Control system job recovery after a malfunction
US4521847A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 21, 1982 |
| Grant date | Jun 4, 1985 |
| Priority date | — |
| Expiry date | Sep 21, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/5012
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention is a multiprocessor control system that allows full job recovery after a machine power down or after a malfunction or software crash or temporary power outage. In particular, essential variables such as the state and status of the machine and the programmed job at the time of the malfunction are maintained in nonvolatile memory. This information is continually updated in nonvolatile memory. Once the control system has reset and reinitialized all the control elements after a malfunction, the control restores or downloads all the relevant variables in the nonvolatile memory to the various control elements to maintain status. In another embodiment, the essential variables are maintained in RAM locations in a master processor and saved for downloading to the control elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.