This page refers to the intellivision carts made by Coleco that don't work on an intv2 (Carnival, Donkey Kong, Mouse Trap, and maybe Venture) because Mattel used a potentially illegally lock-out method. Full details are at Blue Sky Rangers.
NOTE: This mod involves shorting a bus data signal to a bus control signal. IMHO, it is much more risky than other mods. YOU DO THIS AT YOUR OWN RISK. I've tried this and had success, the trick seems to be turning on power, waiting 1/2 a second, then pushing the button for 1/2 second. Please send an email of your results if you try it. This mod was posted to usenet by Staceman on Dec 8, 1999.
Don't think this will work for Word Fun. Not sure about any long-term damage to an intv2 (but who plays these games much?). And still have no idea how this guy came across this in the first place, shorting pins at random --yech! --John
It doesn't involve fiddling with the chips at all! All it involves is hooking up a momentary contact switch between pins #38 and #40 of the cartridge port. If you're electronically inclined, you can do a quick test of this by taking the top off of the Intellivision II, and with the front of the unit facing you, count from the back of the unit, to the 3rd and 4th pins of the cartridge port (the row of pins that you can get to easily, not the lower ones). With the system all hooked up, pop in a Coleco cartridge (this has been tested with Donkey Kong, Carnival, Mouse Trap, and Venture), turn the unit on, and take something metal (insulated or ot, it won't shock you) and touch the 2 pins together just once, then pull away. The game should then come on. I'm surprised that no one else has figured this out! I figured it out a few years back by trial and error, but never got around to writing up any documents about it, which I plan to do now real soon. If you know what you're doing, you can probably do the whole mod by just what I'm telling you here. Just get a momentary contact switch, drill a hole and mount it on the unit somewhere (preferrably to the right of the cartridge port; I put mine on the left, making it hard to push when an Intellivoice is plugged in), solder 2 wires to it, and the other ends to pins #38 and #40 of the cartridge port, preferrably on the bottom of the board. There are 2 rows of pins to the port, and the first and last pins of each row are numbered on top of the board; The front row, (the row closest to the cartridge) is numbered odd, and the back row is even. Good Luck! Staceman Oh yeah, gotta throw in the usual disclaimer: I won't be held responsible if you screw up your Intellivision II or any cartridge in the process of trying this mod! --:
BONUS: A followup email!
I was test driving the "new" Yahoo search engine today for my nickname "Staceman" and was surprised to come across a reference to an old Usenet posting I made a few years back regarding the Intellivision II mod for playing Coleco carts! Even more ironic, is how just the other day I was doing some tidying up of some files from an old hard drive I had lying around, and came across a plain text file of that exact post, and wondered "Hmmm.. I wonder if I ever posted that? It would be a shame if I didn't..." Anyway, in answer to your question about the mod on the page- yes, I discovered the mod by shorting pins at random! Crazy, yes, I know... but I did have an extra IntvII, and the carts I was testing with, I had doubles of as well, so it was all good. ;-) And of course, the end result was interesting and possibly of help to some people. I do remember ruining one of my many Demon Attack carts I had at the time in the process. No idea why I was performing the test on that game though. I use to do a lot of poking around with the innards of game systems. I also came up with one of the earlier Jaguar rotary contoller mods. If you've ever looked around the 'net for such a thing, mine's the one that has an "Indy 500" driving paddle coming out the back of a standard Jaguar controller. Didn't work all that well (the sensitivity wasn't very sensitive), but was fun to make nonetheless. ;-) Since then there's been a few other more effective mods released, utilizing the proper optical sensors. So anyway, great site, and keep up the good work! -Stace
NOTE: ONCE AGAIN, YOU DO THIS MOD AT YOUR OWN RISK