Rick Koenig's Intellivision Debugger

[decle]

Hey Guys,

 

Through October I took a look at the Intellivision debugger written by Rick Koenig back in 1982 / 1983 when he worked for Mattel as a Blue Sky Ranger.  A twist of fate led to a version of this software being left in the production ROM of World Championship Baseball, where it can be found to this day.  I blogged about this investigation as a RetroChallenge entry.  If you've been following along, you will have seen that I had some success in getting Rick's work up and running.

 

You can find a summary of my findings in the following document which, thanks to the kind permission of the Intellivision Productions, also contains the full source of Rick's debugger with my annotations by way of explanation.

 

rickKoenigIntellvisionDebugger-20191107.pdf

 

If you fancy playing with the debugger you can find a version of David Rolfe's demo game Killer Bees with the Rick's work embedded within it here:

 

killerbees.zip

 

Instructions for how to use the debugger can be found in my blog, in the document above and in the following video which shows it in use:

 

 

As always any feedback is most welcome (other than the fact that I got the addressing mode of the MOV instruction at 3:40 wrong - it should be direct, not immediate mode). ?

 

Cheers

 

decle

 

Edited November 7, 2019 by decle

[+Lathe26]

Thank you very much for this investigation.  I'd kicked around the idea of investigating it myself, as well as writing my own version to share with the community, but it was always low on my priority list.

 

Side note: I still think it would be cool if someone shared a debugger like this one with the community to help with game debugging on real hardware. 

[JohnPCAE]

This makes me wonder if the developers had a special controller box that interfaced into the controller ports for making it easier to use the debugger, i.e. something with a layout specifically designed for debugging use.

[intvnut]

On 11/18/2019 at 11:17 AM, JohnPCAE said:

This makes me wonder if the developers had a special controller box that interfaced into the controller ports for making it easier to use the debugger, i.e. something with a layout specifically designed for debugging use.

 

Actually... I have seen Rick Koenig's original docs for his debugger (Version 3.0).  He specifically mentions using "two of your business cards" as overlays (presumably drawing the debugger inputs on the back).  I kid you not.

 

Edited December 4, 2019 by intvnut
Include relevant quote.

[decle]

Hey all,

 

This work was done as an entry to the Fall 2019 RetroChallenge, however, as some of you might be aware this instalment of the competition was aborted.   When RetroChallenge rose phoenix-like in April 2020 I asked Mark Sherman if my work might be considered as a retrospective entry and he was kind enough to agree.

 

Well, I'm very pleased to announce that Raiders of the Lost Debugger won...!

 

http://www.retrochallenge.org/2020/08/202004-05-results.html

 

...in the "Weirdest" project category, which as anyone who knows me will be aware, is the highest honour anyone can pay my work.

 

I am stoked that it is named next to projects by hard core people like @paulrobson.

 

Cheers

 

decle

 

Edited September 3, 2020 by decle
links should be links

[+Lathe26]

Awesome to see you recognized for this.  I remember waiting excitedly to read the next installment.  I also remember when you had to switch the Vitruvian Woman to the Vitruvian Mouse.  Congrats!