Hello Shawn, sorry for this late reply - I had some family duties in the recent weeks, but things are becoming more relaxed ever day now.
If you configure the ControlBlock for SNES controllers. You should be able to going back and forth between SNES and NES controllers on the same connector. Actually, I built a NES-SNES-Adapter myself some time ago in the same way as you described above.
The GPIO schematics have always been in Supplementary Downloads on the official website:
A parts list and explanation of the circuit is on the blog post announcing the adapter:
Here is a higher quality image of the board:
AIUI the GPIO adapter is out of stock because it's been superseded by the ControlBlock:
( Note: I tried my hardest to make sure that these were the correct numbers through multiple measurements because I also need these numbers for myself, but use at your own risk since my calipers would sometimes give tiny bit different measurements... some may require a tiny amount of "give & take" so err on the side of "optimistic." )
I am using a digital caliper set to use the "mm" function.
Pi width is: 56.10mm
PowerBlock width is: 56.09mm
Distance between the top of the Pi, and the bottom of the Powerblock are: 10.85mm
PowerBlock thickness is: 1.63mm
Widest MiniUSB length: 7.96mm
MiniUSB height: 3.06mm
Edge of MiniUSB to end of PowerBlock 1 (Excluding the MiniUSB): 17.07mm
Edge of MiniUSB to end of PowerBlock 2 (Excluding the MiniUSB: 31.00mm
Brilliant, thanks Paul, that was just what I needed. I soldered my connections at the switch to make sure there were no frayed strands causing shorts and connected as you advised and all is working perfectly.
In case anyone happens across this thread with the same problem, the connections were as follows:
Switch ---> ControlBlock GPIO
( + ) ---> LED +
( - ) ---> LED -
NO1 ---> Switch +
C1 ---> Switch -
@mark1986 Thank you! I have two wires for every button on my arcade setup, as it came delivered that way with the Zero Delay Controller Card. But I'm planning to build an arcade stick for my PS4, then I'll use a daisy chain for sure ;)
Figured it out, sort of. Ended up just using the Gamecon GPIO module and getting the GPIO pin placement correct.
Unfortunately, the victory became pointless when I then moved to install the PiTFT 3.5" screen as the kernel that the adafruit-pitft-helper installs is something like RetroPIE 4.1.14 v7, where the newest version, that the gamecon GPIO driver works with is 4.4.something. (Sorry don't have it running in front me.) I can actually see it uninstalling the gamecon module when I run the pitft-helper scripts, and then can't re-install gamecon from the RetroPIE setup util...