PioNeer

A handheld gaming console built on the Raspberry Pi Pico 2 (RP2350). ECE 362 final project.

Overview

PioNeer is the firmware for a self-contained handheld game console. The device boots into a graphical launcher that reads game binaries from a microSD card and displays them as a grid of selectable tiles on a colour TFT screen. Selecting a game side-loads it: the launcher copies the binary into flash, locates its entry point, and reboots the microcontroller directly into the game.

This repository contains the launcher/bootloader firmware and the hardware drivers that back it (display, input, audio, addressable LEDs, and SD storage). Individual games are separate RP2350 binaries placed on the SD card rather than part of this project.

The name is a nod to the RP2350's PIO (Programmable I/O) block, which is used here to drive the WS2812B LED strip.

Hardware

The firmware targets the RP2350 (Raspberry Pi Pico 2 class) microcontroller and drives the following peripherals. Pin assignments are defined in include/config.h.

Subsystem	Device	Interface	Notes
Display	ST7796 TFT LCD, 480x320	SPI0 @ 40 MHz	Rendered with LVGL
Buttons	A / B / X / Y face buttons	GPIO 34-37	Timer-based debouncing + edge interrupts
Thumbstick	Analog joystick + push switch	ADC ch0/ch1 (GPIO 40/41), switch GPIO 39	Menu navigation and select
Audio	Speaker driver	PWM on GPIO 38	Two-channel wavetable synth
RGB LEDs	10x WS2812B addressable strip	PIO on GPIO 9	Driven via the RP2350 PIO
Storage	microSD card	SPI1	FatFs filesystem

Features

• SD-card game launcher. On boot the firmware mounts the SD card, scans the games/ directory, and renders each binary as a coloured tile in an LVGL grid menu. macOS metadata files are filtered out automatically.
• Side-loading bootloader. Selecting a game reads the binary into RAM, erases and programs it into flash at a 1 MB offset, scans the image for a valid RP2350 vector table (stack pointer in SRAM, program counter in flash), and jumps into the game via a watchdog reboot.
• Wavetable audio. A two-voice PWM synthesizer with sine, sawtooth, square, and triangle waveforms, updated from an interrupt handler.
• Addressable RGB lighting. WS2812B strip driven from a PIO program, with RGB/HSV colour control, per-pixel brightness, and animated effects.
• Power-on self-tests. Built-in routines exercise the display, LED strip, and audio path (see src/self_test.c).

Build and flash

The project is built with PlatformIO against the Raspberry Pi Pico SDK. The environment is defined in platformio.ini (board = proton, framework = picosdk), and pulls in LVGL and a FatFs SD-card library as dependencies.

# Build
pio run

# Flash and monitor (configured for a picoprobe debugger)
pio run --target upload
pio device monitor --baud 115200

The default upload and debug tool is picoprobe; serial logging runs at 115200 baud.

SD card layout

Place compiled game binaries in a games/ directory at the root of a FAT-formatted microSD card:

/games/
  game1.bin
  game2.bin
  ...

Each game must be a standalone RP2350 binary linked to run from the 1 MB flash offset that the launcher programs it to.

Controls

• Thumbstick — move the highlight between game tiles in the menu.
• Thumbstick press — launch the highlighted game.
• A / B / X / Y buttons — available to games as face inputs.

Repository structure

platformio.ini      PlatformIO build configuration (board, framework, libs)
filter_libs.py      Build hook that skips SIMD/RISC-V assembly variants
include/            Public headers and hardware pin/config definitions
  config.h            Pin map and board configuration
  lv_conf.h           LVGL configuration
src/
  main.c              Boot sequence and menu loop
  ui.c                LVGL launcher menu and the side-loading bootloader
  spi_display.c       ST7796 TFT setup and LVGL flush callbacks
  adc_joystick.c      Analog thumbstick and switch
  gpio_buttons.c      Debounced face-button input
  audio.c             PWM wavetable synthesizer
  led_strip.c         WS2812B / PIO LED driver and effects
  sd_api.c            FatFs SD-card wrapper (mount, files, directories)
  self_test.c         Display / LED / audio power-on self-tests
  ws2812.pio.h        Generated PIO program for the LED strip
not_compile/          Standalone input-test harness (excluded from the build)