Compiler null for user program for programmable

摘要

PURPOSE:To generate an object program having an excellent size efficiency without lowering the easiness of the programming of a user program in a sequential function chart(SFC) language. CONSTITUTION:A source program in a chart which contains all illustrating information of steps, transitions, coupling lines, and various kinds of terminals written in an SFC language and generated by a user is given to this user program compiler from a working memory 3. Only the information required for the execution of a user program by means of a programmable controller, such as the steps, transitions, etc., and minimum information required for restoring an inputted chart are converted into SFC object codes. Then an SFC object program which is composed of SFC object codes required for the execution of the user program and the necessary minimum information required for the restoration of an inputted chart is transferred to a user program memory 6.