Table 51: RX Equalizer Attributes
Attribute
Type
Description
CH[0/1]_RX_APT_CTRL_CFG2
16-bit
Reserved.
Bit Name
Address
Description
RXMODSEL
[3]
Receiver input modulation control.
0’b0
: PAM4 modulation.
0’b1
: NRZ modulation.
CH[0/1]_RX_APT_CFG27A[15:0]
16-bit
Adaptation loop freeze controls. Use the recommended
value from the Wizard.
Bit
Description
[15:13]
Reserved.
[12]
Enable to freeze current automatic gain
control (AGC) adapt value.
[11]
Enable to freeze current CTLE High
frequency loop (KH) adapt value.
[10]
Enable to freeze current CTLE Low
frequency loop (KL) adapt value.
[9]
Enable to freeze current Offset Cancelation
(OS) adapt value.
[8:5]
Reserved.
[4]
Enable to freeze current FFE Tap HM4 adapt
value.
[3]
Enable to freeze current FFE Tap HM3 adapt
value.
[2]
Enable to freeze current FFE Tap HM2 adapt
value.
[1]
Enable to freeze current FFE Tap HM1 adapt
value.
[0]
Adaptation freeze control. This bit must be
enabled to freeze the loops selected in
CH[0/1]_RX_APT_CFG27A, and
CH[0/1]_RX_APT_CFG27B. If this bit is set to
Low, all loops will be auto-adapting.
Chapter 4: Receiver
UG581 (v1.0) January 4, 2019
Virtex Ult GTM Transceivers
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