node-red-contrib-acr122u

A simple Node-RED node for working with ACR122U NFC readers using the nfc-pcsc library.

📦 Installation

Before installing, you should have connected the reader at least once to the computer.
Install via the Node-RED palette manager or with npm in your Node-RED user directory (usually ~/.node-red):

``bash
npm install node-red-contrib-acr122u
`
⚠️ This node depends on the nfc-pcsc library. It will be installed automatically as a dependency.

if not use:
`bash
npm install nfc-pcsc
`
🖧 Requirements
ACR122U or compatible NFC reader

PC/SC smart card service running (usually enabled by default on Windows/macOS)

📚 Usage
This node listens for NFC tags placed on the ACR122U reader and outputs the tag's UID and other relevant info.

Output Message (msg)
Card UID: 2467430b
Card removed: {
atr: ,
standard: 'TAG_ISO_14443_3',
type: 'TAG_ISO_14443_3',
uid: '2677460b'

}
Example Flow
You can wire this node into a debug node or a function node to handle tag scans:


[acr122u] → [function] → [debug]
⚙️ Configuration
This node requires no configuration — just drop it in your flow and it starts listening for cards.

💡 Notes
Only one NFC reader is supported at a time.

Multiple scans may be emitted depending on tag polling behavior.

On Linux, you may need to add your user to the pcscd or plugdev group and ensure the pcscd daemon is running.

🧪 Development
To test your custom node locally:

`bash

cd ~/.node-red
npm install /path/to/your/node-red-contrib-acr122u_nfc
``
Then restart Node-RED.

📝 License
MIT

© 2025 Itu developments. Contributions welcome!



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