Semiconductor memory, system, operating method of semiconductor memory, and manufacturing method of semiconductor memory

A plurality of memory blocks includes real memory cells and redundancy memory cells, are accessed independently during a normal operation mode, and are accessed simultaneously during a test mode in order for common data to be written to the plurality of memory blocks. A block control unit selects the plurality of memory blocks irrespective of a block address signal in order to execute a compression test. During the test mode, a redundancy access unit simultaneously accesses the redundancy memory cells of the plurality of memory blocks when a forced redundancy signal supplied to a block address terminal indicates first level. Therefore, the redundancy memory cells of the plurality of memory blocks may simultaneously access and test without providing any special terminal. As a result, before a defect is relieved, an operation test of the redundancy memory cells may efficiently execute, which may shorten the test time.