16.1 INTRODUCTION
This chapter covers advanced functions, but this definition is somewhat arbitrary. The array functions in the last chapter could be classified as advanced functions. The functions in this section tend to do things that are not oriented to simple data values. The list functions will allow storage and recovery of bits and words. These functions are useful when implementing buffered and queued systems. The program control functions will do things that don't follow the simple model of ladder logic execution - these functions recognize the program is executed left-to-right top-to-bottom. Finally, the input output functions will be discussed, and how they allow us to work around the normal input and output scans.
