The present invention provides a method for accessing a secure digital (SD) card, which includes a voltage supply pin for receiving voltage supply from a host, at least one ground pin, a clock pin for receiving a clock signal from a host, a command pin for receiving a command from a host, and four data pins for writing data into the SD card or reading data from the SD card. The method includes receiving, via the command pin, an address extension command including a first address from a host, receiving, via the command pin, an access command including a second address from a host, and accessing, via the data pins, at least a memory location of the SD card indicated by a third address, which is a combination of the first address and the second address. The access command indicates an access operation to be performed on the SD card selected from: a single read operation, a single write operation, a multiple read operation, a multiple write operation and an erase operation.