Prob $4.$ Consider the problem of interrupt priority setup with the following

assumptions:

We only use the most significant $6$ bits of the byte in each IP register. $($Again the priority number is

expressed in a $6-$bit unsigned number.$)$

We set up the system to use $3$ bits for preemption priority.

We set up the priority of IRQn$3$ using NVIC$\_$SetPriority $($IRQn$3,18)$;$.$

Now, we consider the setup for the priorities of three other interrupt sources, represented by IRQn$0,$IRQ$1,$

IRQn$2,$ respectively. Answer the following questions:

What are the values of PPN and SPN of IRQN$3$ in decimal? What is the value read from IP$[$IRQn$3]$

directly in hexadecimal?

If we want IRQn$0$ to be able to preempt IRQn$3,$ what will be the range of priority number we can use

when setting it up$?$

If we want IRQn$3$ to be able to preempt IRQ$1,$ what will be the range of priority number we can use

when setting it up$?$

If we do not want IRQn$2$ to preempt IRQn$3,$ what will be the range of priority number we can use when

setting it up$?$