Bacteria's project: "Project Unity"

[bacteria]

Third system: Mattel Intellivision


Got the PAL composite mod working fine on the Intellivision console. Got a lot of work to do on the system; rewiring, working out which boards and components can be removed, etc. I'll do as with the NES - complete the work, then open up a fresh console and do the video log - will take several days if not weeks before this work is completed, especially as I also want to test from my stock of Intellivision consoles (I have about 5) which works, which doesn't, etc.


Here is a pic of an opened Intv gamepad.

The Intv gamepad had an interesting feature, the d-pad was a circle and claimed to provide 16 positions of movement instead of the usual 8 (4 plus diagonals).

Before:



After disassembly:



There are two pieces of printed acetate that do the button and d-pad contacts.

Working out what connects to what, will post when known. All traces go back to 9 pins that go into the controller. Want to see if there are combinations that tell the system what is needed, especially on the dpad, and can be connected directly.

[CRTGAMER]

A serious Modder! Seeing that PCB thickness reducing trick on the previous page to easily follow the traces and space saving. Whoa! Looking forward to more ideas with great interest!

[bacteria]

Why do these damn consoles need so many power voltages? I thought it bad enough that the ColecoVision needs -5v as well as +5v and +12v; the Intellivision is a bigger pain in the butt - needs - get this: +12v, +16v, +5v and -3v ; yes not only 16v which is a pain, but also another negative voltage, -3v.

My PSU from an old PC outputs +12v, +3.3v, +5v, -12v and -5v

I can easily have one power supply from mains going into two directions to feed the computer PSU and the Intellivision transformer and extra circuit board; however, would be nice to eliminate that nonsense - so, anyone know how to get -3v from either -5v or -12v (or positive voltages) and also step-up from +12v to +16v? If not, ok, but would be nicer to have things "cleaner" and remove the extra boards.

Ideas?

So far, this Alpha Omega system is going to have to use the following voltages: (this is nuts): +3.3v, +5v, 8v, +12v, +16v, -3v, -5v

I don't suppose there is a single PSU supply that can output that lot either as computer boards only seem to need 12v as max. Like I said, can use two or even three power supply bricks in the final system, will all be hidden anyway, however if there is a cleaner solution... ?

[bacteria]

Worked out the matrix for the keypad and some of the d-pad. I need to work out the 4 main d-pad directions and also see if the diagonals work.

This is precisely why I can't make a controller from the start of the project; what I have learnt from the Intellivision is that it needs three button presses to register the keypad (ie 0-9, clear and enter) but two for some other things (shoulder buttons and some d-pad directions).

Tact switches only allow for two contacts of course, which means i'm going to have to experiment with diodes. That will be interesting! I'll probably have exactly the same problem with the ColecoVision too; I expect that uses a matrix too - after all, like the Intellivision (9 wires, 14 buttons, 16 d-pad directions), the ColecoVision has a lot of contacts too and no doubt more button contacts than wires (hence matrix).

Solution is solvable. This is also why some projects will take longer than others; however, in this case, will mean elimination of the original controller altogether.

[CRTGAMER]

So far, this Alpha Omega system is going to have to use the following voltages: (this is nuts): +3.3v, +5v, 8v, +12v, +16v, -3v, -5v

I don't suppose there is a single PSU supply that can output that lot either as computer boards only seem to need 12v as max. Like I said, can use two or even three power supply bricks in the final system, will all be hidden anyway, however if there is a cleaner solution... ?

PC power supply can handle some, remainder of oddities in original power bricks to feed off one AC power switch?

[bacteria]

Indeed; however, got some converter cards being sent to me, which might handle the -3v and step up for the 16v and 12v; might be able to run whole system off one DC power supply; maybe - will need to experiment when receive them.

[bacteria]

Ok, got all the keypad ok and the four main directions. Diagonals - not quite there, if you connect the equivalent of up and right for example, then you don't get a nice diagonal but less of an angle. The Intellivision d-pad has 16 directions, so for example, if up is 16, right is 4, down is 8, left is 12 then at the moment the diagonals aren't 4, 6, 10, 14 which would be ideal, rather something like 1, 7, 9, 15 as I recall. The d-pad seems to change between the ground + 3rd contact and just ground or just 3rd contact. Not easy to explain.

I'm going to have to build the numpad and use my diodes to get all the contacts working and separate, also make the three contacts required for the circuit into two for the tact switches to work - I have several diodes, so will get on with the build.

BTW - i'm going to have to make my own controller, of course, however have decided on a similar style and feel to a Gamester Xbox controller I have; will need to change the shape of course a bit, and make a little bigger, but keeping to the general style and design. I can coat the controller with clay when i'm ready to, to flatten parts and make others a bit bigger, then vacuum form a nice controller from that. That's the idea anyway; although I can't build the controller until I have all the controls worked out for awkward controls like for the Intellivison - that's one of the reasons I started this console at this stage - proving ground for skills.

I can see this complete project is going to need probably 100+ diodes by the time I finish, no joke.

Here's the working out so far for contacts, based on the Intellivision controller matrix:



For the controller keypad, using these 10mm tact switches - they are ideal, the 3 x 4 grid is exactly the same size as the Intellivision keypad, which means I can use the official overlays on the controller for the game.

[bacteria]

Not getting many reads on this topic, no problem, i'm sure it will increase as the project continues!!


Been very busy today - tried a few combinations, which thinking about it wouldn't work, and sure enough, didn't.

Set on this as the solution, and it works:

Each keypad press needs three connections to work as it works via a matrix, one is ground and two others too. Obviously, a tact switch is only two contacts, so there lies the issue.

The solution is via diodes. I haven't any rectifier diodes (buying a stack, will probably need a couple of hundred for this project), so used zener diodes as had many, all voltages between 5.1 - 9.1 volts - anyway, used them. Reason for using diodes is that I can't have wires sharing their contacts with other buttons, as each wire goes to different places.

There are 9 wires coming out of the controller to feed everything, one is ground (pin 1), each of the other wires is required by 4 button/direction controls, so I soldered 4 diodes to each of the 8 wires; wired the whole thing to the keyboard (bank of tact switches), and the result works properly, all the 0-9 buttons, and clear and enter too. Just have the d-pad section to deal with now; the 4 normal directions are fine, will experiment with getting true diagonals.

No point making a video of it at this stage, here is a pic though; just used hot glue and cardboard to secure the diodes in place - was easy to troubleshoot. I need to buy some more perf board and do it properly.. lol

[bacteria]

Worked out the matrix, works fine. A lot of games don't use the 16 D-pad directions on the Intellivision anyway, and those that do are perfectly playable with four directions. I played Tron Deadly Discs for some time yesterday absolutely fine - in fact, seemed to have if anything more control on the character - the Intellivision controller was a bit "hit and miss" on accuracy at the best of times anyway. Further evidence, if needed, that 4 direction for the D-pad is fine is the "Intellivision Lives" compilations on the PS1 and PS2 as well as the rather poorly ported plug'n'plays for the Intellivision.

Here's the product of several hours work and testing - all works fine. Using tact switches is so much better than the membrane ones, and, the tact switch matrix I built (10mm tacts) is the same size as the original mebrane set, so it would be quite simple to make a new controller with a better keypad and d-pad than the original Intellivision one, and still use the original game overlays! (I'm not making a replicate controller for my project, however this diagram would be useful if you wanted to make one).

(Corrected original pic):

[AppleQueso]

Not getting many reads on this topic, no problem, i'm sure it will increase as the project continues!!

Oh no, personally I find it all absolutely fascinating, I just don't have much to say. I'm sure a lot of folks reading this thread feel the same way.