| 摘要 |
PURPOSE:To quickly perform the I/O check of an I/O control part by hardware without changing software of a CPU to one for special test by comparing the output of a designated I/O circuit with the output selected from test data. CONSTITUTION:Data from a CPU bus 3 and data from a reference data generation part 40 which selects 1 to n pieces of test data by a selector 12 are switched by a selector 13. The address from the CPU bus 3 and the address from an address generation part 30 which divides the frequency of the output signal of an oscillator 12 with a counter 11 and generate address data are switched by a selector 14. A data comparator 19 compares input data from selectors 17-1 to 17-m with data from the reference data generation part 40, and when different data are inputted, a latch signal is outputted to a FIFO 18 to take in and preserve the address at this time from the address generation part 30. |
