Xilinx LogiCORE IP Spartan-6, Getting Started Manual

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22 www.xilinx.com Spartan-6 FPGA GTP Transceiver Wizard v1.8
UG546 (v1.8) December 14, 2010
Chapter 3: Running the Wizard
Table 3-3 shows the options for the Common Settings. These options establish the shared
PMA PLL settings for both GTP transceivers in each pair.
3. Use the following tables to determine the line rate, encoding, decoding, and reference
clock settings available on this page.
Table 3-4 details the TX Settings options.
Table 3-3: Common Settings
Option Description
Target Line Rate
Line rate in Gb/s desired for the target design.
The PCI EXPRESS example uses 2.5 Gbps.
Reference Clock
Select from the list the optimal reference clock frequency to be provided
by the application.
The PCI EXPRESS example uses 125.0 MHz.
Table 3-4: TX Settings
Option Description
Line Rate
Set to the desired target line rate in Gbps. Can be independent of the receive
line rate. The line rate has option of selecting No_TX. This option disables all
the TX ports in the wrapper when selected.
The PCI EXPRESS example uses 2.5 Gbps.
Encoding
None Data stream is passed with no conversion.
None (MSB First)
Same as above but reorders bytes for applications expecting most significant
byte first.
8B/10B Data stream is passed to an internal 8B/10B encoder prior to transmission.
Data Path Width
8
Sets both the internal transmitter data path and the transmitter application
interface data path width to a single 8-bit byte.
10
Sets the internal transmitter data path width to a single 10-bit byte. If 8B/10B
encoding is selected, the transmitter application interface data path width will
be set to 8 bits. If 8B/10 encoding is not selected, the transmitter application
interface data path width is set to 10 bits.
16
Sets the internal transmitter data path width to a single 8-bit byte. Sets the
transmitter application interface data path width to two 8-bit bytes (16 bits).
20
Sets the internal transmitter data path width to a single 10-bit byte. If 8B/10B
encoding is selected, the transmitter application interface data path width will
be set to two 8-bit bytes (16 bits). If 8B/10B encoding is not selected, the
transmitter application interface data path width will be set to two 10-bit
bytes (20 bits).
32
Sets the internal transmitter data path width to a single 8-bit byte. Sets the
transmitter application interface data path width to four 8-bit bytes (32 bits).
40
Sets the internal transmitter data path width to a single 10-bit byte. If 8B/10B
encoding is selected, the transmitter application interface data path width will
be set to four 8-bit bytes (32 bits). If 8B/10B encoding is not selected, the
transmitter application interface data path width will be set to four 10-bit
bytes (40 bits).