$2$:$054$

$4.$ Given a hypothetical Machine with CPU and Memory and opcodes below: $(15$ points$)$

$\backslash$table$[[$Memory$],[300,1941],[301,5940],[302,2941],[303,9942],[304,8940],[dots,],[940,0007],[941,0002],[942,0005]]$

$\backslash$table$[[\backslash$table$[[$CPU$],[$Regist$],[$ers$]]],[300,$PC$],[,$AC$],[,$IR$]]$

Where each opcode is defined below:

$0001=$ Load AC from memory

$0010=$ Store AC to memory

$0101=$ Add AC from memory

$2$:$05$

Where each opcode is defined below:

$0001=$ Load AC from memory

$0010=$ Store AC to memory

$0101=$ Add AC from memory

$1000=$ Load I$/$O to memory

$1001=$ Store $AC$ to $\frac{\text{I}}{O},($I$/$O number is stored in a memory location$)$

I$/$O number $5$ refers to a monitor

I$/$O number $6$ refers to a printer

I$/$O number $7$ is the sensor connected to the machine

Trace the execution starting from Program Counter$=300($PC $=300)$ and answer the following questions:

$($a$).$ when $PC=300,$ what does CPU do and what is the content in AC$,$ IR and memory location $940-942?$

$($b$).$ when PC$=301,$ what does CPU do and what is the content in $AC,IR$ and memory location $940-942?$

$($c$).$ when $PC=302,$ what does CPU do and what is the content in AC$,$ IR and memory location $940-942?$

$($d$).$ when PC$=303,$ what does CPU do and what is the content in AC and IR$?$

$($e$).$ when $PC=304,$ what does CPU do and what is the content in memory $940$ and $941?$