Machine & Assembly Languages. 20 Points

This homework will test your understanding of Machine & Assembly

Languages that we covered in lecture from Chapters 5, 6 & 7 of your

textbook. Submit your homework on Canvas before the due date and time

with your name(s) in the program header at the top of each file. Name your

files, PrintLetters.bin, Guess.asm and Count.asm (if attempting extra

credit).

No late work or email submissions will be accepted.

Instructions

Write down the steps before you start with the Simulator and editor.

You dont need to submit these but will help greatly in completing the

work.

Start your program at x3000 so that it will be easier for me to grade it.

Each program must include a header comment that has your name(s)

and a brief description of the program.

Make sure to comment each line of code in the case of machine code

and have adequate comments in case of assembly code. You will be

graded on comments.

1. (7 Points) Write a machine language program for the LC3. It should

print out the letters: ZYX..DCBAABCD....XYZ That's a total of 26 *2 =

52 letters. You must use one or two loops.

Name your file PrintLetters.bin.

Rubric:

Machine code compiles - 3 Points

Works correctly 2 Points

Commented adequately 2 Points

Named incorrectly (-1 Point)

2. (13 points) Write an assembly language program to simulate a

simple guessing game. The program has stored the value 6. The

program will continually ask the user to guess a number between 0

and 9 (see sample program input/output below.). If your program

encounters any non-digit character, the program should output Invalid

input. Invalid input should still count as a guess. User enters input

and hits enter. The ASCII code x0A causes the cursor to go to the

next line (Newline). Name your file Guess.asm. Assume that the user

gets it right within 9 guesses.

Sample Output

Guess a number: 5

Too small.

Guess again: 9

Too big.

Guess again: a

Invalid input.

Guess again: 6

Correct! You took 4 guesses.

Rubric:

Assembly code compiles - 3 Points

Works correctly for all cases 6 Points

Output matches above sample 2 Points

Commented adequately 2 Points

Named incorrectly (-1 Point)

Extra Credit (10%): Write an LC-3 assembly language program that counts

the number of 1s stored in R5 and stores the result into R4. For example, if

R5 contains 0001 0011 0111 0000, then after the program executes, the

result stored in R4 would be 0000 0000 0000 0110. Name your file

Count.asm.