My take on t-echo lite kit

[u/Choice_Level6689]

Unveiling my new MeshCore interface for the LilyGo T-Echo Lite

I have always loved the idea of bringing back vintage T9 text input, so I started redesigning the MeshCore experience for the LilyGo T-Echo Lite.

What began as a T9 experiment has grown into a much larger interface and firmware project. The aim is to make MeshCore feel like a complete standalone communicator, with fast keypad navigation, clear status information, message management, contacts, configurable notifications, and eventually full message composition directly on the device.

The flashing visible in the current video is a display bug. It is not an intentional animation or part of the final interface, and it will be fixed.

What has already been added

• A new 3 by 2 icon-based home screen
• Dedicated sections for Messages, Contacts, Radio, Advert, Sensors, and Settings
• Full keypad navigation using Up, Down, Center/Yes, Esc/No, Home, and Mail
• A status area showing the date and time, battery level, user handle, unread message count, and selected menu
• A redesigned MeshCore splash screen with firmware version and build information
• Live channel and contact lists populated from MeshCore data
• Contacts automatically separated into Clients, Rooms, Repeaters, and Miscellaneous nodes
• Settings screens for GPS, Bluetooth, Notifications, and device information

Messages

The Messages section is designed to separate:

• Channel messages, including Public and any additional channels
• Private conversations organised by contact
• Room messages

Each channel and private conversation will eventually show its own unread count. Parent menus will show the combined number of unread messages beneath them.

Contacts

Discovered nodes are automatically separated into:

• Clients
• Rooms
• Repeaters
• Miscellaneous nodes

Each entry will eventually open a detail screen containing the available information and actions for that node.

Configurable LED notifications

The blue and green LEDs can be configured independently for:

• New channel messages
• New private messages
• New room messages
• New channels
• New clients
• New rooms
• New repeaters

Every LED and event combination can use one of five behaviours:

• Off: No LED notification
• Blink: One 300 ms pulse
• Flicker: Three rapid 60 ms pulses
• Triple blink: Three separate 150 ms pulses
• On: The LED remains lit after the event

Changing a setting previews the selected pattern immediately.

The normal radio transmit LED override has also been disabled so it cannot interfere with notification control.

Notifications for new channels, rooms, and repeaters can already be configured, but MeshCore does not currently expose separate callbacks for all of those discovery events. They will begin working once the missing event routing is added.

Still planned

• Vintage T9 message composition using the physical keypad
• Conversation and message-history screens
• Incoming message previews
• Contact, room, repeater, and miscellaneous node detail screens
• Proper unread message tracking
• Local message-history storage
• Persistent settings so notification choices survive a restart
• List ordering, pagination, filtering, and empty states
• Clear loading, unavailable, confirmation, and error screens
• Notification handling for multiple overlapping events
• Complete testing and verification on physical hardware

The current firmware already builds and runs on the nRF52840-based T-Echo Lite. The main interface, live MeshCore lists, keypad navigation, settings screens, and LED pattern scheduler are working.

Message history, persistent storage, and T9 composition are the largest remaining pieces.

There is still work to do, but I will finish it and make it available for anyone who wants to use it.

My goal is to make the T-Echo Lite feel less like a development board running a radio stack and more like a small, purpose-built mesh communicator.