cvhviz/CAIRN cairn-v132

Cairn 132

on GitHub

Cairn 132 redraws two of the scanners, fixes emoji taps on the touch keyboard, and makes the touch boards feel smoother when the mesh is busy: flash saves now wait for the screen to go dark instead of stalling it while you watch. It also carries the Heltec V4-R8 (OLED) and Tracker V2 fixes that replaced their Cairn 131 files on November 12. The board list is the same as 131's.

Highlights:

• Wi-Fi scan: each network drawn over the channels it really covers (touch and key boards, and the T-Display SF32's scan page). A network's shape is flat across its channel and drops straight to the floor at the channel's edge, the way Wi-Fi analyzers draw it: a 20 MHz network on channel 2 covers channels 1-4, a 40 MHz one 1-7. Before, the shapes had long sloping sides, so a 40 MHz network on channel 2 seemed to spread over 1-9. The outline now closes down to the floor on both sides, and a 40 MHz network's name on the plot is followed by "40 MHz", so its wider shape explains itself.
• Spectrum › Channel draws like the Band scan (every touch board). The trace is a filled area colored by level over the floor (teal, amber, red), so a packet stands up out of the floor in its strength's color, with the average as a white line over it. The heat map below reads as the Band waterfall: an indigo field with readings glowing purple to yellow, and a column with only a reading or two no longer paints bright yellow. Only the drawing changed; the readings and the app feed are as they were.
• Emoji taps work on the keyboard's emoji panel (touch boards). A finger that drifted a little while pressing (the L2 Pro's panel does this) turned the tap into a scroll, so nothing was typed. Now a press on an emoji types it if the finger lifts on it, and the panel scrolls only once the finger has clearly moved up or down.
• No hint text in an empty message field. The conversation's field no longer shows "Message Bob…" or "Reply to Bob…", and the keyboard's field no longer shows "Message". The reply bar above still says who you're replying to. Name, password, channel and command fields keep their hints.
• Less lag when adverts and messages arrive (ESP32 touch and key boards: L2 Pro, Heltec V4 touch kits, ThinkNode M9, T-Deck, T-LoRa Pager). The screen used to hitch because saves to flash ran while you were looking at it:
  • The chat history, the offline message queue, the contact list and stored adverts now wait while the screen is on (for at most 3 minutes) and save once it goes dark. Power off, restart and update mode still save first.
  • The offline message queue is saved with one write per 2 KB instead of three per message, and not at all when it hasn't changed.
  • A received or sent packet runs at full CPU speed, so an advert's signature check is three times faster.
  • Boards with the mesh in PSRAM hold 32 incoming adverts in memory (was 6), so a burst of adverts never writes to flash while it is being received.

Fixed

• Heltec V4-R8 (OLED) boot loop. After a soft reset the one-button interface could read leftover memory and crash on every start. Fixed, and already in the replaced Cairn 131 files.
• Heltec V4-R8 (OLED) turned itself off on USB with a low battery. The board couldn't tell it was plugged in, so a cell under 3.4 V shut it down about 30 seconds after every start, charger or not. It now powers off only when the cell is low and not rising for 5 minutes. The Tracker V2 got the same fix. Both were already in the replaced Cairn 131 files.
• Emoji taps dropped on the keyboard's emoji panel (see above).

Changed

• Wi-Fi scan and Spectrum › Channel redrawn (see above).
• No hint in an empty message field (see above).
• Flash saves wait for the screen to go dark (see above).
• American spelling on screen: Favorite / Unfavorite, Neighbors, canceled and center, on the T-Display SF32's node pages and admin, the touch calibration, map messages, the advert choice and the Wi-Fi setup alert.
• For testers: a main-loop pass of 150 ms or more while the screen is lit prints an L2SLOW line on the serial console (ESP32 touch and key boards), with each part's time, to find what still makes the screen stall now and then.

Checked: built from one tree for every board, each file checked for the build number and date, its flash layout, and the same set of files as 131. The V4-R8 and Tracker V2 fixes ran on the bench before they replaced the 131 files. Not checked yet on a device: the new Wi-Fi scan and Spectrum drawings, the emoji panel and the saves that wait for a dark screen. The L1 family, the T096, the repeaters and the T-Display SF32 (apart from its Wi-Fi scan page and spelling) get only the new build number.

Update

• On Cairn 108 to 131 (L2 Pro, Heltec V4 touch on either kit, ThinkNode M9, T-Deck, T-Display SF32, T-LoRa Pager): Settings › System › Firmware update: Check, Download, Install. The new build starts on trial and goes back to the old one by itself if it fails to start. On the T-Display SF32, dock the core on the keyboard board first (it carries the Wi-Fi chip).
• T-Deck started from an SD-card launcher: don't use Update on 121 or earlier (122 and later are fine). Copy MeshCore-TDeckPlus-Cairn132-2026-11-12-update.bin to the card and install it from the launcher, as you installed Cairn.
• Over USB on an ESP32 board: the -full.bin goes at 0x0, after Erase Flash, and erases everything. The -update.bin goes at 0x10000 and keeps your data. If the board last updated over Wi-Fi, clear the boot selector first, as in the ESP32 install guide.
• Heltec Wireless Tracker V2 and V4-R8 (OLED) companions: update with the -ble-update.bin at 0x10000; these two don't update over Wi-Fi. A first install is the -ble-full.bin at 0x0 after an erase (back up your node's private key from the app first if the board runs MeshCore or Meshtastic now). Files with -repeater in the name are the repeater, not the companion.
• Wio Tracker L1 Pro, DV1, L1 e-ink, the room server and the T096: double-tap Reset and copy the board's .uf2 onto the drive that appears (UF2 guide), or use the Cairn app's Firmware Update over Bluetooth. Updating keeps your identity, contacts, channels and settings.
• Compact repeaters: write the -repeater-update.bin at 0x10000, or copy the -repeater.uf2. They don't update over Wi-Fi.
• T-LoRa Pager: pick the file for your radio (it's on the box and the back label). SX1262 units take TLoraPager, LR1121 units take TLoraPagerLR1121; the wrong one runs but has no radio. The online update keeps to the radio you installed.
• A board without Cairn: write the board's -full.bin (ESP32 install guide), copy the .uf2 (UF2 guide), or run the SF32 installer (SF32 install guide).

Downloads

The compact repeater files (-repeater in the name) are rebuilt from the same tree: Heltec T096 and T114 (.uf2), and the Heltec Wireless Tracker, Tracker V2, V2, V3, V4 and V4-R8 (-repeater-full.bin and -repeater-update.bin). Cairn 132 runs on MeshCore 1.18.0, as 118 to 131 did. SHA256SUMS.txt covers every file: shasum -a 256 -c SHA256SUMS.txt.

Not in this release: the experimental boards (what experimental builds are). The Heltec T114 companion, the GAT562 30S Mesh Kit companion and the ThinkNode M9 USB companion stay on Cairn 131; the Heltec Vision Master T190 and WiFi LoRa 32 V3 companions stay on Cairn 130, and the LilyGO T5 E-Paper S3 Pro and the SenseCAP MeshPager X2 stay on Cairn 127.