Local variables are storage locations for data. Local variables function like virtual points except that they require less memory, are predefined, and cannot be directly displayed.
- Local variables can contain analog or digital values.
- Each set of local variables is designed for a specific task.
- Local variables are divided into two categories: subroutine and global storage variables.
- Local variables are only local to the device through the web interface. They are not available over BACnet.
- Local variables cannot be read by other devices on the BACnet network and cannot be used in their applications.
- Local points using the Local statements can be seen in the PXC.A controller web interface.
- To make a point network-visible, it must be created outside of the PPCL program (BACnet AV, BV, or MSV). Local variables in PPCL can be bound to these BACnet virtual points and in turn can be ready by other devices over the network.
PPCL supports the following local variables:
- $ARG1 through $ARG15, which are used for subroutines.
- $LOC1 through $LOC15, which are used to store the results of calculations.
- LOCAL (the definition of user-defined local variables in APOGEE automation stations is discussed in Chapter 3 – Syntax.
For APOGEE automation stations, each program has unique $ARG and $LOC variables. $LOC points can also be viewed and commanded through the interface using the program name, system delimiter (:), local variable name format.