How-to: Picade 12" Screen + HAT + Single Power Source + On/Off Buttons!


Interesting, I actually ended up ordering the ATXRaspi from the USA as there were no EU vendors (I’m in Ireland).
But this OnOffShim seems cool, but can you branch out the status LED? so you can connect it to the Momentary switch’s LED and get those cool blinks :)

One thing tough. Make sure you check the LED voltage on the switch. most of these, as they are done for cars, have 12v LEDs, and I suspect you will only get 5V from Pi or OnOffShim, which means led will not be so bright.

I’ve tried to track down momentary switches with 5V LEDs but its proven difficult, all I can find thats <12v is 3V and to power that from Pi I need to add a resistor… which goes against the “Simplicity” that I want for my, or should I say Luis’ Picade setup which is the one I am aiming for (Thanks again Luis) :)


Not sure about the LED blinks, I suspect not. What do they indicate, is it disk activity?


Not sure what or if OnOffShim has this, but ATXRaspi branches out connections to switch LED, when you press the button the LED comes on, then the board sends pulses to switch so it blinks in differrent speeds to show you what ifs doing (boot, reboot, shutdown)
Check out the install guide video here (its starting when everything is connected and you are turning on Pi for first time and installing script to run ATXRaspi)


Mine is a momentary switch because of the way ATXRaspi works.


@radiokid, the LED on the OnOff SHIM is used to indicate button press, as well as, using our clean-shutdown software flash throughout the shutdown process.



I got my switch when I bought my ATXRaspi from lowpowerlab in the USA.




Hi All,

This is a great thread, really useful! I have just bought my first Picade and I’m really keen to make some of these brilliant mods, however I’m a complete DIY and electronics noob! I would really like to mirror @Luis mods, i.e. Single power source on button, 12.1" screen and some theme changes.

I’ve bought the 12.1" screen and power board, the step down voltage regulator, also the ATXraspi board and momentary switch. Just need some guidance on wiring it all up!

So first basic question what wires and connectors do I use for electrical wiring? Do you know where I can get some? Also I’m unsure of which DC female connector to use for the cab, as they all seem too short to fit through the side panel and be fixed against the inside?

Regarding the theme, I’d love to have a super mario themed cab but don’t know where to find the artwork and how to get it printed to size, I particularly like the artwork surrounding the screen @Luis! Any guidance?

Once I’ve got the above sorted which I’m sure will take me a while I’d also really like to add some led buttons. Found a good thread which led me to the Seimitsu screw in buttons which look great However I have no idea how to wire these, or whether I can still use the original wires provided with the picade?

Sorry for the basic questions, but just starting out with arcade cabs and electrics and any guidance would be very much appreciated! Been looking around on forums and this is one of the best threads!




Seems you have some questions like I had in the beginning. but this topic has (almost) all the answers.

You mayneed to by a 12v barrel jack cable with only a male plug to branch out the 12v coming in and going into the LCD Driver board. something like this:

The jumper cables going from the ATXRaspi to the Raspberry (to send shutdown/boot signals) as per LowPowerLabs recommendation should be good quality to avoid problems, and if powering Pi via GPIO from ATXRaspi, you should also use high grade jumper wires.

depending on the power source you select, your female dv jack in should match the power source. most say the plug is either 5.5mmx2.1mm or 5.1mmx2.1mm so you should get a female jack panel mount that matches. something like this:

You then onlu need to drill 2 small holes on the back panel of the Picade, one to fit the switch, another to fit the dc socket.

As for artwork, try and have a look at this topic:

Hope this helps (and that I got it right) and dont forget to post pics of your completed setup :)



I would suggest that those sockets are not suitable as they need a rating the same or greater than the PSU. I would be surprised if they are rated at more than 1A.




Hi Fcalcada & Paul,

Thanks very much for the response. If I go for the DC connector you used Paul what A rating is this? Would this powerpack be ok even if it is rated at 5A ? Paul how did you fix the DC connector to the cab? I can see you countersunk it, did you drill a hole the width of the connector from the outside of the cab and then use a slightly larger flat head piece from the inside part way through the panel so you can fix the nut?

For the jumper cables I’ve bought these, will they be ok?

Fcalcada many thanks for the link to the artwork, there’s lots to look through! Can’t wait to share the final picture. Not too many screen bezels though, may research making my own :/!

Any thoughts on the cabling for led buttons? Can I use the existing cables with the picade with the Seimitsu screw in buttons or are extra cables needed for the leds?

Thanks for the advice really appreciate it!




Hi David

The DC socket I used was rated at 5A so would be fine for your PSU and I used exactly those cables for connecting the ATXRaspi. However I didn’t power the Pi through the GPIO connector so if you plan on doing this then you will need a more substantial jumper for the supply connections. For your PSU in the link it says it has a 2.5mm connector so you want the second connector in my post above.

To mount the connector I did exactly as you describe. Drill a hole the size of the threaded part from the outside then use a flat wood drill bit to countersink from the inside. You just have to be careful when drilling from the inside that you don’t go too far. I used a hand drill and made the holes before I assembled the cabinet.




Cheers Paul,

Thanks for the heads up on the power supply connector will make sure I get the right one, terrified about drilling into my new picade but we’ll give it a go!

I’ve ordered a ATXRaspi with a female USB so planning on powering the pi using a USB A to Micro USB short cable, that should work huh?

Thanks again for the help!



Yes that’s how I powered mine via the USB.

Let me know if you want any close ups inside mine and I’ll take a few more pictures.




Hi Paul,

Good to know I’m on the right track! Thanks for the offer of pics I’m certain I’ll need them once all the parts arrive.

So next newbie electrical question, sorry about this! I noticed that the voltage step down converter I have and the connector are both DC however the power pack I am looking to purchase is AC, does that matter?

Also I’ll need to crimp on some female spade connectors for the wire from the 12v DC into the converter and the wire out from the 12v current into the 12" monitor. As there is only one positive and one negative terminal on the DC connector can I put both cables (step down converter and monitor power cable) into one single female spade connector?



There was another question, I like how you have fixed your board with the standoff spacers. How did you fix those to the picade? Did you drill small holes through the base place and fix with a screw from the underneath?




The PSU in the link has a DC output is that not the one your are buying? You cannot use a PSU with an AC output it must be DC.

Yes you can combine the cables as you suggest.

The mounting screws are recessed on the underside of the cabinet.




Cheers Paul!

Aha! Was being stupid, right the input for the power pack is AC but the output is DC…got it!

Thanks for the confirmation on the spade connectors and mounting screws. Think I’m ready to start once all the bits arrive! Sure I’ll have some more when I start putting it all together!

Thanks v much for your help so far!


@MrScruff Sorry for the late reply. I copied my build from @Dyltone and he copied his from @Paulcheffus build, so all the credit goes to them.
For your LED buttons I would take a look at Dyltones build. He used a USB LED with some sanwa translucent buttons and it looks great.


Hi Luis,

No worries at all! Thanks for the advice, I’m still waiting for the screen and a few other pieces to arrive before I start building.

@jarrah I did have a quick question, I bought the same DC power cable as you for the LCD controller board. What size DC connector is on the controller board is it 2.5mm or 2.1mm? Also the cable you linked has one black wire and a black wire with a white stripe, which one of these is the positive wire?




The wire with the white stripe is usually the positive.