Note: If you have purchased our Wi-Fi Connection Service, we already know your Wi-Fi name (SSID) and network key (Wi-Fi password), and your new CTC modules will be preconfigured accordingly. You do not need to connect them manually and can proceed directly to “Chapter 4 – Configuring Modules”. The Wi-Fi Connection Service is included with all CTC Starter Sets and CTC Routers.

There are two ways to connect modules to Wi-Fi:

  • The first method will likely be familiar from other Wi-Fi-enabled products: You connect to the CTC module’s configuration Wi-Fi and enter your Wi-Fi details in a browser form.
  • The second method is much more convenient via the CTC app, but it often fails on Windows due to the stubborn operating system.

Notes:

  • Until firmware version 20230329, the length of passwords and SSIDs was limited to 20 characters. Newer firmware complies with the Wi-Fi standard: SSID (32 characters), Wi-Fi password (63 characters).
  • The CTC modules indicate their status via LED blink codes or front light signals—see Chapter 3.3 “Module Status Indicators”.

Registering with the CTC App

Notes:

  • On iOS (iPhone/iPad), this function is unfortunately not available, as Apple does not provide a suitable API for this purpose.
  • On Android, the global “Location” function must be enabled, just as it is required for navigation apps. Depending on the manufacturer and Android version, the update of detected Wi-Fi networks can be very slow—this is intended to save battery.

The CTC app can detect modules in configuration mode at the press of a button and write the Wi-Fi configuration to the CTC module. After writing the Wi-Fi configuration, the CTC module automatically resets and then connects to the model railway Wi-Fi.

A CTC module switches to configuration mode when:

  • it is a new CTC module (without Wi-Fi configuration).
  • it is already configured but cannot find its Wi-Fi. In this case, it switches to configuration mode after one minute, waits two minutes for a connection, and then resets automatically.

You can recognise that a CTC module is in configuration mode by its status indicator (LED or headlight) glowing continuously.

Via the menu Settings/Search New Modules, the app searches for available Wi-Fi networks:

ctc-app-doku-bild

To register, enter the SSID and password of your model railway Wi-Fi, and ideally also a name for the module. Then select the module and click Register Module.

ctc-app-doku-bild

During this process, your PC/tablet/smartphone connects to the CTC module’s configuration Wi-Fi and writes the configuration file netCfg.xml to the CTC module. As with all configuration changes, the CTC module resets automatically and will then be visible in your model railway Wi-Fi.

Notes:

  • Especially on Windows 10, issues may arise when activating the correct Wi-Fi. If the CTC app displays the message “I/O error during upload”, clicking the Register Module button a second time usually helps. If that doesn’t work, you can manually connect to the module’s configuration Wi-Fi via Windows’ Wi-Fi management before clicking Register Module.
  • If the PC does not have a wired connection to the model railway network during registration, it will lose its connection to the model railway network. Sometimes, you may need to manually reconnect it to the model railway Wi-Fi afterward.

Logging In via the CTC Module’s Website

Note: This feature is only available starting with firmware version 20210220, which is included with CTC-App v3.05 and pre-installed on all CTC modules shipped after 21.02.2021.

A CTC module in configuration mode will appear in the list of available Wi-Fi networks on your PC, tablet, or smartphone. You can identify the configuration Wi-Fi networks of your CTC modules by the letter-number combination (MAC address in hex code) at the beginning. Here is an example from Kubuntu Linux: ctc-app-doku-bild


  1. Connect your PC, tablet, or smartphone to this configuration Wi-Fi.
  2. Open your web browser and enter the address http://192.168.4.1. ctc-app-doku-bild
  3. Click the link “Edit WiFi SSID and password”. Enter the SSID (Wi-Fi name, network identifier) and password (network key) of your model railway Wi-Fi. ctc-app-doku-bild
  4. Click “Save”. ctc-app-doku-bild
  5. The CTC module will restart automatically and should now appear in your model railway Wi-Fi.

Note: The module remains in configuration mode for only about 2 minutes before restarting. If the module has a Wi-Fi configuration but cannot connect to that Wi-Fi, it will switch back to configuration mode after about 1 minute. If you mistyped the SSID or password, you must wait one minute before you can access the module again via its configuration Wi-Fi.

Note: You can determine whether the CTC module is in configuration mode by checking the status display of the CTC module.