Which IRQ does the system timer commonly use?
-
0
-
1
-
5
-
10
In the standard x86 PC architecture, IRQ 0 is the highest priority interrupt and is permanently assigned to the system timer (Programmable Interval Timer). This allows the OS to maintain the system clock and perform task switching.
To answer this question, you need to understand the concept of IRQ (Interrupt Request) and its association with the system timer.
IRQ is a signal that is sent to the processor to request its attention. It is used to handle various events and devices in a computer system. Each IRQ is associated with a specific hardware device or event.
The system timer is responsible for keeping track of time and generating periodic interrupts. It is commonly associated with IRQ 0.
Now, let's go through each option to understand why it is correct or incorrect:
Option A) 0 - This option is correct because the system timer commonly uses IRQ 0. This IRQ is reserved for the system timer.
Option B) 1 - This option is incorrect. IRQ 1 is commonly associated with the keyboard controller.
Option C) 5 - This option is incorrect. IRQ 5 is commonly associated with the sound card.
Option D) 10 - This option is incorrect. IRQ 10 is commonly associated with the secondary ATA (Advanced Technology Attachment) controller.
The correct answer is A) 0. This option is correct because the system timer commonly uses IRQ 0.