Table 71: RX Interface Ports (cont'd)
Port
Dir
Clock Domain
Description
RXUSRCLK
In
Clock
This port is used to provide a clock for the internal RX
PCS datapath.
RXUSRCLK2
In
Clock
This port is used to synchronize the interconnect logic
with the RX interface. This clock must be positive-edge
aligned to RXUSRCLK.
The following table defines the TX interface attributes.
Table 72: RX Interface Attributes
Attribute
Type
Description
CH[0/1]_RX_PCS_CFG0
16-bit
Reserved.
Bit Name
Address
Description
RX_DATA_WIDTH
[2:0]
Sets the bit width of the RXDATA port. When FEC is enabled,
RX_DATA_WIDTH must be set to 160:
0x0: 64-bit fabric mode.
0x1: 80-bit fabric mode.
0x2: 128-bit fabric mode.
0x3: 160-bit fabric mode.
0x4: 256-bit fabric mode.
RX_INT_DATA_WIDTH
[4:3]
Controls the width of the internal RX PCS datapath. 80-bit
internal datapath must use with 80- or 160-bit fabric width;
128-bit internal datapath must use with 128- or 256-bit
fabric width; 64-bit internal datapath must use with 64 or
128-bit fabric width:
0x0: 64-bit internal datapath mode.
0x1: 80-bit internal datapath mode.
0x2: 128-bit internal datapath mode.
GEN_RXUSRCLK
[14]
Automatically generates RXUSRCLK from RXUSRCLK2, only
applicable when fabric datapath width is the same as the
internal datapath width:
0x0: Disables automatic RXUSRCLK generation from
RXUSRCLK2.
0x1: Enables automatic RXUSRCLK generation from
RXUSRCLK2.
CH[0/1]_A_CH_CFG0
16-bit
Reserved.
Bit Name
Address
Description
RX_FABINT_USRCLK_FLOP
[1]
Determines if port signals are registered again in the
RXUSRCLK domain after being registered in the RXUSRCLK2
domain. This attribute only applies if the RX internal
datapath width is the same as the RX interface width,
otherwise this attribute is ignored. Use the recommended
value from the Wizard.
0x0: Bypass RXUSRCLK flip-flops.
0x1: Enable RXUSRCLK flip-flops.
Chapter 4: Receiver
UG581 (v1.0) January 4, 2019
Virtex Ult GTM Transceivers
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