Method and systems for use with an industrial controller
US5508909A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1994 |
| Grant date | Apr 16, 1996 |
| Priority date | — |
| Expiry date | Apr 26, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/323
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and system for generating a control program executable by an industrial controller, wherein a source program is displayed using a variable width ladder diagram. Instructions of a source program are received by a host computer, wherein the source program is compilable into the control program. A ladder diagram representative of at least one of the instructions of the source program is displayed on a display device. The ladder diagram comprises a graphical interconnection of schematic elements, at least one of which having a corresponding display width which is variable. The corresponding display width is varied in dependence upon the greater of a corresponding symbol display width and a corresponding label display width. A method and system for data communication with the industrial controller uses a hybrid error detection code. Each transmitted packet of data is augmented with either a Fletcher checksum code if the length of the packet is less than a predetermined packet length threshold, or a CCITT-16 cyclic redundancy check code if the length of the packet is greater than or equal to the predetermined packet length threshold.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.