DIY keypad issues

[Nateo]

A while ago I built my own Coleco stick out of some arcade parts and a wooden project box from Michael's. It works great, but it lacks a keypad, but it given that its rarely needed (and the player 2 keypad works the same way for most titles) I didn't worry about it too much,

But now that I'm home a lot more often and with considerably less plans, I decided to try to hand wire one with some switching diodes and some tact switches. 

The keypad doesn't work. I followed the attached schematic I found through Google. I decided to open up one of my original ColecoVision controllers to see if there was something I may have neglected, and it appears to my eye that the schematic I used is wrong. The diodes on the actual circuit board appear to be facing the opposite direction. Is this in fact my problem? I just want to make sure I'm not replacing 22 or so diodes for nothing. 

[Bmack36]

8 minutes ago, Nateo said:

A while ago I built my own Coleco stick out of some arcade parts and a wooden project box from Michael's. It works great, but it lacks a keypad, but it given that its rarely needed (and the player 2 keypad works the same way for most titles) I didn't worry about it too much,

But now that I'm home a lot more often and with considerably less plans, I decided to try to hand wire one with some switching diodes and some tact switches. 

The keypad doesn't work. I followed the attached schematic I found through Google. I decided to open up one of my original ColecoVision controllers to see if there was something I may have neglected, and it appears to my eye that the schematic I used is wrong. The diodes on the actual circuit board appear to be facing the opposite direction. Is this in fact my problem? I just want to make sure I'm not replacing 22 or so diodes for nothing. 

The diodes are backwards on this schematic. Here is another one from ChildOfCV:

StandardController.pdf

 

[Nateo]

Damn. That's gonna be a real pain in the ass to desolder those diodes.

[doubledown]

I've never hand wired an entire diode array before.  When I build a controller that includes a full keypad, or more than only 3 or 4 keypad inputs...I just install a donor controller PCB to wire to.  If a particular controller only has, for example, the 1, 2, and # buttons, then I will just hand wire in the few diodes, and forgo the donor PCB.  Additionally with a couple more wires, and a few more diodes, you can add the Purple & Blue Super Action buttons to controller too if you want.  

[Nateo]

9 hours ago, doubledown said:

I've never hand wired an entire diode array before.  When I build a controller that includes a full keypad, or more than only 3 or 4 keypad inputs...I just install a donor controller PCB to wire to.  If a particular controller only has, for example, the 1, 2, and # buttons, then I will just hand wire in the few diodes, and forgo the donor PCB.  Additionally with a couple more wires, and a few more diodes, you can add the Purple & Blue Super Action buttons to controller too if you want.  

Is there a schematic anywhere of specifically the Super Action Controller?

[doubledown]

Possibly/probably (not that I have a link to), but I just know it as:

 

Purple button - wires 1, 2, 4

 

Blue button - wires 1, 3, 4

 

So, for example, the purple button needs connection to each of those wires (1, 2, 4), through a diode each, on one side of the switch (usually NO), and wire 5 as the "common" on the other side (normally COM).  As a reference (from your previously posted schematic with the diodes show backwards), Keypad 1 needs connection to wire 4, through a diode on one side of the switch, and wire 5 as the "common" on the other side...same concept as all of the other 12 keypad buttons, as the extra 2 S.A. buttons are basically wired as the 13th and 14th keypad buttons.    

[Nateo]

Well, I finally got the hand wired keypad working! I decided to just do it over given that desoldering and resoldering all those diodes would have been way more of a pain than just starting from scratch.

 

Now comes the question of: what should I house it in?

 

[doubledown]

Congrats on getting it working. 

 

For the housing...it really depends on what you're going to do with it.  Do you want it built into a controller, or do you want to house it as a separate unit like the old Champ Adapters?  Additionally are you going to use additional buttons/caps with the tactile switches...or will they be the buttons that you manipulate...as they are?  How concerned are you with ergonomics...or is this just a simple test of functionality?  Lots of questions...lots of options.  Go nuts...and have fun!