Question

Write a machine language program to input two one-digit numbers, add them, and output the one-digit sum. There can be no space between the two one-digit numbers on input. Write the program in a format suitable for the loader and execute it on the Pep/9 simulator. It needs to be in hexadecimal, I am just confused on how to input numbers on the PEP/9 machine.

Answer 1

Greetings!!

Code:

BR MAIN ;Branch to main program

PROMPT: .ASCII "PLEASE ENTER THE NUMBERS\X00" ;prompt message

N1: .BLOCK 1 ;variable for number 1

N2: .BLOCK 1 ;variable for number 2

SUM: .BLOCK 1 ;variable for storing sum

MAIN: STRO PROMPT,D ;prompt the message on to the screen

DECI N1,d ;read first number from the user

LDA N1,D ;load first number to accumulator

DECI N2,D ;read second number from the user

ADDA N2,D ;addd accumulator content with second number ie add both the numbers

STA SUM,D ;store the answer to the variable SUM

DECO SUM,D ;display sum

STOP ;stop

.END

Output screenshot:

Hope this helps