USE LC$3$

This is a programming assignment that will be graded and scored as a home work since it is so simple.

This one is less simple than previous assignments

Write a subroutine for the LC$3$ that will stop and wait for the user to enter a single digit number from $0$

to $9.$ The subroutine should function in a way like GETC but should not return until a digit is pressed. If

anything other than a numeric character is pressed the program should simply ignore the character.

The "MAIN" part of your program $($the top lines$)$ should look like this.

$\backslash .$orig x$3000$

MAIN

JSR GETNUM

JSR GETNUM ;Yes, there are TWO calls to GETNUM

HALT

GETNUM waits for a digit to be pressed then returns the value of that digit in R$0.$ So$,$ if a $5$ is pressed,

the number $5$ should be stored in R$0$ after GETNUM returns. NOTE that this is the number $5$ and not the

ASCII code for $5.$ You will have to convert since GETC returns ASCII codes.

Since you are running GETNUM twice from main, it means you will have to type TWO digits for the

program to finish. Only the second digit will be stored in R$0$ after the program ends since the second call

to GETNUM will overwrite the value of the first call.

ALL OTHER INPUTS SHOULD BE TREATED AS IF THEY DIDN'T HAPPEN.

Some examples:

If you run the program and type wxyz$56,$ the first call to GETNUM should ignore w$,$ x$,$ y$,$ and z and return

with $5$ in R$0.$ Then GETNUM will be called again and will return $6$ in R$0.$ So after your program runs, if

you type wxyz$56,$ the number $6$ should be in R$0$ and NOT decimal $54$ or the hex value $36.$

If you run the program again and type abce!!:$*7$ww$\}\}\{\{8,$ the first call to GETNUM will ignore everything

up to the $7$ and return with $7$ in R$0.$ Then GETNUM will be called again and will ignore the ww$\}\}\{\{$ and

return with the number $8$ in R$0.$