The SOM communicates with the RF slice using the I2C and the SPI by controlling buffers on these lines. Only one slice can be communicated at a time. The power supply control and monitoring for each slice is handled by the power supply management unit (PMU) and is controlled by the PS I2C through two multiplexers.
The first figure in this section provides a graphical view of the I2C connectivity tree. The second figure provides a more detailed graphical view of connected components on the XRF4 baseboard with associated PS I2C memory map address for access by the RF controller firmware (running on the Kria SOM PS). The third figure shows the connectivity and control for the PL I2C bus for this kit.
The following figure shows the SPI connectivity and control tree. Only a single slice's SPI can be communicated at a time using the 9-bit I2C_SPI_MOD_SEL signal.
The following figure shows the GPIO signal connectivity to the RF slices and auxiliary GPIO connector. These signals are controlled through RF controller firmware.