RCKid mk3

This is the third iteration of the RCKid handheld gaming device for kids. The handheld is a homage to 90's handheld consoles with limited and easy controls, and swappable cartridges that offer both software and hardware extensibility.

Technical specifications:

• powered by RP2350 (2x ARM Cortex M-33 or RISC-V, 512KB RAM)
• 320x240 IPS LCD screen at 60fps and 65536 colors (framebuffer and tilemap modes)
• mono speaker and stereo headphones out
• 3 axis accelerometer, ambient light sensor
• rumbler
• DPAD, A, B, Sel and Start keys with own backlight, Home and dedicated volume buttons
• SD card for large file storage
• ~1000mAh Li-Pol battery for ~10hrs of operation

Cartridge specifications:

• flash up to 16MB
• 10 GPIO pins
• 3V3 capable of 600mA loads
• optional PSRAM support (up to 8MB)

Externally, it is almost identical to the version 2 built upon RP2040, but internally uses the new RP2350 chip instead. This allows both simplifications in the design (no need for AVR coprocessor because of higher pin count on RP chip) as well as improvements (less RAM pressure, possibility of external RAM in cartridges and more CPU raw power that makes more things possible).

Directory Structure

• cartridges folder contains specific cartridge ROMs that can be build as part of RCKid
• datasheets contains copies of datasheets of the hardware used in RCKid
• hardware contains hardware related files, such as schematics, PCB layouts and case drawings
• libs holds mostly 3rd party libraries that are part of the RCKid SDK
• sdk contains the librckid SDK library files and all backends

Building

Windows & WSL Ubuntu are supported for both development and fantasy console, anothough linux is much more tested. On linux, the setup-ubuntu.sh must first be executed which installs all the required packages and sets up subprojects, etc.

This step is necessary for windows development as well as it installs the rpi-pico sdk and raylib for fantasy console.

RCKid uses cmake so the following builds the fantasy console & all cartridges on linux:

mkdir build-linux
cd build-linux
cmake ..
cmake --build .

To build RCKid for the device (mk III in this example), do the following:

mkdir build-mk3
cd build-mk3
cmake .. -DARCH=ARCH_RCKID_3
cmake --build .

And finally, under Windows, enter the Visual Studio Developers prompt and then type:

mkdir build-win
cd build-win
cmake ..
cmake --build . --config=Release

Build Argumente

RCKid's build can be customized using various arguments, such as the -DARCH showed above to build for a particular architecture. This section lists other useful build arguments:

• -DRCKID_WAIT_FOR_SERIAL runs RCKid to the end of the initialize() function and then waits for a single byte to be sent on the USB-Serial. This is useful to ensure that a serial monitor on the pc is up & running before RCKid's firmware starts doing stuff so that it can be captured properly.

SDK

The SDK library is at the core of RCKid as it provides an abstraction layer over the console's hardware. Furthermore, it makes RCKid also a fantasy console by being able to run on a PC for most of the features. Therefore the SDK comes in two folder, rckid where the common interface resides, and backends where specific implementation for the various hardware versions and fantasy consoles is implemented.

For now, fantasy console via raylib (Windows and Linux), RCKid mk3 (RP2350) and RCKid mk2 (RP2040) are supported. Once mk3 hardware is available the mk2 version will be retired.

Attribution

• doxygen theme: https://github.com/jothepro/doxygen-awesome-css
• icons are from flaticon, for detailed attribution, please see ATTRIBUTION.md file