Question

Consider the following statements about interrupts.
Statement-I: Internal interrupts are synchronous with the program while external interrupts are asynchronous.
Statement-II: Internal interrupts are called traps. The correct answer is

• A. Statement-I is true, but Statement-II is false
• B. Both Statement-I and Statement-II are true
• C. Statement-I is false, but Statement-II is true
• D. Both Statement-I and Statement-II are false

Hint:

Internal Interrupts = Traps = Synchronous External Interrupts = Hardware Interrupts = Asynchronous

Answer 1

The Correct Option is B

Concept: An interrupt is a mechanism that temporarily stops the normal execution of a program so that the processor can service an event requiring immediate attention. Interrupts are generally classified into:
• Internal Interrupts
• External Interrupts Internal interrupts are generated by the CPU itself during program execution and are therefore synchronized with the currently executing instruction stream. External interrupts originate from hardware devices such as keyboards, timers, printers, disks, and I/O controllers. These events occur independently of program execution and hence are asynchronous. Internal interrupts are commonly known as traps.

Step 1: Examine Statement-I.
Statement-I says: \[ \text{Internal interrupts are synchronous} \] and \[ \text{External interrupts are asynchronous}. \] Internal interrupts occur due to events such as:
• Division by zero
• Arithmetic overflow
• Invalid opcode
• Protection violation These occur during instruction execution and are therefore synchronous. External interrupts originate from external devices and occur independently of the currently executing instruction. Thus Statement-I is true.

Step 2: Examine Statement-II.
Statement-II states: \[ \text{Internal interrupts are called traps}. \] In computer organization, exceptions generated internally by the CPU are often referred to as traps. Examples include divide-by-zero traps and overflow traps. Therefore Statement-II is also true.

Step 3: Determine the correct option.
Since both statements are correct, \[ \boxed{\text{Both Statement-I and Statement-II are true}} \] Hence option (B) is correct.