What do CompactLogix I/O modules have on-board that classifies them as intelligent devices?

CompactLogix I/O modules are classified as intelligent devices primarily due to the presence of processors on-board. The inclusion of processors allows these modules to perform local processing and control tasks, making them able to handle complex functions independently of the main controller. This capability enhances their ability to communicate effectively with the main control system, execute instructions, and manage I/O operations efficiently.

In contrast, while memory is essential for storing data and instructions, it does not confer the same level of processing capability that a processor does. Connections are important for communication between devices, but they do not contribute to the intelligence of the I/O module itself. Power supplies are necessary for operation but do not play a role in the classification as an intelligent device. Thus, the ability to process information and manage tasks autonomously is what sets CompactLogix I/O modules apart as intelligent devices.