A semiconductor apparatus according to an aspect of the present invention includes first and second bus-interface circuits, a first memory core connected to the first bus-interface circuit through a first data bus, the first memory core being connected to a first access control signal output from the first bus-interface circuit, a second memory core connected to the second bus-interface circuit through a second data bus, and a select circuit that selectively connects one of the first access control signal and a second access control signal output from the second bus-interface circuit to the second memory core.