Bank 65 contains dedicated and dual-mode configuration pins. Tandem Configuration can use many of these pins, including the dedicated PCIe reset pin (PERSTN) in UltraScale devices, and many configuration pins, such as EMCCLK, CSI_B and address and data pins for wider interfaces.
IMPORTANT: AMD advises Tandem Configuration users to avoid using bank 65 for design applications, especially when using Tandem PROM, to avoid complications because the programming bitstream is split into two stages. Specifically, IP cores built by the Memory Interface Generator (MIG) must not use bank 65 I/O . This ensures that IP can remain completely within stage 2, and avoid complications with its embedded I/O and demanding timing constraints.
To see the pins required for your desired configuration mode, see the configuration diagrams in the UltraScale Architecture Configuration User Guide (UG570) [Ref 7] .