Building the Picade Mini Part I

by Jon

It was over a year since the Picade Kickstarter ended that I finally got my Picade Mini kit in the mail. Others have reported some issues with these early kits, but with the holidays I wasn’t able to crack open my box until this weekend.

Picade Mini PanelsFirst up let’s take a look at the instructions. We have a bunch of very nice wood panels and a system of plastic wedges (fixed joints) with bolts and nuts to hold everything together.

Picade Mini BottomHere’s what the bottom looks like with the plastic wedges bolted on. Notice the edges of the board, which feature a jigsaw puzzle-like pattern for connecting them to the other boards.

Picade Mini Bottom and SidesNext I’ve attached the side and front panels, and it’s starting to look like an arcade machine already! This is going to be a quick build at this rate.

Picade Mini with the screenThe instructions call next for the screen, so I go ahead and pop that in. But before I get ahead of myself, I know that others have had problems with their screens, so I go ahead and plug it in to see what’s what. And sure enough, my screen outputs double- the whole of the input is mashed up at the top of the screen, with it repeated at the bottom. Damn.

Undeterred, I continue forward with the instructions and decide it’s high time to build the controls. I pick out the design to go under the acrylic and install the joystick and buttons to the control board. Everything pops in pretty easy, and now it’s time to see how this thing mounts to the rest of the cabinet.

Dremeling away the fixed cornerHere I run into my next issue: there’s another set of plastic wedges for securing the controls, but as other builder have discovered, the right-most buttons interfere with the placement of the wedge. So, looks like I need to grind down that wedge a bit- what better a time to test out the new Dremel I got for Christmas.

Reshared wedge under the control boardI make a couple quick marks on the wedge with a pencil, then out on my patio in the rain (hey, it’s Seattle) and away we grind. Not ten minutes later, and the modified wedge fits perfectly!

Picade Mini control panelFlip the panel over, and it looks great. There’s a variety of colored buttons in the kit, two each of red, blue, green, and yellow, along with four black, and a red ball on the joystick. At first I can’t decide on a scheme I like, but then I dig into my stash of joystick parts, and come up with a white joystick ball and decide to mimic the Xbox 360 controller with my layout (I am an Xbox guy after all).

Picade Mini with the control panel onSince the screen will probably need replacing, I can’t bolt it in permanently, and I can’t finish up the top marquee just yet. But even without it, it looks good with the controls and the other cabinet buttons installed.

I move on to the wiring, which is a pretty straight forward affair of connecting all of the buttons and the joystick to the Picade’s custom PCB, and installing the speakers on the inside of the cabinet. Others have reported problems with the wiring looms, and to be sure I test them all first, and end up fixing just one crimped connector in the whole set.

Picade Mini broken screen 2Then I plug the PCB into my laptop, and sure enough, it appears as an USB keyboard. By default the joystick reports as arrow keys and the buttons as the default controls for MAME. Unfortunately this means unnecessarily using the Control, Alt, and Shift keys, and I don’t want to enter some command by mistake (on the full-size Picade, you can hit Control+C by hitting two buttons at once, which would be an annoying surprise in the middle of a game). So following the instructions of others, I fire up the Arduino IDE and reprogram the buttons to my liking.

Picade Mini broken screen 1 But now I’m little stymied. I could go forward on several fronts, but it’s already getting a little cramped in the cabinet and with the broken screen I don’t want to put too much in the way before I replace it. Once the double screen gets fixed though, the cabinet should be easy to finish off. I just need to attach the control board, the top marquee, and finally the back door.

After that, I can start focusing on the brains of the machine, and the further customizations I have in mind. Stay tuned!

/jon

P.S. Since the creators of the Picade got lots of extra backing money, I think they overgeneralized the design- great for folks who don’t want to actually use a Raspberry Pi themselves, but not so great for those who do. Namely, they don’t address the Pi’s missing power switch, which in my experience with emulators means that without a keyboard on hand, if a game freezes and you hard power down, the Pi’s SD card gets corrupt and you can’t boot anymore.

There’re plenty of 3rd-party hardware solutions to this well-known problem, and it’s a little disappointing that the Picade guys didn’t integrate one into their design. Also, you have a power supply for the monitor alone, with the expectation (in the instructions) that you need to add a separate power supply for the Pi, then inelegantly run two power lines out the back, or hide a power strip inside. That’s another thing- by default you either have to run out any cables (say network and USB) out slots in the back, or keep opening the back door to access anything.

With all that in mind, I’m going to install my own Ethernet and USB ports, as well as a power jack and an actual power switch, a single one for a single power supply that powers the whole cabinet. Overall, I think I’ll end up with a pretty sweet machine if I can get the screen replaced, but this project is definitely not the “just supply the Raspberry Pi” weekend project I thought it’d be.

Update (01/23/14): Part II is up!

Update (03/05/14): See the video: Picade Mini build running RetroPie.