PM2040

An RP2040-based Flash cart for the Pokemon mini handheld. The RP2040 acts as the ROM chip of the cart.

Software Side

In order to load a game onto the cartridge, you first have a "convert" a ROM to a UF2 file.

Using the Online Patcher

You can use the online patcher tool to patch in a ROM (or even 2 ROMs when using the "2 in 1" firmware) into the ROM-less base UF2 firmware (note: pick the PM2040_BASE.uf file for the single ROM FW and the PM2040_BASE_MULTI.uf2 for the "2 in 1" FW):

• Single ROM patcher
• 2 in 1 ROM patcher

You can find the latest ROM-less base UF2 firmwares in the releases tab. Maximum ROM file size is currently 1048576 bytes (1 MB) for the single ROM FW and 524288 bytes per ROM for the "2 in 1" FW.

Building a FW from Scratch

Requirements:

1. Python
2. CMake
3. RP2040 C SDK installed and paths set up

Steps

1. Use the bin2c.py script to convert a ROM file to a C-array. Usage: bin2c.py ROMFILE rom.h. Place the genereated rom.h file in the root of code directory, beside main.c.
2. Run make in the code directory.
3. Connect the RP2040-Zero board to the computer while holding down the BOOT button.
4. Drag and drop the newly generated .uf2 file onto the RP2040-Zero.

Hardware Side

BOM

Reference	Value	Links
U3	RP2040-Zero board (not with pre-soldered pin header)
R1, R2	100 kOhm resistor (0805)	LCSC

Note: I would recommend to get an "authentic" WaveShare RP2040-Zero board and not a clone. Clones may use different parts, e.g., different Flash chips, which could end up not working as the PM2040 is quite pushing the timings of the RP2040, as well as the Flash chip. See here for recommendations for spotting fakes.

PCB

The PCB can be ordered using the Gerber files. A width of 1.0 mm should be chosen with ENIG surface.

Soldering up the RP2040-Zero Board

We do not only make use of the RP2040-Zero board's castellated edges, but also the small contact pads on the back. These pads are rather small, so make sure to align the board correctly, such that the VIAs of the PCB line up with the pads. It can also be helpful to pre-tin the RP2040-Zero's additional pad with a thin layer before actually soldering the pads via the through-holes.

Shell

A 3D printable shell for the cart can be found in the folder "shell".

Disclaimer

Use the files and/or schematics to build your own board at your own risk. This board works fine for me, but it's a simple hobby project, so there is no liability for errors in the schematics and/or board files. Use at your own risk.