Browse Prior Art Database

Event Recorder

IP.com Disclosure Number: IPCOM000084793D
Original Publication Date: 1976-Jan-01
Included in the Prior Art Database: 2005-Mar-02
Document File: 2 page(s) / 56K

Publishing Venue

IBM

Related People

Faidley, VJ: AUTHOR [+4]

Abstract

Diagnostic data collection for data processing input/output devices is facilitated by using an addressable storage device as an event recorder and time stamp recorder, in which control signal changes can be stored along with the times of occurrence.

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Event Recorder

Diagnostic data collection for data processing input/output devices is facilitated by using an addressable storage device as an event recorder and time stamp recorder, in which control signal changes can be stored along with the times of occurrence.

In the figure, storage device 1, such as a half-word memory, is divided into two parallel sections with one of two bytes at each address reserved for recording event signals and the other byte at the same address reserved for recording clock time. Multiple input signals, for example from a printer, are connected through suitable gates to an input register 2 so that a particular signal plurality can be chosen for examination by appropriate commands at decoding circuit 3.

The set of control signals a, b or c from register 2 is gated through AND gate 4 into the scan data byte of the first address location of storage device 1, under control of the scan timing controls 5 and compare circuit 6. These controls also allow simultaneous recording of the triggers of a clock 7 through gate 8 to provide a time stamp.

The compare circuit 6 under control of clock 7 at frequent fixed intervals compares the stored scan data with that existing presently in input register 2. When an unequal compare signal is produced, it is effective through OR gate 9 at address controls 10 to activate the next successive address at storage device 1, and condition AND gate circuits 4 and 8 to record the new state of input register 2 with its corresponding clock time. Since the data signa...