Programmable controller with an operator messaging function
US5319783A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1991 |
| Grant date | Jun 7, 1994 |
| Priority date | — |
| Expiry date | Aug 13, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B19/052
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A programmable controller senses the status of input devices and controls the state of operating devices in accordance with a stored ladder logic control program. A memory of the programmable controller contains message data and data defining a set of expected transitions of the status of selected input devices. An instruction of the ladder logic initiates execution of a machine language message program which causes the programmable control to inspect the states of the selected input devices to determine whether an expected transition has taken place. When one of the expected transitions occurs, the message data and an identification of the selected input device are sent to a personal computer connected to the programmable controller. The personal computer uses the the data from the programmable controller to formulate an alphanumeric message which is presented to the operator on a display device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.