2600 Pac Man Arcade bug

[tkarner]

Didn't get any responses on the 2600 forum so I thought I'd try here...

 

Apologies if this has been discussed before. I've come across an odd bug while playing Pac-Man Arcade. It seems that sometimes, not everytime, a maze begins with two or three random pellets missing. There is just an empty space where there should be a pellet. First time it happened I thought no big deal, it's just 20 or 30 points less when I finish the maze. But the problem is that because of the missing pellets you can never finish the maze. Apparantly the program counts how many pellets are eaten and when the count reaches N it knows the maze is complete. Well, with the missing pellets the count never reaches N. Pac-Man is left wandering an empty maze with the four ghosts in pursuit, ad infinitum.

 

After some experiments I discovered that this problem only occurs when playing on a short-rainbow 2600 Jr. I tried the cartridge in a standard six switcher, and then a long-rainbow junior and it worked fine. I plug it into my short-rainbow junior and the bug comes back. Curiously, Ms. Pac-Man (on which Pac-Man Arcade is based) plays fines.

 

Those are the only three systems I currently have access to so I don't know if the bug occurs in other versions of the 2600, clones, modded FB2, or the 7800.

 

Any experts out there care to speculate about the cause?

[A.J. Franzman]

Well, if your Junior is the only console that has this problem, it's possible that it's a bad chip in the console.

[djmips]

Is the ROM available? I could try it on my short rainbow jr.

[tkarner]

Well, if your Junior is the only console that has this problem, it's possible that it's a bad chip in the console.

 

That's one possibility but all other games seem to work well on the console... Very strange.

[Vic George 2K3]

The only bug I have playing Pac-Man Arcade on my 2600 is the little picture jumps that happen on occasion.