| 摘要 |
PURPOSE:To facilitate the change of instruction data and to eliminate the restriction of a test item due to the capacity by changing the test ROM of a single chip microcomputer from a mask ROM to a RAM. CONSTITUTION:A RAM 5 capable of writing arbitray instruction data from a port at the time of test mode is provided, a selective circuit 8 for selecting the data of the RAM 5 instead of the data of a user ROM 2 and outputting them to an instruction decoder circuit 7 is provided and a test mode setting circuit 6 for executing control at the time of test mode is provided on the testing circuit for executing an operation confirmation by other instruction than that of the user ROM 2 of a single chip microcomputer. In such a manner the test of different items can by executed many times without minding the restriction of the capacity by the same sample. |
