| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor control system having a function of self-diagnosing a bus connection of the system without providing a test special purpose check land and an I/O and a function of specifying a fault position of a component, a signal line or the like from a self-diagnosing result. SOLUTION: A self-diagnostic method for the motor control system comprises a first step of outputting an L potential by setting I/O ports 31-3X to an output port, then a second step of switching the ports 31-3X to an input port, a third step of waiting a delay time of time constants of pull-up resistors 41-4X, and a fourth step of checking inputs of the ports 31-3X. In the fourth step, if the resistors 41-4X are normally connected, the inputs of the ports 31-3X are changed to an H potential by the pull-up resistors. Accordingly, it is determined to be normal. If there is a disconnection or a short circuit with the L potential, the L potential remains as it is, and the fault can be detected. |
