As I am planning a blog post of every portable I have built yet, I want to show off the first of my Raspberry Pi portables. It uses a Raspberry Pi A+, a 4.3 inch composite screen, a PAM8403 audio amplifier, and a USB Hub with a WIFI stick for internet access.
The lcd, which is just from a cheap backup camera set, requires 12v, and its power circuit unfortunately was not compatible with the common 5V mod for these displays, I decided to include a 12v step up regulator, since efficiency was not a main objective of the portable (I just wanted it to work :).
The battery and its circuitry is from a 6000mah powerbank, which works okay, but it won’t work reliably for charge&play. I used a TPS2113A power multiplexer to try to solve this issue, and after some tweaking with the current limit, it kind of worked. When the powerbank does not supply power, it shuts it self off, so before unplugging the charge cable the powerbank circuit needs to be activated again by pressing its power button to avoid it shutting down.
The buttons directly connect to the Pi’s GPIO pins, where the retrogame script from Adafruit turns the input signals into keyboard presses.
Originally I used my very first Pi in the build, a Pi Model B Revision 2, but unfortunately it died in the process of building this unit (I accidentally connected the power leads backwards).
The first version of this project was a wooden handheld, my very first portable. I decided to take it apart and rebuild it, as it did not work correctly and playing games was almost impossible.
If you are curios how my very first portable looked like, I made a guide on Instructables (but keep in mind I was only 12 years old when I built this and wrote the guide): https://www.instructables.com/Wooden-Raspberry-Pi-Handheld/
As always, leave feedback and share if you liked the project.