Which technique checks the value of each of several instruments one after another?

Which technique checks the value of each of several instruments one after another?

• A. Polling
• B. Duplexing
• C. Scanning
• D. Simplex

Answer: (C)

Reading multiple instruments in sequence is described as scanning. It means the controller cycles through the list of instruments in a fixed order and reads each value one after another, giving you a regular, sequential snapshot of the whole system. This approach is ideal when you want to monitor many devices without targeting a single one for immediate attention. Polling also reads devices one by one, but it centers on the master actively requesting data from each instrument, whereas scanning emphasizes the automatic, repetitive pass through the set. Duplexing and simplex relate to how data is transmitted (two-way versus one-way) rather than how you sequentially sample several instruments.

Reading multiple instruments in sequence is described as scanning. It means the controller cycles through the list of instruments in a fixed order and reads each value one after another, giving you a regular, sequential snapshot of the whole system. This approach is ideal when you want to monitor many devices without targeting a single one for immediate attention. Polling also reads devices one by one, but it centers on the master actively requesting data from each instrument, whereas scanning emphasizes the automatic, repetitive pass through the set. Duplexing and simplex relate to how data is transmitted (two-way versus one-way) rather than how you sequentially sample several instruments.