The interconnect includes low-speed APB, top switch AXI, and the NPI.
- Low-speed bus clock for APB in PMC and PS programming interfaces
- Top-switch clocks for AXI interconnect
- NPI clock for memory mapped registers in NoC, DDRMC, AI Engine, and other integrated hardware
Low-speed Bus Clocks
The low-speed bus (LSBUS) clocks drive the APB programming interfaces.
Top Switch Interconnect Switch Clocks
The LPD_TOPSW_CLK clock frequency must always be set higher than the LPD_LSBUS_CLK clock frequency.
Recommended: Xilinx recommends that the LPD_TOPSW_CLK clock frequency is at least 1.5 times faster than the LPD_LSBUS_CLK.
The FPD_TOPSW_CLK clock frequency must always be set higher than the FPD_LSBUS_CLK clock frequency. This clock is used on the FPD main switch and the auxiliary FPD switch for AXI port interfaces.
Recommended: Xilinx recommends that the FPD_TOPSW_CLK clock frequency is at least 1.5 times faster than the FPD_LSBUS_CLK.
NPI Reference Clock
The NPI_REF_CLK is used to clock several blocks.
- NPI programming interfaces to the NPI register modules
- GTs in the PL
Because the NPI_REF_CLK is used by the GTs in the PL, its frequency must be set accurately to 300 MHz.
Note: The NPI_REF_CLK specification is in the Versal AI Core Series Data Sheet: DC and AC Switching Characteristics (DS957).