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Virtex-5 RocketIO GTP Transceiver User Guide
UG196 (v1.3) May 25, 2007
Appendix A:
MGT to GTP Transceiver Design Migration
R
Serialization
As in Virtex-4 devices, Virtex-5 GTP transceivers serialize and send the least significant
byte first. Virtex-II Pro devices send the most significant byte first.
Defining Clock Correction and Channel Bonding Sequences
The bit definitions of the CLK_COR_SEQ and CHAN_BOND_SEQ have changed to
support more encoding functionality.
illustrates the differences.
RXSTATUS Bus
Several buses have changed over the FPGA generations to improve the information that is
indicated.
shows the migration from Virtex-II Pro to Virtex-5 devices.
Pre-emphasis, Differential Swing, and Equalization
The differential signaling techniques are more robust in recent Xilinx transceivers. The
Virtex-5 GTP transceiver adds ports to control TX characteristics to simplify
reconfiguration.
shows the migration of attributes from Virtex-II Pro and
Virtex-4 MGTs to Virtex-5 GTP transceivers.
Table A-11:
CLK_COR_SEQ and CHAN_BOND_SEQ Sequences
Bit Definition
Virtex-II Pro
MGT
Virtex-4
MGT
Virtex-5 GTP
Transceiver
8B/10B encoded definition
00110111100
(1)
00110111100
(2)
10-bit literal value
10011111010
(1)
10011111010
(2)
64B/66B encoding (sync character)
N/A
1XX
(sync header)
N/A
8-bit literal value (for 64B/66B and other encodings)
N/A
1XX
(8-bit data)
N/A
Notes:
1. Defines K28.5.
2. Defines K28.5 and depends on CLK_COR_8B10B_DE (plus all 10 bits are defined).
Table A-12:
Status Bus Changes
Description
Virtex-II Pro
MGT
Virtex-4
MGT
Virtex-5 GTP
Transceiver
(1)
Indicates channel bonding complete
CHBONDONE
(2)
RXSTATUS[5]
RXCHANISALIGNED
Indicates status bus is status, data, event
N/A
RXSTATUS[4:3]
RXSTATUS[2:0]
Indicates channel bonding or clock correction
pointers change
RXCLKCORCNT
RXSTATUS[2:0]
RXCHANREALIGN
Indicates that an RX buffer has
underflow/overflow
RXBUFSTATUS[1]
RXBUFERR
RXBUFSTATUS[2:0]
Notes:
1. Signal optimization settings are independent between both GTP transceivers of a GTP_DUAL tile. GTP0 is indicated by the suffix
“0” after the signal name, and GTP1 is indicated by the suffix “1” (for example, RXENEQB0 or RXENEQB1).
2. RXCLKCORCNT must go to
3'b101
before channel bonding is complete.