Xilinx Virtex UltraScale+ FPGAs - Page 102

Table 60: Pattern Checker Ports (cont'd)
Port Dir Clock Domain Description
CH[0/1]_RXPRBSPTN[3:0] In CH0_TXUSRCLK2 Receiver PRBS checker test pattern
control. Only these settings are valid:
4’b0000: Standard operation
mode (PRBS check is off)
4’b0001: PRBS-7
4’b0010: PRBS-9
4’b0011: PRBS-15
4’b0100: PRBS-23
4’b0101: PRBS-31
4’b0110: PRBS-13
After changing patterns, perform a
reset of the RX or a reset of the PRBS
error counter
(CH[0/1]_RXPRBSCSCNTRST) such that
the RX pattern checker can attempt to
reestablish the link acquired. No
checking is done for non-PRBS
patterns.
CH[0/1]_RXPRBSERR Out CH[0/1]_RXUSRCLK2 This non-sticky status output indicates
that PRBS errors have occurred. Only
use CH[0/1]_RX_PRBSERR to read the
precise bit error counts.
CH[0/1]_RXPRBSLOCKED Out CH[0/1]_RXUSRCLK2 Output to indicate that the RX PRBS
checker has been error free for
CH[0/1]_RX_PCS_CFG1[12:5] cycles after
reset. After being asserted High,
CH[0/1]_RXPRBSLOCKED does not
deassert until reset of the RX pattern
checker via a reset of the RX
(GTRXRESET, RXPMARESET, or
RXPCSRESET in sequential mode) or a
reset of the PRBS error counter
(CH[0/1]_RXPRBSCSCNTRST).
CH[0/1]_RXPRBSCNTSTOP
In CH[0/1]_RXUSRCLK2 Input control to stop the error counter.
The PRBS checker needs to restart the
error counter after a PRBS stop.
The following table denes the paern checker aributes.
Table 61: Pattern Checker Attributes
Attribute Type Description
CH[0/1]_TX_PCS_CFG1 16-bit Reserved.
Bit Name Address Description
RXPRBSERR_LOOPBACK [7] When this attribute is set to 1, the CH[0/1]_RXPRBSERR bit is
internally looped back to CH[0/1]_TXPRBSINERR of the same GTM
transceiver. This allows synchronous and asynchronous jitter
tolerance testing without worrying about data clock domain
crossing. When this attribute is set to 1b’0, CH[0/1]_TXPRBSINERR
is forced onto the TX PRBS.
Chapter 4: Receiver
UG581 (v1.0) January 4, 2019 www.xilinx.com
Virtex UltraScale+ GTM Transceivers 102
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