Category: Walkie Talkie
tool:-
Device: Arria® 10

Please refer to the device datasheet (hereafter Intel® Arria® 10 Device Datasheet) for the Run Length specification.
In addition, the conditions for CDR to transition to LTR -> LTD mode are as follows, so if this is violated, it will transition to LTD -> LTR mode.

(Reference) Intel® Arria® 10 Device Datasheet
https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/hb/arria-10/ug_arria10_xcvr_phy.pdf
(CDR Lock Modes item)

Please select Refclk required for CDR from the pull-down list.
Although it depends on the protocol, it is basically used by connecting the input reference clock used by the TX PLL.