Mini Arcade Machine for RetroPie

Build your own arcade!

My take on a mini arcade build for RetroPie. Will add description and build instructions/links to parts later if there is interest.

This is a fairly advanced build. Could use a few tweaks to improve (might do that at some point), but overall was quite pleased with the end result.

Highlights:

• A two player system! playing with a friend is incredibly fun
• Integrated sound with ground isolation
• Haptic feedback in joysticks
• Real coin insert button made from a real dime (to look similar-ish to mini quarter)
• Functional coin “reject” button remapped as start button
• Live marquee which really ties the entire piece together
• Fun lighting using Neon Electroluminescent (EL) Wire
• 10 mappable action buttons in total per player (including the coin and reject/play buttons)
• Used RetroPie platform on raspberry pi 4b
• Supports wireless controllers and keyboards
• Has a mini keyboard tray for paired Bluetooth keyboard. Useful when emulating DOS games.

Parts list and links:

FYI, this was a project I put together mainly using parts I had laying around from other project that I had torn down. Rather than seeing these guys on a shelf sitting I put them to good use. So some parts may be unavailable right now such as the exact speakers. But I'll go ahead an upload the raw CAD files also so folks can modify to fit other audio choices. The audio I have is only mediocre. I recommend looking around for some upgrades and add a small woofer. 

• Raspberry Pi 4b 
• 32GB micro SD card
• I recommend a 5A USB-C power supply such as https://www.amazon.com/dp/B07H125ZRL/ref=emc_bcc_2_i
• Install retropie - https://retropie.org.uk/
  • You can do this easily using the raspberry pi image installer tool found here - https://www.raspberrypi.com/software/
• I used two 2-inch 4ohm speaker (currently unavailable at amazon but any similar speakers will do but may require modifying the mounts) https://www.amazon.com/gp/product/B00LSF603M/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Stereo audio amplifier - https://www.amazon.com/gp/product/B08RDN58SZ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Audio ground loop isolator - https://www.amazon.com/gp/product/B019FC6ZQQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• 7.9 inch bar monitor - https://www.aliexpress.us/item/3256802114437873.html?spm=a2g0o.order_list.order_list_main.61.433a194dKTd8a0&gatewayAdapt=glo2usa
  • I used this mod for marquee - https://github.com/rinalim/PieMarquee2
  • Install it after installing retropie
  • I had to rotate the media player video output. Will add code references for this. 
• Main screen is using - https://www.waveshare.com/5.5inch-hdmi-amoled.htm
  • This screen is a little on the small side and overkill for what you need but works and is fun still. I used it as I had it laying around from another project and put to good use. 
  • I'll upload CAD files so you can mod this build to use other monitors if you would like. 
  • This screen requires to modify the retropie settings to deal with screen rotation. I have gone through the trouble and will add reference code but some of the quick menu screens can't be rotated. Was a pain for me to figure out the rotations as some of the more straight forward methods did not work for some reason. Just FYI. 
• Two Xbox elite joysticks - https://www.aliexpress.us/item/3256806117161331.html?spm=a2g0o.order_list.order_list_main.31.433a194dKTd8a0&gatewayAdapt=glo2usa
  • Note that the joysticks are analog and require an analog to digital converter. I used two esp32-c3 devices for this. One for each player.
  • Another note, this joystick uses hall sensors so be cautions when wiring power, ground to get the connects correct else you will blow the sensors as these are not resistor pots. 
• Two ESP32-C3 micro controllers to function as the A2D joystick converters - https://www.adafruit.com/product/5405
  • Any microcontroller with 2 A2D inputs and 4 digital outputs will work (for one player, two controllers or double those pins for two players)
• Two of these zero delay controller boards - https://www.amazon.com/gp/product/B00UUROWWK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• 20 low profile choc switches. I recommend getting the blue clicky ones - https://www.aliexpress.us/item/3256803025285973.html?spm=a2g0o.order_list.order_list_main.16.1a571802Ax35O7&gatewayAdapt=glo2usa
  •  Order a few extra in case you mess up soldering
• You will need various micro-usb to usb-a connectors to power the screens
• You will also need cables for connecting the micro, to mini and regular hdmi. I bought from here - https://www.aliexpress.us/item/3256802388498848.html?gps-id=pcStoreLeaderboard&scm=1007.22922.271278.0&scm_id=1007.22922.271278.0&scm-url=1007.22922.271278.0&pvid=ca73be95-bf5b-48f7-a408-80619e172569&_t=gps-id%3ApcStoreLeaderboard%2Cscm-url%3A1007.22922.271278.0%2Cpvid%3Aca73be95-bf5b-48f7-a408-80619e172569%2Ctpp_buckets%3A668%232846%238115%232000&pdp_npi=4%40dis%21USD%210.79%210.74%21%21%210.79%210.74%21%402103248517071182394094773e10ac%2112000021219964939%21rec%21US%21702203193%21&spm=a2g0o.store_pc_home.smartLeaderboard_6000743633505.1005002574813600&gatewayAdapt=glo2usa
• For the coin “play” button I used this led - https://www.amazon.com/gp/product/B01DC0J0WS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1
• For the electroluminescent wire I used - https://www.aliexpress.us/item/3256802567110977.html?spm=a2g0o.order_list.order_list_main.22.1a571802Ax35O7&gatewayAdapt=glo2usa
  • I would skip this!!! It looks kind of cool but is a pain to solder… I think some various RGB LED's could look better. Again will add CAD files soon so you can mod. The main key panel has cutouts for these wires however I would ditch that and think of something else that's easier to wire and assemble. 
  • If you do skip this then you will want to fill in the gaps in on the button plate with some accent color filament or something. Get creative. 
• For the haptics inside of the joystick it just vibrates whenever you're moving. Not as dynamic as true haptic feedback. Still fun though. I used these - https://www.amazon.com/gp/product/B0C6D9S9MB/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Various M4 and M3 bolts with nuts and a few M4 and M3 threaded inserts
• Two dimes

Software / code:

• to be added…
• will upload code sometime in the next week for microcontrollers and the modifications to retropie that are needed

Okay I think that's all the parts… If I missed something will update. I don't have time to put together a full build guide this weekend. Will try to chip away at adding some guidance on the build over the next week. 

Enjoy!

Design by aaron.willey on MakerWorld (license: BY).