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Consider the following statements: The 8259A Programmable Interrupt Controller can 1. Manage eight interrupts 2. Vector can interrupt request anywhere in the memory map 3. Have an 8-bit or 16-bit interval between interrupt vector locations 4. Be initialized with operational command words Which of the above statements are correct?

Consider the following statements: The 8259A Programmable Interrupt Controller can 1. Manage eight interrupts 2. Vector can interrupt request anywhere in the memory map 3. Have an 8-bit or 16-bit interval between interrupt vector locations 4. Be initialized with operational command words Which of the above statements are correct? Correct Answer 1, 2, 3 and 4

Features of 8259 A Programmable Interrupt Controller (PIC) include:

  • It is used when several I/O devices transfer data using an interrupt and all connected to the same interrupt level of the microprocessor.
  • It can manage up to eight vectored interrupts for the microprocessor.
  • It can vector an interrupt request anywhere in memory
  • All the 8-vector interrupts can be spaced or priorities at an interval of 4-bit or 8-bit locations but it can be 16-bit also if an additional 8259 A are cascaded.
  • Compatible with 8-bit as well as 16-bit processors.


It also accepts two kinds of command words:

1) Initialization command words (ICWs)

2) operation command words (OCWs)

This is generated by the CPU.

∴ Based on the above points about 8259A, all the given statements are correct.

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