Description; Enabling Comma Alignment; Configuring Comma Patterns - Xilinx Virtex-5 RocketIO GTP User Manual

Chapter 7: GTP Receiver (RX)
Table 7-21: RX Comma Alignment and Detection Attributes (Continued)
Attribute
PCOMMA_DETECT_0
PCOMMA_DETECT_1
RX_SLIDE_MODE_0
RX_SLIDE_MODE_1

Description

Enabling Comma Alignment

To enable the comma alignment block, the RXCOMMADETUSE port is driven High.
RXCOMMADETUSE is driven Low to bypass the block completely for minimum latency.

Configuring Comma Patterns

To set the comma pattern that the block searches for in the incoming data stream, the
MCOMMA_10B_VALUE, PCOMMA_10B_VALUE, and COMMA_10B_ENABLE
attributes are used. The length of the commas depends on the INTDATAWIDTH of the tile
(see
masks each of the comma values to allow partial pattern matching.
Figure 7-12
wildcarded comma for a 10-bit internal comma.
If COMMA_DOUBLE is TRUE, the MCOMMA and PCOMMA patterns are combined so
that the block searches for two commas in a row. The number of bits in the comma depends
on INTDATAWIDTH (see
commas are combined when COMMA_DOUBLE is TRUE.
152
Control raising of RXCOMMADET on comma plus.
FALSE: Do not raise RXCOMMADET when comma plus is detected.
TRUE: Raise RXCOMMADET when comma plus is detected. (This setting does
not affect comma alignment.)
Selects between sliding in the PMA or in the PCS.
PMA.
"Shared PMA PLL," page
shows how a COMMA is combined with COMMA_ENABLE to make a
MCOMMA_10B_VALUE
or
PCOMMA_10B_VALUE
0101111100
0001111111
COMMA_10B_ENABLE
Figure 7-12: Comma Pattern Masking
"Shared PMA PLL," page
MCOMMA_10B_VALUE
Figure 7-13: Extended Comma Pattern Definition
www.xilinx.com
Description
Legal values are PCS (default) and
60). Figure 7-12 shows how the COMMA_10B_ENABLE
60).
PCOMMA_10B_VALUE
Virtex-5 RocketIO GTP Transceiver User Guide
Pattern required
for comma detection
(x = don't care)
xxx1111100
UG196_c7_12_092606
Figure 7-13 shows how the
UG196_c7_13_092606
UG196 (v1.3) May 25, 2007
R