A memory system connected to another apparatus via a data crossbar, has a first memory, a second memory that forms a dual configuration together with the first memory, a first memory controller that transmits or receives data to be written into the first memory or data read out from the first memory to or from the other apparatus, a second memory controller that transmits or receives data to be written into the second memory or data read out from the second memory to or from the other apparatus, and a system controller that instructs the first memory controller and the second memory controller to read out, from the first memory and the second memory, data requested to be read out by the other apparatus if the system controller detects that any one of the first data crossbar and the second data crossbar being not capable of transmitting or receiving data.