IBDP Computer Science A1.3 Operating systems and control systems HL Paper 1 - New Syllabus
▶️ Answer/Explanation
One purpose of paging is to enable a process to use virtual memory.
The operating system divides memory into fixed-sized pages. If a process needs a page that is not currently in RAM, the OS can retrieve that page from secondary storage and load it into primary memory. This allows programs to run even when all of their pages cannot be held in RAM at the same time.
Paging also helps the operating system manage memory efficiently because pages can be moved between primary and secondary memory as required, rather than requiring one large continuous block of free RAM.
Answer: Paging allows a process to use virtual memory; when a required page is not in RAM, the OS loads it from secondary storage into primary memory.
▶️ Answer/Explanation
The microprocessor acts as the controller of the home alarm system.
• It continually receives input from sensors, such as door, window or motion sensors, as well as settings entered by the user.
• It processes these inputs by executing stored instructions and may compare sensor readings with predefined values or conditions to determine whether an abnormal event has occurred.
• If the required condition is detected, the microprocessor sends signals to output devices or actuators. For example, it may activate an audible alarm or trigger a notification, text message or call to the homeowner or monitoring centre.
Therefore, the microprocessor performs the central input → process → output role of the alarm system, deciding how the system should respond to information received from its sensors.
Answer: The microprocessor receives data from sensors, processes and compares this data according to stored instructions, and sends appropriate signals to output devices such as an alarm or notification system.