$3.$ Assuming a $16$M memory for a $16-$bits system, using $512$K Byte RAM chips.

a$)$ How many RAM chips are necessary?

b$)$ If we were accessing one word, how many chips would be involved?

c$)$ How many address bits are needed for each RAM chip?

d$)$ How many address bits are needed for the entire memory?

e$)$ If high$-$order interleaving is used, where is the address $0$x$0000$B$2$ located?

f$)$ Repeat e$)$ for low$-$order interleaving

$4.$ Suppose we have a $16-$bit CPU, with $8$ regular registers, and their current values are:

R$0=0$x$0002$ R$1=0$x $0000$ R$2=0$x $1101$ R$3=0$x $0009$

R$4=0$x $0001$ R$5=0$x $0002$ R$6=0$x $0000$ R$7=0$x $0009$

Also, the following cells represent some parts of the memory, where each cell contains one byte, and the addresses are labeled on the right side. Eg$.$ the value in address $1000$ is: $01011010.$ Here the address is in hexadecimal format.

$...$

$01011010$

$...$

$10000010$

$01000101$

$10001001$

$00000010$

$...$

$...$

$$addr: $1000$

$...$

$$addr: $1008$

$$addr: $1009$

$$addr: $100$A

$$addr: $100$B

Based on von$-$Neuman model, answer the following questions.

$1)$ Currently PC $($program counter$)$ register value is $0$x$1008,$ what is the meaning of this number?

$2)$ what is the data that CPU is going to fetch?

$3)$ What is the PC value after the current cycle?

$4)$ What is the data CPU is going to fetch in the next cycle?

Mnemonic Encoding Description

$.........$

add rS$,$ rD $10000001$ ssssdddd Add register rS to register rD$.$

sub rS$,$ rD $10000010$ ssssdddd Subtract register rS from register rD$.$

mul rS$,$ rD $10000011$ ssssdddd Multiply register rD by register rS$.$

div rS$,$ rD $10000100$ ssssdddd Divide register rD by register rS$.$

and rS$,$ rD $10000101$ ssssdddd And register rS with register rD$.$

or rS$,$ rD $10000110$ ssssdddd Or register rS with register rD$.$

xor rS$,$ rD $10000111$ ssssdddd Xor register rS with register rD$.$

shr rS$,$ rD $10001000$ ssssdddd Shift right register rD by register rS$.$

shl rS$,$ rD $10001001$ ssssdddd Shift left register rD by register rS$.$

$......$

$5)[$Optional$]$ What is the CPU operation according to the fetched data in the next CPU cycle $($check the mnemonic table to get the decoded result$)?$

$6)[$Optional$]$ What is the execution result of the operation in question $5)?($list the value of related register$)$