The following figure shows the XRF4 power-on sequence. The XRF4-RFBB receives a 12 V DC input power supply from the ZCU RFMC 2.0 connector or the onboard Molex DC connector as explained in XRF4-RFBB.
After power-on, the XRF4-RFBB supplies 5 V power to the AMD Kria™ K26 SOM board, which turns on status LEDs to display a successful power supply to the SOM PS and PL. The SOM starts booting PetaLinux from the boot image located on the SD card on the XRF4-RFBB. At successful boot, PetaLinux turns on the XRF4 INIT LED located on the XRF4-RFBB. PetaLinux acquires an IPv4 IP address if connected to the router or to a fixed IP address (10.10.1.7) if connected in a P2P setup to a host PC.
A start-up script starts the main XRF4 application, which exposes the XRF4 control APIs
to Pyro based server. A Pyro client application (MATLAB based) located on
the host PC controls the XRF4 system by communicating with the Pyro server. The IP
address used by the Pyro server is read from the Linux console over UART or can also be
acquired from a known scratch address (0xa0020028) by an SPI controller
inside ZCU DFE system.