CSCS2650 Computer Organization

PROJECT: DEBUG A PROGRAM (dap0)

OBJECTIVE

Create a simple debugging output routine to help investigate issues in program logic.

TASK

Implement a Vircon32 assembly subroutines that displays the 32-bit hexadecimal value of an indicated item to the display at a provided set of coordinates (supplied via the stack).

Specifically, you want to call the subroutine _debug, and place it in a file called debug.s so that you can %include it as needed in your debugging efforts.

It is written entirely in Vircon32 assembly language, using no compiler-generated routines from the Vircon32 API (no print, no itoa)- you want to create whatever supporting routines are needed.

Pass 3 parameters via the stack:

  • value to display (first added)
  • X coordinate (second added)
  • Y coordinate (third added)

Be sure to preserve all register and important system states (ie whatever was going on before the call to debug must be preserved: save and restore)

Make use of the stack instructions PUSH and POP, although all stack access does not have to exclusively be via PUSH and POP.

Utilize bitwise logic in the process to convert each nibble of data into the value/region you will display

Try it out on some existing code, posting a screenshot (with context) to the class discord.

Provide usage instructions (what needs to be added to existing code to use your debug subroutine)

SUBMISSION

To be successful in this project, the following criteria (or their equivalent) must be met:

  • Project must be submit on time, by the deadline.
    • Late submissions will lose 33% credit per day, with the submission window closing on the 3rd day following the deadline.
  • Processing must be correct based on input given and output requested
  • Output, if applicable, must be correct based on values input
  • Code must be nicely and consistently indented and aligned
  • Code must be consistently written, to strive for readability from having a consistent style throughout
  • Code must be commented
    • Sufficient comments explaining the point of provided logic MUST be present
  • Track/version the source code in your private semester repository
  • Submit a copy of your source code to me using the submit tool by the deadline.

SUBMIT TOOL USAGE

Let's say you have completed work on the project, and are ready to submit, you would do the following (once on LAB46, with all your data present):

lab46:~/src/SEMESTER/comporg/dap0$ make submit

You should get some sort of confirmation indicating successful submission if all went according to plan. If not, check for typos and or locational mismatches.

RUBRIC

I'll be evaluating the project based on the following criteria:

182:dap0:final tally of results (182/182)
*:dap0:submitted file called debug.s or debug.asm [13/13]
*:dap0:subroutine is called _debug or __debug [13/13]
*:dap0:code assembles with no warnings or errors [13/13]
*:dap0:parameters obtained via the stack [26/26]
*:dap0:register states preserved across call [13/13]
*:dap0:debug subroutine uses the stack [26/26]
*:dap0:process utilizes bitwise logic [26/26]
*:dap0:screenshot of subroutine in action to discord [13/13]
*:dap0:code contains usage instructions in comments [13/13]
*:dap0:output contains display of contents at coordinates [13/13]
*:dap0:functionality is correct and to specifications [13/13]

ADDITIONALLY

  • Solutions not abiding by spirit of project will be subject to a 50% overall deduction
  • Solutions not utilizing descriptive why and how comments will be subject to a 25% overall deduction
  • Solutions not utilizing indentation to promote scope and clarity or otherwise maintaining consistency in code style and presentation will be subject to a 25% overall deduction
  • Solutions not organized and easy to read (assume a terminal at least 90 characters wide, 40 characters tall) are subject to a 25% overall deduction