When the enabler determines it is time to query a device for point values, it groups the points within like domains into caches. By definition, a cache starts at a given memory location and spans a given number of bytes.
Polling of points may be interrupted by certain events such as a request to set a point value. The min_points_to_poll variable defines how many caches must be processed before the query of point values may be interrupted.
3. Define the protocol.