| 摘要 |
PURPOSE:To execute a test without inputting a microprogram from an external part by automatically using the specified part of the microprogram during normal operation as the program for test. CONSTITUTION:At a normal operating time, a value, which reads the contents of a microprogram ROM4 from an address 3 to be outputted from an address register 2, is outputted from a multiplexer 19 as the microprogram. On the other hand, when a test terminal 10 is made active, an inputted address 11 for test is set to an address register 12. A microprogram 18 for test is set to a RAM17. Here, when coincidence between addresses 3 and 13 is detected in a comparator 14, a comparator output 15 goes to be active and a microcode 16 for test is outputted through the multiplexer 19. Then, the test is executed. |
