| 摘要 |
PURPOSE:To perform the tracing of input/output operations, the logging of errors, etc. efficiently, by connecting a status recording device between a main storage device and a system bus when a predetermined status is generated. CONSTITUTION:When an error occurs, a central processing device issues a reading command for the response status to an input/output controller for the purpose of receiving the response of the input/output controller to obtain its contents. At this time, the response status is transmitted again on a data line 19, and the output of a condition setting/discriminating circuit 13 is transmitted to an address selector 12, and then, the signal of an address line 20 of a system bus 6 is suppressed, and the output of an address register 11 is outputted as an address of a main storage device. Thus, contents of the data line 19 (the status of an input/output device) are written in a prescribed address of the main storage device. |
