| 摘要 |
PURPOSE:To attain the test designation of a storage device without using a package pin by setting a test flag to designate a test mode by the result of decoding the field of a microinstruction. CONSTITUTION:A next address generating circuit 1003 decodes the field to control a next microinstruction address and generates a next address and the microinstructions are successively read out of a storage device 1000 by this address. By the result of decoding the field of the microinstruction, the flag to designate the test mode is set to a register 1010. The test mode of the storage device 1000 is designated by the set of the test flag, the microinstructions in a designated address range are read out of the storage device 1000 and diagnosed, when invalidity is detected by an invalidity detecting circuit 1004, a selector 1015 is allowed to select a NOP signal and a parity check is made invalid. |
