<Error message>
Error (170084): Can't route signal "xxxx~input" to atom "xxxx~output"

Category: Specifications
Tools: Quartus® Prime
Device: Cyclone® IV


A connection from REFCLK to the Clock Control Block is not possible.

(reference)
Cyclone IV Device Handbook, Volume 2
https://www.intel.com.au/content/dam/www/programmable/us/en/pdfs/literature/hb/cyclone-iv/cyiv-5v2.pdf
(Notes to Figure 1–26: in Input Reference Clocking)

--excerpt--
(2) "The REFCLK[1..0] and REFCLK[5..4] pins are dual-purpose differential REFCLK or DIFFCLK pins that reside in
banks 3B and 8B respectively.
For more details, refer to the Clock Networks and PLLs in Cyclone IV Devices chapter."