Question

Which is used to prioritise multiple requests?

(a) dual address mode

(b) single address mode

(c) arbitration

(d) chaining

This question was addressed to me in an interview for internship.

My doubt stems from DMA-II in section Basic Peripherals of Embedded Systems

Answer 1

Correct option is (c) arbitration

To explain: The arbitration is used to provide priority for multiple access. This uses a priority scheme which may offer fair priority to the one channel, or a high priority to the other channel and so on. Such condition is otherwise known as round-robin condition in which the priority is equally divided.