Memory Slave Controller IP forms a bridge between the SD host and user interface, enabling the data transfer between each other. This IP will send the response to the SD host depending on the command issued and communicates with the user through a register interface for control and status. The Controller has two different variants depending on the availability of the processor on the user side. One is the AXI4 -lite or AHB-compliant interface for accessing the processor, and the other is a simple general-purpose interface that can be used without the processor.