To provide available device resources as much as possible by narrowing down a fault place and separating minimum faulty devices.

When a fault detection circuit 4A0 monitors a signal from a crossbar switch 5 and detects a fault between networks, it notifies the a fault information collection circuit 490 of the fault. The circuit 490 collects the transfer source node number of fault data and notifies a test execution circuit 480 of fault occurrence and the transfer source node number. The circuit 480 transmits a test execution request to an interruption control circuit 450, and the circuit 450 transmits an interruption signal to a CPU 20. Then, the CPU 20 instructs an operation decoding circuit 440 to transfer a test pattern from the transfer source node to a different transfer destination. The instruction is transferred to the switch 5 through a command transmission circuit 470 and an SW write circuit 420.