The GTH transceiver has very specific reset requirements as described in the
UltraScale
Architecture GTH Transceivers User Guide (UG576). The GTH transceiver requires
careful coordination of resets of the PLLs, GTH transceiver resets (gttxreset and gtrxreset).
Such coordination is simplified when the GTH transceiver is generated using the UltraScale FPGAs Transceiver Wizard with the clocking
network with the reset controller helper blocks enabled. The reset controller helper
block handles the complicated GTH transceiver reset sequence. The control module
supplied with this application note handles the reset assertions for all UHD-SDI core
configuration updates to ensure proper operation of the GTH transceiver.