Tandem with Field Updates is a solution for UltraScale devices that allows designers to meet fast configuration needs and dynamically change the user application by loading a new bitstream over the PCIe link without the PCIe link going down. The solution uses Tandem Configuration to initially configure the device when the power is turned on, followed by Dynamic Function eXchange (DFX) of a predefined region in the FPGA. This allows the stage 1 bitstream to be locked in flash, with updates to that image are only required if the UltraScale Devices Gen3 Integrated Block for PCIe core characteristics or the I/O or clock management blocks in the configuration bank (bank 65) must change. Field Updates allows the user application, basically everything else in the design, to be dynamically reloaded as new features or functionality are needed.
Tandem with Field Updates is a specific, predefined use case of a more general Tandem + DFX solution. These two solutions (Tandem and DFX) are also supported in general in the same design, allowing you to partially reconfigure smaller and multiple regions within the user application.
After the UltraScale Devices Gen3 Integrated Block for PCIe core is generated, a sample design can be created that provides the template for the Tandem with Field Updates structure. This design shows the required structure, floorplan, properties, and scripts that can be adapted for your design. Follow this example to sort your design into two sections, mapping them to the two bitstream stages. The sample design is delivered in a scripted non-project mode, but project mode can be used as well.