| 摘要 |
PURPOSE:To easily investigate the cause of a fault by outputting an error signal to the bus interface device unless a check code is discrepant or when a no- resource address is detected. CONSTITUTION:An input/output device 6 when accessing a main storage device 4 outputs an address and the check code of the address to an input/output bus 2. A bus interface device 5 calculates the check code by an address calculating circuit from the address received from the input/output bus 2 and sends the check code to an address comparing circuit. Further, the check code on the input/output bus 2 is inputted to the address comparing circuit. The address comparing circuit 2 compares the two check codes with each other, and the bus interface device 5 judges that an error occurs to the address unless the check codes match each other and outputs an error signal to the input/output bus 2 through an error signal generating circuit to inform the input/output device 6 of the error. |
