D
Don Hodges
donhodges.com · Personal blog · on HN since 2008
Don Hodges analyzes classic arcade games like Pac-Man, Donkey Kong, and Galaga at the code level, finding and fixing bugs.
What HN saysHN commenters recommend it for explicit low-level details on arcade games, including kill screen patches and ghost AI bugs, with the non-arcade pages to be ignored.
18HN people shared it
9linked it in comments
13stories submitted
181story points
4 years agolast shared
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Most-shared posts
- 1The Journey to Find, Analyze, and Fix Pac Man’s Split Screen (2007)10 people · 50 points · first shared 2008 · 1 comments on HN
- 2Controlling the Barrels in Donkey Kong2 people · 66 points · first shared 2015 · 8 comments on HN
- 3A modulo arithmetic error in PacMan's ghost AI?2 people · 50 points · first shared 2010 · 5 comments on HN
- 4How high can you get: Fixing the Donkey Kong kill screen1 people · 5 points · first shared 2009 · discussion on HN
- 5Galaga's level wraparound bug, analysed and fixed.1 people · 3 points · first shared 2010 · discussion on HN
- 6A Prayer to the Global Corporate Gods1 people · 3 points · first shared 2021 · 1 comments on HN
- 7Donkey Kong Lays an Easter Egg (2009)1 people · 2 points · first shared 2014 · discussion on HN
- 8Retrogame hackers patch bug in 1980 arcade classic 'Phoenix'1 people · 1 points · first shared 2010 · discussion on HN
- 9The High Price of Cell Phones (2007)1 people · 1 points · first shared 2021 · 1 comments on HN
- 10Archive1 people · first shared 2010
What HN people wrote when they linked it
gp2000 · 2016-11-06
The links to Don Hodges site are great if you want the explicit low-level details. For instance, he has a patch to fix the kill screen:
http://donhodges.com/how_high_can_you_get2.htm
I made a much less serious patch -- a backwards-facing Pac-Man that places dots instead of eating them:
http://members.shaw.ca/gp2000/bacman.html
joezydeco · 2010-05-27
This is an interesting set of articles, given the renewed interest in 8-bit arcade games recently (cough cough PAC MAN). Ignore the non-arcade stuff:
http://www.donhodges.com/archive.htm
This all looks like child's play now, but 30 years ago this was cutting edge engineering. These arcade board sets generated pretty great games for the era without framebuffers (RAM was hellishly expensive), high-speed CPUs, or a lot of other conveniences we take for granted today.
bhickey · 2023-02-04
Here's more than you ever wanted to know on the subject:
http://donhodges.com/Controlling_the_barrels_in_Donkey_Kong.htm
http://www.jeffsromhack.com/products/donkeykong_tech.htm
cranklin · 2017-04-03
Pinky's AI has a bug:
http://donhodges.com/pacman_pinky_explanation.htm
Someone · 2017-03-14
If only things were that simple. A demo video can show that there is an interaction that doesn't stutter, not that there is no interaction that stutters.
For an historical analogue: you can show hours of paying PacMan without finding its kill screen (http://www.donhodges.com/how_high_can_you_get2.htm)
STRML · 2016-11-06
The linked Don Hodges article about Level 256 is particularly fun to read, complete with a few proposed patches & a way to make the startup checksum still pass:
http://donhodges.com/how_high_can_you_get2.htm
A fun quote - it certainly seems better to have an ending, even if it is not intended:
> "It is probably a good thing that Pac Man has this bug in its program. If it didn’t, expert players could conceivably be able to play the game indefinitely, because whenever they get tired they can just park Pac Man in the hiding places and leave the game to go eat, sleep, or whatever, and then return to the game and continue playing. The only limiting factor would have been the length of time that the game could run without a power outage or suffering from some other hardware failure. Experts would have been able to play the game for weeks, months, even years, or more."
teh_klev · 2015-07-04
There's been a few interesting articles posted on HN about Pacman's internals and gameplay:
http://www.donhodges.com/how_high_can_you_get2.htm
http://gameinternals.com/post/2072558330/understanding-pac-man-ghost-b…
http://home.comcast.net/~jpittman2/pacman/pacmandossier.html#Chapter_5
You can find the relevant HN discussion by searching HN algolia:
https://hn.algolia.com/?query=pacman&sort=byPopularity&prefix&…
sp332 · 2013-05-01
This page shows how to fix the Pac-Man kill screen: http://www.donhodges.com/how_high_can_you_get2.htm
hhm · 2008-08-28
Ms. Pac-Man: http://cubeman.org/arcade-source/mspac.asm and another one: http://www.donhodges.com/how_high_can_you_get2.htm