
ChipScope Pro Analyzer Features
•
Far-End PMA: The circuit originates and ends at some external channel endpoint (for
example, a piece of test equipment or another device) but passes through the part of
the GTP transceiver channel. For this GTP loopback mode, the signal comes into the
RX pins, passes through the PMA circuitry, and returns immediately to the TX pins.
•
Far-End PCS: The circuit originates and ends at some external channel endpoint (for
example, a piece of test equipment or another device) but passes through part of the
GTP transceiver channelGTP transceiver channel. For this GTP loopback mode, the
signal comes into the RX pins, passes through the PMA, through the PCS, back
through the PMA, and returns to the TX pins.
•
Far-End Fabric: The circuit originates and ends at some external channel endpoint (for
example, a piece of test equipment or another device) but passes through the entire
GTP transceiver channelGTP transceiver channel and related fabric logic. For this
GTP loopback mode, the signal comes into the RX pins, passes through the PMA and
PCS, through a shallow fabric-based FIFO, back through the PCS and PMA, and
finally returns to the TX pins.
The
Channel Reset
button resets the GTP transceiver channelGTP transceiver channel by
clearing and resetting all internal PMA and PCS circuitry as well as the related fabric
interfaces.
The
TX Polarity Invert
setting controls the polarity of the data sent out of the TX pins of the
GTP transceiver channel. To flip the polarity of the TX side of the GTP transceiver, check
the
TX Polarity Invert
box.
The
TX Bit Error Inject
button inverts the polarity of a single bit in a single transmitted
word. The receiver endpoint of the channel that is connected to this transmitter should
detect a single bit error.
The
TX Diff Output Swing
combo box controls the differential swing of the transmitter.
Change the value in the combo box to change the swing.
The
TX Pre-Emphasis
combo box controls the amount of pre-emphasis on the transmitted
signal. Change the value in the combo to change the emphasis.
The
RX Polarity Invert
setting controls the polarity of the data received by the RX pins of
the GTP transceiver channel. To flip the polarity of the RX side of the GTP transceiver,
check the
RX Polarity Invert
box.
The
RX AC Coupling Enabled
setting controls whether the built-in AC coupling
capacitors are enabled or not.
The
RX Termination Voltage
setting controls which supply is used in the RX termination
network.
The
RX Equalization setting
controls the internal RX equalization circuit.
BERT Settings
The
TX/RX Data Pattern
settings are used to select the data pattern that is used by the
transmit pattern generator and receive pattern checker, respectively. These patterns
include PRBS 7, 15, 23, and 31, and Clk 2x and 10x.
The
RX Bit Error Ratio
field contains the currently calculated bit error ratio for the GTP
transceiver channel. It is expressed as an exponent. For instance, 1.000E-12 means that one
bit error happens (on average) for every trillion bits received.
The
RX Received Bit Count
field contains a running tally of the number of bits received.
This count resets when the
BERT Reset
button is pushed.
