GreyCTF Summit 2025 · Singapore · 2025

GreyCTF Summit 2025 GreyBadge

Singapore RP2350 and ECP5 FPGA challenge badge

NUS Greyhats' public GreyBadge archive identifies the 2025 GreyCTF badge as GreyMecha/Army, with RP2350-side CircuitPython firmware, KiCad hardware files, an ECP5U_25 FPGA schematic, GC9A01 SPI display, Li-ion power-path circuitry, summit UF2/filesystem releases, and named challenge apps.

GreyCTF GreyCTF Summit NUS Greyhats Singapore GreyBadge GreyMecha Army RP2350 CircuitPython ECP5 FPGA GC9A01 PMOD CTF Southeast Asia Asia

EventGreyCTF Summit 2025

SeriesGreyCTF Summit

LocationNUS School of Computing, COM1 Level 2, Singapore

CountrySingapore

People

Authors & Credits

Asteroids app contributor

khian

Filesystem README credits khian for Asteroids.

Source

Bad Apple contributor and technical adviser

sayomaki

Filesystem README credits sayomaki for Bad Apple and also lists sayomaki among people who helped with technical advice.

Source

Bricked Up challenge contributor

Fieash

Filesystem README credits Fieash for the Bricked Up challenge.

Source

GreyHats badge initiator

caprinux

Filesystem README thanks caprinux for initiating the GreyHats badge effort.

Source

RP2350, LiPo, power, challenge, and firmware contributor

itsme-zeix

Filesystem README credits itsme-zeix for PCB work around RP2350, LiPo, and power, plus Leaky Pin and firmware work.

Source

artwork and animations

shuqing

Repository structure and filesystem README credit shuqing for badge artwork and animations.

Source

event organizer and repository owner

NUS Greyhats

Official summit publisher and GitHub organization hosting the public GreyBadge repository.

Source

main badge system designer

Hackin7

Filesystem README credits Hackin7 for main badge system design, concept, artwork and animations, PCB power/FPGA/connectivity work, and firmware.

Source

mirrortune contributor

Codekrodile

Filesystem README credits Codekrodile for mirrortune.

Source

zip-file contributor

sunshinefactory

Filesystem README credits sunshinefactory for zip file work.

Source

Why It Mattered

It adds a current Singapore Greyhats lineage after X-CTF, showing a more ambitious local badge with an RP2350 application processor, FPGA challenge surface, public production files, and summit/finals release trail while keeping image and license limits explicit.

Hardware

The repository README points to hardware artwork, KiCad files, JLCPCB production files, a Prototype 3 order release, and a hardware ordering guide. The schematic trail includes RP2350 sheets, an ECP5U_25 CABGA256 FPGA sheet, a GC9A01 IPS SPI display, USB-friendly Li-ion battery charger and power-path management, D-pad, buzzer, PMOD expansion, FPGA programming, and RP2350-FPGA interlink notes.

Software & Apps

The README setup flow flashes `circuitpython_frozen_leaky.uf2`, mounts the badge as CIRCUITPYTHON, and copies the `firmware/rp2350/filesystem` contents. The filesystem README says the RP-side firmware is based on CircuitPython and includes GreyCTF finals challenges such as Hornet Revenge, Leaky Pin, Bricked Up, Shooting Flags, Secure Memory, and CatCore, while the ECP5 directory keeps FPGA projects and tests with yosys, nextpnr-ecp5, fpga-trellis, and openFPGALoader tooling notes.

Lore

The badge used the GreyMecha/Army theme and a mix of finals and summit release assets. The firmware README credits Hackin7 for concept, artwork, PCB, and firmware; itsme-zeix for RP2350, LiPo, power, Leaky Pin, and firmware work; shuqing for artwork and animations; and additional contributors for challenges, apps, and initiating the GreyHats badge effort.

Lifecycle

Add-ons & Upgrades

FPGA subsystem source-backed

ECP5U_25 FPGA challenge surface

The hardware tree includes an ECP5U_25 CABGA256 schematic and the firmware tree includes ECP5 projects, tests, and a UART coprocessor example with open FPGA tooling notes.