公开(公告)号：DE2963075D1

公开(公告)日：1982-07-29

申请号：DE2963075

申请日：1979-09-24

Applicant: IBM

Inventor： DIEZ MARK FERNANDO ,  LEWIS DAVID OTTO ,  ROBINSON THOMAS SCOTT

IPC: G06F11/30 ,  G06F11/00 ,  G06F11/34 ,  G06F13/00

Abstract: In order to monitor non-uniform I/O device activity with low time overheads, data processing appparatus is provided iriicluding a hardware monitor including a memory array (4) having a location for each I/O device loaded with control data from the central processor at start I/O time. The monitor is driven by a free running ring (80) and maintains in the location for each I/O device an updated count of running time in terms of the output of an interval timer (76) until command end or other ordered clear. The monitor searches the array location cyclically, comparing the processor supplied data and the currently generated data, signalling the processor only when the two values are equal (or current exceed specified). Automatic house-keeping is provided for.