发明授权
- 专利标题： Extended relay ladder logic for programmable logic controllers
- 专利标题（中）： 用于可编程逻辑控制器的扩展梯形图逻辑
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申请号： US915970申请日： 1997-08-21
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公开(公告)号： US5963446A公开(公告)日： 1999-10-05
- 发明人: Michael T. Klein , William Perry Su , Richard Leroy Mahn , Per-Ola Gustav Forsgren
- 申请人： Michael T. Klein , William Perry Su , Richard Leroy Mahn , Per-Ola Gustav Forsgren
- 申请人地址： MI Ann Arbor
- 专利权人： Steeplechase Software, Inc.
- 当前专利权人： Steeplechase Software, Inc.
- 当前专利权人地址： MI Ann Arbor
- 主分类号： G05B19/05
- IPC分类号： G05B19/05 ; G05B11/01
摘要：
A digital computer implemented software system is provided for programming industrial logic controllers using a software package of the type utilizing relay ladder logic to represent control programs. The control program is executable by the controller to control the operation of one or more industrial devices. Using relay ladder logic, the control programmer is provided with a system to replace a coil with an ACTION block containing at least one complex expression. When the left side of the ACTION block is energized, the expression is evaluated. In a further embodiment, the programmer is able to replace a contact with a DECISION block containing a Boolean expression. When the left side of the DECISION block is energized, the Boolean expression is evaluated. If the expression evaluates as TRUE, the right side of the DECISION is energized.