What does it indicate when a local I/O bit is displayed in a darker gray?

When a local I/O bit is displayed in a darker gray, it indicates that the I/O point has been assigned. In Rockwell ControlLogix systems, the color coding of I/O bits is used to provide a quick visual reference regarding their status. A darker gray typically signifies that the specific I/O point is actively assigned within the program or configuration, meaning it is being used for its intended purpose in the control system. This visual cue helps programmers and operators quickly identify which I/O points are in use, improving the efficiency of monitoring and troubleshooting tasks.

Understanding the status of I/O points is crucial for effective control and automation operations, as assigned points correspond to physical inputs or outputs that the control logic interacts with.