| 摘要 |
PROBLEM TO BE SOLVED: To provide a programmable logic controller which permits program modification, instruction addition, and customization through simple operation without requiring any special hardware such as a PROM writer and a device adapter. SOLUTION: At least, part of a system program memory is composed of a nonvolatile memory which is rewritable in a mounted state and the rewritable nonvolatile memory is provided with a system program storage area which corresponds to an additional function; and this controller is provided with a mode setting means which sets an operation mode to a system program part modification mode, a connector where an external storage medium stored with a system program corresponding to the additional function is fitted detachably, and a program transfer means which transfers the system program corresponding to the additional function stored in the external storage medium connected through the connector to the system program storage area corresponding to the additional function of the system program memory on condition that the operation mode is set to the system program part modification mode.
|
