| 摘要 |
PURPOSE:To share a memory with a main processor without the provision of a specific control circuit, by executing the diagnosis of an input and output controller, through the transfer of a diagnostic program from the input and output diagnostic controller to a vacant area of a local memory. CONSTITUTION:A main processor 21, an input and output controller 22, and an input and output diagnostic controller 31 are connected with input and output bus interface lines 21a, and the controller 31 is provided with a run/stop circuit 39 stopping the program execution and running of a local processor 24 of the co controller 22. Further, a memory address reading circuit 35 reading the memory address of a local memory 23 executed with the processor 24 in the next timing is provided. A processor 32 of the controller 31 is connected with a DMA controlling circuit 34 with circuits 35, 39, the circuit 34 transfers a diagnostic program to a vacant area of the memory 23 via the line 21a and executes the diagnosis of the controller 22. |
