A device is provided that includes a first memory and a second memory and an accessing circuit. Actual addresses of the first memory and the second memory alternately correspond to reference addresses of a processing circuit. The accessing circuit is configured to perform the steps outlined below. A read command corresponding to a reference read address is received from the processing circuit to convert the reference read address to an actual read address of the first memory and the second memory. A first read data is read from a first one of the first memory and the second memory according to the actual read address and a second read data is prefetched from a second one of the first memory and a second memory according to a next first read address simultaneously.