CS609 System Programming Assignment 1 Solution 2017

Problem Statement:

Write a TSR (Terminate and Stay Resident) program that will show your VUID whenever “R” key is pressed and clear the screen whenever “C” key is pressed.


1)      In this program, you have to intercept keyboard interrupt (0x09) and write your own interrupt function.

2)      Your VUID must be displayed (whenever R key is pressed) starting from the beginning of monitor text memory area 0xb8000000

3)      The screen must be cleared whenever “C” key is pressed. To achieve this, fill space character in whole text

memory area with white foreground color and black background color.

4)      VUID should be displayed in normal font (bold font is not required), having black foreground color and white background color; and text should blink on the screen.

5)      Complete ASCII table and Scan Code table are available in Downloads section of LMS.

6)      You should install Virtual Box and run Windows 98 in it to compile/run the code. Step by step instructions of how to install Virtual Box/Windows 98 and making COM file (TSR) are available in Downloads section of LMS.

7)      After successfully running your code, you should take snapshot of the output and paste it in your assignment solution file.

8)      There is no need to submit COM file. Your solution must be in a single word file (.doc or .docx) containing:

  1. Complete code (written in Word file)
  2. Output screenshot

9)      You can use Consolas font for enhancing readability of the code in Word file.



You should NOT use interrupt 21/09H to display your VUID. It must be displayed only by accessing monitor text memory area.