| 摘要 |
PURPOSE:To improve the efficiency of maintenance, diagnosis, etc., by stopping a CPU only at the time of access from a previously specified access origin device to a specified address when there are plural access origin devices. CONSTITUTION:When the function of stopping address comparison is required as a result of diagnosing operation, etc., the unit machine number of an access origin device to be investigated is set in a comparison machine number register 5 externally and memory address information on a device to be stopped is set in a comparison address register 6. Further, a comparison significance signal line 9 is turned on. For access to a main storage device from a central processor 1 and input/output devices 2-1-2-n, machine number information and memory address information on a common bus are compared by a comparing circuit 7 with the contents of the comparison machine number register 5 and comparison address register 6. When both unit machine numbers and memory addresses coincide with each other, a central processor stop indication line 8 is turned on and the central processor 1 stops operating. |
