Configuration
=============

After flashing, the ATM needs to be paired with a funding source — an
`LNbits <https://lnbits.com/>`_ wallet with the **FOSSA** extension. This is what
lets the device generate valid LNURL-withdraw codes completely offline (see
:doc:`introduction`).

1. Create the LNbits FOSSA connection
-------------------------------------

Create an `LNbits <https://lnbits.com/>`_ wallet. Add the **FOSSA** extension and
create a new ATM connection in the extension by clicking **NEW FOSSA**.

.. figure:: assets/wallet-config/wallet_settings_01.png
   :width: 90%
   :alt: Creating a new FOSSA connection in LNbits

   Creating a new FOSSA connection in the LNbits extension.

2. Enter the connection string on the device
--------------------------------------------

Copy the FOSSA connection string. The ATM stores its configuration in flash
memory; on first boot it starts a WiFi access point where you enter that string.

- Connect to the ``LightningATM`` WiFi network.
- Open `http://atm.local <http://atm.local>`_ in your browser.
- Paste the FOSSA connection string and save.

.. figure:: assets/wallet-config/wallet_settings_02.png
   :width: 90%
   :alt: The WiFi configuration portal

   The on-device WiFi configuration portal.

.. tip::

   To reconfigure the ATM later, hold the **BOOT button (GPIO 0)** on the ESP32
   during power-on. The device will re-enter the WiFi configuration portal. The
   BOOT button is on the ESP32 board inside the enclosure and is not accessible to
   end users.

Optional: BlockClock idle display
---------------------------------

The firmware can show Bitcoin network data (block height, price, fees,
difficulty, mempool stats) on the e-paper display while the ATM is idle — the
"BlockClock" mode, fetched in the background from mempool.space. This requires a
WiFi network with internet access and is configured in the same portal. It is
purely a display feature and does not affect offline withdrawals.