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 also 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 towards user side. One being the AXI4 -lite or AHB complaint interface for accessing through processor and other is simple general-purpose interface which can be used without the processor.