// the find
peng-zhihui/L-ink_Card
Smart NFC & ink-Display Card
A DIY NFC card with an e-ink display, built on an STM32L051 and an ST25DV RFID/NFC transceiver, from peng-zhihui (a well-known Chinese maker). It's aimed at hobbyists who want to build their own smart card that displays custom content and want a full hardware+firmware+enclosure+app reference to fork from, not a maintained library to depend on.
Ships everything you need to actually build the thing: Altium schematics/PCB, gerbers ready to send to a fab, a BOM, STEP/STL files for the enclosure, and both CLion and Keil firmware projects. The README is upfront about a real hardware limitation instead of glossing over it — the ST25DV only speaks ISO 15693, not the ISO 14443 protocol most access cards use, so it can't do software-level card emulation, and the author explains exactly why and what chip he'd swap in to fix it. Also bundles a DAP-Link debugger design so you don't need to already own a J-Link/ST-Link.
Dead since January 2021 — no firmware updates, no color-screen revision that was promised, no ISO14443 emulation redesign that was flagged as needed. Documentation is Chinese-only with no translation, which will block a lot of the audience this would otherwise appeal to. The IC-card 'emulation' is a hack: multiple cheap UID chips sharing one antenna, switched by a physical rotary selector, so it scales linearly in components and buttons rather than actually emulating protocols in software. No CI, no license file evident in the tree, and the Android app is described by the author himself as unfinished/unrestyled with no sample project for the reusable module yet.