Each of the four (snickerdoodle one) or five (snickerdoodle black) FPGA connectors has 12x 100ohm differential pairs routed out in length-matched groups of six.

See pages 31-33 of the snickerdoodle schematics.

Note: A 2.5V VCCO_xx supply will need to be provided to the I/O banks where the LVDS I/O standard is to be used (LVDS_25 I/O attribute setting).