Building a couple Pocket Pigrrl RetroPi 3D Printed Gaming Handhelds
I am building two customized Pocket Pigrrl’s for my daughter and niece. As a kid the NES system was mine, but my younger sister owned the original gameboy which I constantly stole from her on car trips so it seemed right that both our kids have little portable gameboy like devices. I am also hoping that this device will help keep mommy’s phone away from the children.
I started out by cutting down the half sized perma proto board and laying out the buttons for a 4 button pigrrl. I used my dremel to cut down the perma proto boards and then attached the 6mm tactile buttons onto the cut down proto board. Then I layed out the Raspberry Pi A+, PowerBoost 1000C and Audio Amp boards inside the case and started cutting some wire.
Next I wired up the switch and applied the heatshrink tubing, then I attached the wires to the audio jack of the raspberry pi and connected them to the PowerBoost.
I made a table of all the GPIO inputs on the Pi, and where they map to in the Pocket Pigrrl project:
| Wire # | Pin | Key | Connect to |
|---|---|---|---|
| 1 | GPIO 3V | N/A | Unused |
| 2 | GPIO 5V | N/A | PowerBoost |
| 3 | GPIO 2 | Key X | Perma Proto Controller |
| 4 | GPIO GND | N/A | Unused |
| 5 | GPIO 3 | Key Y | Perma Proto Controller |
| 6 | GND | N/A | PowerBoost |
| 7 | GPIO 4 | Key Left | Perma Proto Controller |
| 8 | GPIO 14 | N/A | Unused |
| 9 | GND | N/A | Perma Proto Controller |
| 10 | GPIO 15 | N/A | Unused |
| 11 | GPIO 17 | Key Right | Perma Proto Controller |
| 12 | GPIO 18 | Key Up | Perma Proto Controller |
| 13 | GPIO 27 | Key Down | Perma Proto Controller |
| 14 | GPIO GND | N/A | Unused |
| 15 | GPIO 22 | Key A | Perma Proto Controller |
| 16 | GPIO 23 | Key B | Perma Proto Controller |
| 17 | GPIO 3V | N/A | Unused |
| 18 | GPIO 24 | N/A | Unused |
| 19 | GPIO 10 | N/A | Unused |
| 20 | GPIO GND | N/A | Unused |
| 21 | GPIO 9 | N/A | Unused |
| 22 | GPIO 25 | N/A | Unused |
| 23 | GPIO 10 | N/A | Unused |
| 24 | GPIO 8 | N/A | Unused |
| 25 | GPIO GND | N/A | Unused |
| 26 | GPIO 7 | N/A | Unused |
I soldered all of the ground wires for the controller and clipped the unnecessary wires from the Pi GPIO cable.
The last step was to solder all of the controller buttons to the perma proto board and test that everything was working properly.
I downloaded the Adafruit RetroPi image and everything fired right up. I found that the up button was turning off the screen, so I cut the GPIO18 backlight trace on the back of both screens and the system is working properly, now it is time to load some ROMS!
