The lab for your Chameleon

01 / YOUR WORKSPACE

Everything your device can do
In one place

One app for Windows, macOS, Linux, Android and the browser. USB on desktop and in the browser, Bluetooth on phones, TCP everywhere.

The web version needs Chrome or Edge on a desktop: Firefox and Safari do not support Web Serial.

02 / THE DIFFERENCE

Why ChameLab

How the app compares with the Flutter ChameleonUltraGUI and the command line client.

• One codebase, five targets. Windows, macOS, Linux, Android and WebAssembly share the same views and protocol code, so a fix lands everywhere at once.
• The firmware moves with the app. Features like slot colors are added on both sides together and shipped in the same release.
• Adaptive layout. Side navigation on a desktop, a drawer on a phone, and the keyboard and system Back button handled properly on Android.
• Cards first. Read a card, save it to the library, put it into any slot, and the slot shows which saved card it holds, matched by UID.
• The CLI is the app's code too. The command line client is written in C# on the same protocol and key recovery code as the app, and comes as a single program for Windows, macOS and Linux, with no Python to install.

Still on the roadmap: QR sharing.

03 / UNDER THE HOOD

The firmware

The ChameLab firmware runs on both ChameleonUltra and ChameleonLite. Here is what is new in it.

Multi-card LF New Only here

An LF slot can hold up to eight cards of any emulated LF type (EM410x, Electra, HID Prox, ioProx, Viking, PAC, Jablotron, IDTECK, Pyramid), mixed in any order. Each time the reader's field appears the slot sends the next card in the list, one steady card per tap, wrapping back to the first — so you tap until the right card opens. Neither the stock firmware nor any other app or firmware for the Chameleon can do this.

• One card per tap: a single steady card per field appearance is the cleanest transition for access readers, and there is no per-card timing to tune.
• Position kept across sleep: the next card is remembered between taps; a battery pull or switching slots restarts at the first card.
• Kept with the slot: the list survives restarts and follows the slot when slots are swapped. Single-card slots work as before.

Build the list in the ChameLab slot editor from your saved cards and drag to reorder. Apps use the commands 5907–5909; the details are in LF card cycling.

Slot LED colors

Each card in a slot can have its own LED color, so you can tell which card is active by looking at the device. The RGB lines are driven by PWM, so any color works, not only the seven primary mixes. A slot that holds both an HF and an LF card alternates between their two colors. Slots without a color keep the familiar HF / LF colors.

Pick a color in the ChameLab slot editor, or from the CLI: hw slot color -s 3 --hf -c FF5722, --default goes back to the standard color. Apps use the new DATA_CMD_SET_SLOT_COLOR (1900) and DATA_CMD_GET_ALL_SLOT_COLORS (1901) commands.

Earlier fixes

• No more full flash after slot switching Fix: flash records stayed open after reading, so they could never be garbage-collected. After enough slot switches, saving failed until a reboot.

Updating the firmware

The ChameLab app on desktop, Android and iOS updates the firmware for you: it offers the newest release for your device and flashes it over USB or Bluetooth. To flash by hand:

1. Download ultra-dfu-app-<version>.zip or lite-dfu-app-<version>.zip from the release below. The -full packages also contain the bootloader and are only needed for recovery.
2. Put the device into DFU mode: hw dfu in the CLI, or hold button B while plugging in USB.
3. Flash the package with firmware/flash-dfu-app.sh, nRF Connect for mobile or nRF Connect for Desktop.

Slots, cards and settings are kept by an application update. See the full changelog.