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peng-zhihui/l-ink_card

7,617CAudience · developerComplexity · 5/5DormantSetup · hard

TLDR

A DIY smart card project that combines NFC with an e-ink display and a dial to switch between multiple stored card identities in one physical device.

Mindmap

mindmap
  root((L-ink Card))
    What it does
      Store multiple card identities
      Switch via physical dial
      Display active card on screen
    Hardware
      STM32L051 microcontroller
      ST25DV NFC chip
      E-ink display 200x200
    Included files
      Circuit diagrams and PCB
      Firmware source code
      3D printable case
    Companion App
      Android app
      Customize screen info
      Manage stored cards
    Audience
      Hardware makers
      Embedded engineers
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Code map

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Things people build with this

USE CASE 1

Build a single card that physically switches between your office access card and gym membership card using a dial.

USE CASE 2

Prototype a custom NFC-enabled wearable that shows dynamic status information on an e-ink screen.

USE CASE 3

Learn embedded firmware development with STM32 microcontrollers and e-ink display drivers.

USE CASE 4

Create a low-power smart badge that displays your contact info and can share it wirelessly via NFC.

Tech stack

CSTM32NFCAndroidPCB design

Getting it running

Difficulty · hard Time to first run · 1day+

Requires ordering custom PCBs, soldering SMD components, flashing STM32 firmware, and building or sideloading the Android app.

No explicit license information provided in the explanation, terms unclear.

Copy-paste prompts

Prompt 1
I want to build the L-ink card project. Walk me through flashing the STM32L051 firmware and pairing it with the Android companion app.
Prompt 2
Show me how to modify the L-ink card firmware to display a QR code on the e-ink screen instead of plain text.
Prompt 3
Explain how the L-ink card uses a physical dial to switch between embedded NFC chips rather than software emulation.
Prompt 4
Help me design a PCB similar to L-ink card that uses an STM32 microcontroller and an ST25DV NFC chip.
Prompt 5
What are the steps to send the L-ink card KiCad PCB files to a PCB manufacturer like JLCPCB?
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