Read from a register that does not have all 0s as a default to verify that the interface is functional. See This Figure for a read timing diagram. Output s_axi_arready asserts when the read address is valid, and output s_axi_rvalid asserts when the read data/response is valid. If the interface is unresponsive, ensure that the following conditions are met:
• The lite_aclk inputs are connected and toggling.
• The interface is not being held in reset, and lite_aresetn is an active-Low reset.
• The main subsystem clocks are toggling and that the enables are also asserted.
• If the simulation has been run, verify in simulation and/or a debug feature capture that the waveform is correct for accessing the AXI4-Lite interface.