Question

Differentiate between Hardware and Software interrupts of 8085 Microprocessor. (Any three points)

Answer 1

S. No.	Hardware interrupts	Software interrupts
1.	Asynchronous events are handled using hardware interrupts.	Asynchrenous events are handled without the need of software interruptions.
2.	An external device requests these interruptions.	These interruptions are requested by the CPU itself, not by an external device.
3.	The program counter is not increased following the execution of these interrupts.	The program counter is increased when these interrupts are completed.
4.	To acknowledge this interrupt, the microprocessor either runs an ideal machine cycle or an interrupt acknowledge cycle.	The microprocessor does not carry out any acknowledgement cycles for interrupts. It follows a typical instruction cycle.
5.	These interruptions could be maskable or non-maskable.	They cannot be ignored or hidden.
6.	Compared to any program interruption, they are less important.	Interrupts from software are given priority over those from hardware.
7.	These interruptions have an impact on the logic that controls them.	These interruptions have no effect on the logic that controls interrupts.
8.	It increases the system's throughput.	The system's throughput is not improved by them.