SOFTWARE_MONITOR

Published:2009/7/6 20:40:00 Author:May | From:SeekIC

Detects large percent-age of random faults, such as overflow conditions. Based on fact that part of program passes through reentry on predictable repeat basis. For each reentry, pulse is fed from CPU to input of ,, 74LS123 retriggerable mono MVBR. On each pass through program, programmer sets and then resets MVBR. Period of mono is made longer than longest normal time between programmed pulse outputs, to prevent false alarms. Any system fault that makes program repeat instructions endlessly or lose control will give false indication.-D. Brickner, Get a Watch-dog to Monitor Those Real-Time Operations, Kilobaud, April 1978, p 118-119.



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