Preemphasis, Termination, And Equalization - Xilinx LogiCORE IP Spartan-6 Getting Started Manual

Preemphasis, Termination, and Equalization

The Preemphasis, Termination, and Equalization screen (page 6) of the Wizard
(Figure
X-Ref Target - Figure 3-10
Table 3-12
Table 3-12: Preemphasis and Differential Swing
Option
Specifies the output pre-emphasis setting in 6.5% steps from 0% to approximately 45%. Selecting
Use TXPREEMPHASIS port enables the optional TXPREEMPHASIS configuration port to
dynamically set the pre-emphasis level.
Preemphasis Level
The PCI EXPRESS example uses the default setting of 000 (0%). See the Spartan-6 FPGA GTP
Transceivers User Guide for a table mapping TXPREEMPHASIS value settings to pre-emphasis
levels.
Specifies the differential swing level for the transmitter main driver in 100 mV steps from
approximately 300 mV to 1400 mV. Can also be set to zero. Selecting Use TXDIFFCTRL port
enables the optional TXDIFFCTRL configuration port to dynamically set the swing level.
Main Driver
Differential Swing
The PCI EXPRESS example uses the default setting 1001 (1110 mV). See the Spartan-6 FPGA GTP
Transceivers User Guide for a table mapping TXDIFFCTRL value settings to differential swing
levels.
Spartan-6 FPGA GTP Transceiver Wizard v1.8
UG546 (v1.8) December 14, 2010
3-10) allows you to set the preemphasis, termination, and equalization options.
Figure 3-10: Preemphasis, Termination and Equalization - Page 6
details the preemphasis and differential swing settings.
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Description
Generating the Core
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