Q4Microprocessor and Interfaces
Question
4 marks
Discuss the 8259 Programmable Interrupt Controller (PIC).
Answer
The 8259 Programmable Interrupt Controller (PIC) is an IC used to manage hardware interrupts.
The 8259 Programmable Interrupt Controller (PIC) is an IC used to manage hardware interrupts in microprocessor systems. It resolves priority among 8 interrupt sources.
When multiple interrupts arrive, the 8259 evaluates their priorities, sends an INTR signal to the CPU, and then provides the 8-bit vector address of the highest priority interrupt on the data bus during the INTA cycle. It can be cascaded to handle up to 64 interrupts.