Ports And Attributes - Xilinx Virtex-6 FPGA User Manual

LOSS_OF_SYNC state. The RX_LOS_THRESHOLD entry in
settings for this attribute.
The LOS state machine allows the error count in the SYNC_ACQUIRED state to decrease
over time, so that sparse errors are eventually discarded. The rate that the error count is
decreased is controlled by the RX_LOS_THRESHOLD and RX_LOS_INVALID_INCR
attributes, as defined in

Ports and Attributes

Table 4-36
Table 4-36: RX Loss-Of-Sync State Machine Ports
Port Dir
RXLOSSOFSYNC Out
Table 4-37
Table 4-37: RX Loss-Of-Sync State Machine Attributes
Attribute
RX_LOS_INVALID_INCR
RX_LOS_THRESHOLD
RX_LOSS_OF_SYNC_FSM
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Virtex-6 FPGA GTX Transceivers User Guide
UG366 (v2.5) January 17, 2011
Table 4-37.
defines the RX Loss-of-Sync State Machine ports.
Clock Domain
RXUSRCLK2 FPGA status related to byte stream synchronization. The meaning
depends on the state of the RX_LOSS_OF_SYNC_FSM attribute.
If RX_LOSS_OF_SYNC_FSM = TRUE, this output reflects the state
of an internal Loss-of-Sync FSM as follows:
[1] = 1: Sync lost due to either sequence of invalid characters or
reset
[0] = 1: In the resync state due to a channel bonding sequence or
realignment
If RX_LOSS_OF_SYNC_FSM = FALSE, this output presents the
following information about incoming data:
[1] = 1: Received data is not an 8B/10B character or has a disparity
error
[0] = 1: Channel bonding sequence detected in data
defines the RX Loss-of-Sync State Machine attributes.
Type
Integer Defines the number of valid characters required to cancel out the appearance of
one invalid character for the purpose of loss-of-sync determination. Valid
settings are 1, 2, 4, 8, 16, 32, 64, and 128.
Integer When divided by RX_LOS_INVALID_INCR, defines the number of invalid
characters required to cause an FSM transition to the sync lost state. Valid
settings are 4, 8, 16, 32, 64, 128, 256, and 512.
Integer RX_LOSS_OF_SYNC_FSM defines the behavior of the RXLOSSOFSYNC[1:0]
outputs.
FALSE (default): RXLOSSOFSYNC[1] goes High when invalid data (not in
table or disparity error) is found in 8B/10B decoding. RXLOSSOFSYNC[0]
goes High when a channel bonding sequence has been written into the RX
elastic buffer.
TRUE: Loss of sync FSM is in operation and its state is reflected on
RXLOSSOFSYNC[1].
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RX Loss-of-Sync State Machine
Table 4-37
Description
Description
shows the valid
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