Batch Forensics: The Case for Link Groups – Class based Unit Synchronization
To coordinate activities between units, take advantage of product functionality to greatly reduce controller code. Programing and unit coordination are used during activities such as material transfer from one unit to another and may be used to coordinate recipe pause points in a unit while the recipe of another unit reaches the desired step, or may be used to transfer process data from one unit to another for further evaluation, etc.
Using product functionality to create a class-based solution while minimizing programming greatly simplifies the complexity of the code. The product functionality consists of link groups and Phase logic phase requests (PXRQ for phase manager phases and RQ for classic OPC phases).
To better understand its usability, we will use a sample process consisting of units capable of transfer material with each other, One to Many, Many to One, Many to Many. In any of these examples, keeping track of who the groups involved in a synchronization can be as simple as specifying the required pairs (more than two concurrent can be done as well) in the procedural (recipe) model.
Let’s look at several scenarios: