Arduindo Blitz hobby handheld console

Very simplistic handheld “console” I made for my kids. 

You can find an example game here: https://github.com/elyvilon/FoP2/

Printing instructions

I recommend PETG or stronger but you probably can use PLA too. Using 0.2mm layer height print with 5 tops and 5 bottoms to make the case solid. For the bottom part you can print either the one with battery compartment and use supports or print the bottom and battery compartment separately. I recommend to print the buttons solid as it does not increase material usage or time too much but makes a nicer feel to them. The parts have somewhat tight tolerances but they should be very doable for any reasonably dialed in printer. For the sunken holes you can use supports or sacrificial layer but I managed to print them without either.

Required materials

• Arduino Nano without pin headers installed
• 20x4 character LCD with I2C module
• 4x4x9mm sliding switch
• 6pcs 6x6x6 buttons 
• standard passive buzzer
• resistor/trimpot for buzzer
• 9V battery snap connector
• 10pcs M3 heat inserts
• wire
• heatshrink tubing
• 4pcs female dupont connectors
• 4pcs M2x4 hex head screw
• 4pcs M3x16 hex head screw
• 2pcs M3x8 hex head screw
• 4pcs M3x4 hex head screw

Wiring

I don't have a proper wiring schematic but it isn't too complex. Just connect battery snap + to VIN through the switch, - to GND and the rest as follows:

• Up button → D2
• Down button → D3
• Left button → D4
• Right button → D5
• Start button → D6
• A-button → D7
• Buzzer → D8
• LCD SDA → A4
• LCD SCL → A5
• LCD VCC → 5V
• LCD GND → GND

All grounds go to a common ground. Add a suitable resistor depending on the desired volume (test with breadboard) or better yet a trimpot in the buzzer positive wire. 

Assembly instructions

1. Insert the M3 heat inserts to the top part of the case and the battery compartment. Cut off any excess plastic. Clean the button holes of any seams and other imperfections and test that the buttons fit the holes. The buttons should be snug but still move freely. If you have trouble getting the buttons in you can try slightly scaling the buttons smaller.
2. Screw the LCD to the top with M3x4 screws.
3. Glue the battery compartment to the bottom part of the case (of course you skip this step if printed as a single piece.
4. Install all electrical components to the proper places and solder the wiring. There is ample room for wiring but try not to use too long wires, route them properly and use zip ties. Don't forget the heat shrink tubing. It seems at least the Nanos from Aliexpress have slight variations in the mounting holes but it should hold even with 2 screws if all the holes don't align properly. Drill the holes a bit larger carefully if the screws don't thread in them.
5. Push the power switch on the slider. You should not need glue as it can easily seize the entire switch.
6. Connect the LCD, insert buttons to the top (A-button is keyed) and d-pad pin to bottom part.
7. With the top facing down so the buttons stay in place put the two pieces of the body together and secure from the backside with 4 M3x16 screws. Try not to pinch any wires between parts. Insert battery and secure the battery compartment lid with 2 M3x8 screws. If you have trouble with the buttons you can try scaling them down a bit. You can also finetune the d-pad with the height of d-pad pin.
8. Done! Load in some software and test.