PicoPocket

PicoPocket

PicoPocket is a handheld device that works on either the Raspberry Pi Pico (RP2040) or Raspberry Pi Pico 2 (RP2350). It's based on the Picopad schematic, and operates on the PicoLibSDK by Miroslav Nemecek.

Before diving in, take a look at the bill of materials and asks yourself if you are up for it? You need to be adept at 3d printing and finishing, and soldering 0603 sized SMD components.

Licensing: My PCB files and STLs are released under The Unlicense. Everything else retains the licenses assigned by their creators. I take no responsibility for anything. I am not linked in any way with the open-source gaming console Picopad.

1 x Waveshare 2inch LCD Display Waveshare

1 x 602550 Polymer Lithium Battery AliExpress

1 x Pi Pico RP2040 or RP2350 AliExpress

1 x Ghxamp Mini Speaker 8Ohm 1W - 34.8mm*11.2mm*6.0mm AliExpress

1 x Double Row Female 2x6Pin Right Angle Pin Header AliExpress

1 x G-Switch Card Slot MicroSD - GT-TF003-H0185-01 LCSC

1 x MOLEX PicoBlade(MX 1.25) - Mfr. Part #532610271 LCSC

9 x Buttons - hanxia HX TS5220A 160gf LCSC

1 x Slide Switch - Shenzhen Kinghelm Elec KH-SS12F23-G6 LCSC

1 x 0603 LEDs 4 colors AliExpress

2 x Schottky diode 1N5817 AliExpress

1 x TP4056 - SOP8 AliExpress

1 x NPN Transistor MMBT2222A AliExpress

3 x 0805 100nF SMD Ceramic Capacitor AliExpress

1 x 0805 0.4 Ohm SMD Resistor AliExpress

5 x 0603 SMD Resistors x 5 values (See Schematic) Aliexpress

4 x M2 x 16mm Flat Head Hex Socket Screws Amazon

1 x Silicone Rubber Sheet Thickness 0.5 AliExpress

1 x Clear Grass Trimmer Line Amazon

1 x Micro SD card 32gb Amazon

Other bit needed :

Kapton tape, Hot Glue, Sand Paper

A Soldering iron + Solder Wire 40/60 + Solder Flux + Isopropyl

The custom PCB can be ordered from a PCB fabrication manufacturer Like JLBPCB : Gerber File Zip (Use default PCB board settings. 1.6mm thickness etc. Just upload the gerber zip and order)

Design files like the STL's, gerbers, schematic, etc. can be found on the GitHub Page for this project

This is a project for people who are adept soldering SMD electronics. With that in mind, I'll be brief on this section..

I personally start on the battery side of the board first. The Schottky diodes need to be the right way around, as do the LED's. LEDS colours I use are red for CHR (charge), green for FULL, orange for SD, and yellow for USR (the user LED).

When attaching the Waveshare display, you need to first completely remove the rear PH2.0 8PIN interface. It is not needed. You then solder an 8 pin male header to the screen, and remove the plastic spacer. The screen needs to be 1mm from the PCB. I used some slightly thicker (1mm) foam double sided tape under the screen.

You will also have to enlarger the upper right screen hole (see image 2 above). I drill mine out with a Dremel drill. I messed up the screw alignment slightly... oops

Attach the speaker with hot-glue, and the battery with a bit of double sided tape.

The STL files are on GitHub

I've used eSUN Bone White PLA+ filament for the main body of the case. Other colours used were black, grey, yellow, orange red & brown PLA from Eryone. The case was printed on a Bambu Lab A1 mini 3D Printer.

The Base

The base is printed in what you might describe as the "correct" way. I used a wide 8mm brim to stop corner lift. The other setting changes are :

1. System preset = 0.16mm Optimal
2. Brim enabled - Outer brim only 10mm
3. Supports enabled - Snug
4. Bottom surface pattern Hilbert Curve
5. Seam position = Back

You could also slow down the bottom layer print speed for a better finish. After printing the base, it's bottom curves can be sanded to a smooth finish using grits from 240 to 1500.

The Top

This is printed in the "wrong way"... why? Just accept it and move on. Mostly default setting, with the following changes:

1. System preset = 0.16mm Optimal
2. Brim enabled - Outer brim only 10mm
3. Supports enabled - Default
4. TOP surface pattern Hilbert Curve

You could also slow down the top layer print speed for a better finish. After printing the top, carefully remove the supports and brim. This takes a while to do well, as does the sanding of the base.

The Buttons and Thumbs stick

System preset 0.16mm Optimal, again with brims (8mm) and then sanded with grits from 240 to 1500. If you want it to feel like it was injection moulded, you have to put the work in.

Alternate Designs

Some alternate case designs are available on TinkerCad : LINK

To get 4 PLA colours on the speaker insert, you need to use the painting function in BambuStudio. A combination of triangle painting and the fill bucket and you can get the 4 PLA colors assigned to the insert. It takes some practice. When it's ready and AMS lite is all setup, you print with a 2mm brim. After printing, leave the brim on, and carefully superglue the insert into the case

I glue light pipes for the LED's using 1.3mm clear lawn trimmer line. This generally goes wrong, and you have a whole bunch of sanding and buffing to make it look like you didn't get superglue everywhere. Good luck !

I used some 0.5mm silicone sheet to dampen the button's clickiness. This doesn't have to be that accurate. Just cut some sheet as shown in the picture. Without it, the buttons are probably going to have too much rattle, although you could adjust them.

Due to some rushed design choices, the top 2 screws don't have very good anchor points. Basically, the case should hold together fine if you screw it together once and perhaps use a little glue or two part epoxy resin (glue) on ends of the top 2 screws. They worked for me anyway.

Just download the SD card contents for Pi Pico 1 or 2 from PicoLibSDK by Miroslav Nemecek and put it on your SD card. The LOADER.UF2 file needs to be uploaded directly to the Pi Pico, then everything else goes on an SD card. There are versions for the Pi Pico 2 Arm & RISC-V modes. I've been using the Picopad 2 Arm version for my RP2350 PicoPocket.

Conclusion

You could of course make your own device using the Picopad Schematic like I did, or buy a Picopad or Picopad kit. It's a fun development platform that may get further updates that utilise the more powerful Pi Pico 2 in the future. Even as it stands, it has a lot of fun things for a non coder (like me) to mess around with. Many thanks to the software and hardware designers who worked on Picopad.