| 摘要 |
PURPOSE:To detect accurately the time of the occurrence of the state change of a digital signal which is inputted by the processing time or the like of a program, by providing a storage circuit in an input module device. CONSTITUTION:When an inputted digital input signal S1 is changed, the state change of the digital signal is detected by a detecting circuit 3 of an input module 2', and an external interrupting signal is transmitted from an interrupting signal generating circuit 4 to a microprocessor 1 through a microprocessor bus 6. A time signal S2 at this time is stored in a storage circuit 7. The microprocessor 1 which receives the external interrupting signal starts a program to read the changed digital signal S1 and the time signal S2 for the occurrence of the state change which is stored in the storage circuit 7, and thus, the conventional error due to the processing time or the like of the program is not generated when the time of the occurrence of the state change of the digital signal is read. |
