APPENDIX A - Valtek

NT11S Internal ProcessingAppendix FAPPENDIX FNT11S Internal ProcessingWhen host link/NT link is used, the following processing is executed inside the NT11S. Processing is divided intotwo types: periodic processing and event processing.Periodic ProcessingWhen the NT11S is in the RUN mode it executes the following internal processing cyclically. The contents of all theallocated bits and words used for screen display are read from the PC at one time, allowing high-speed processing.[NT11S processing]NT11S power ON[Details of processing]Initial processingHardware check, communication status check, etc.,executedOperation startInitial values written to the memory tablesScreen switching(PT!PC)When the values registered in the NT11S are used asthe initial values in the memory tables, these values arewritten into the allocated words of the PC.The allocated bits and words for the displayelements that have to be read from the PC areregistered in the PC.(PT!PC)Registration of the read allocated bits and words in thePCReading of allocated bits and words(PT#PC)The contents of the allocated bits and words registeredin the PC are all read at one time.Note- Only the data of the PC Status Control Area and data for currently displayedscreens is read from the PC.Even if the contents of the PC words allocated as memory tables are changed,the data are not upgraded at the NT11S unless these memory tables are usedfor screen displays.- The maximum number of bits/words that can be read is 120 words per screen.If the number that can be read is exceeded, the data are not upgraded.156