Table 46: TX Configurable Driver Ports (cont'd)
Port Dir
Clock
Domain
Description
CH[0/1]_TXEMPPRE2[3:0] Input Async Transmitter pre-cursor 2 TX pre-emphasis control for channel 0.
The default is user specified. All listed values (dB) are typical
[4:0] dB (PAM4) dB (NRZ) Coefficient
Units
4’b0000
0.0 0.0 0
4’b0001
–0.3 –0.2 1
4’b0010
–0.7 –0.5 2
4’b0011
–1.1 –0.7 3
4’b0100
–1.5 –0.9 4
4’b0101
–1.9 –1.2 5
4’b0110
–2.3 –1.5 6
4’b0111
–2.7 –1.7 7
4’b1000
N/A –2.0 8
4’b1001
N/A –2.3 9
4’b1010
N/A –2.6 10
4’b1011
N/A –2.9 11
Notes:
1. The peak-to-peak differential voltage is defined when
CH[0/1]_TXEMPPRE = 5’b00000, and CH[0/1]_TXEMPPOST
= 4’b0000. Emphasis = 20log10(V
high
/V
low
) = |
20log10(V
low
/V
high
)|.
Chapter 3: Transmitter
UG581 (v1.0) January 4, 2019 www.xilinx.com
Virtex UltraScale+ GTM Transceivers 81