| 摘要 |
PURPOSE:To generate and display a ladder circuit diagram by a programming device with a CRT which inputs a program to a programmable controller by removing the limit of a frequency of return and removing the limit of the number of series connection contacts. CONSTITUTION:When a ladder circuit diagram is displayed on a CRT screen 6, a contact is inserted between a connection point 7j and a coil 9a, and contacts 7k, 8f, 7l and 8g are inserted by using return origin symbols 10b and 10c, and return destination symbols 11b and 11c. Thus, the return origin symbols and return destination symbols are used repeatedly to remove the limit of the number of series connection contacts. Consequently, the high-level, complex ladder circuit diagram is generated and displayed. |
