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Downloads

Downloads

Firmware for the OCU-1 handset and its keypad, firmware for the Throttle Bridge, release notes and the printable quick-start card.

OCU-1 handheld throttle

OCU-1 firmware v1.113
XIAO ESP32-C5 · .bin · WiThrottle, Z21 and LCC · flash over USB-C · link to follow
Download
LCC train node simulator
lcc_train_sim.py · a pretend LCC train for testing without a command station · Python 3 · link to follow
Download
Firmware release notes
Every change, by version · HTML
Read
Qwiic keypad firmware 2.x
Reports key releases to the handset · for the SparkFun keypad · link to follow
Download
Quick-start card
2 pp · PDF · printable · to follow
Download
User guide
The full guide, on this site
Read

Throttle Bridge

Throttle Bridge firmware 2.5.3
Lolin D32 · Arduino sketch folder · Z21, WiThrottle, LCC and MQTT in; LocoNet, DCC-EX, XpressNet, LCC and MQTT out · link to follow
Download
Throttle Bridge firmware 2.5.3 (OTA binary)
ThrottleBridge_2.5.3.ino.bin · upload from the setup page on an existing unit · link to follow
Download
Throttle Bridge release notes
Every change, by version · HTML · link to follow
Read
Throttle Bridge guide
Build, set up and use, on this site
Read

Updating the firmware

The handset is flashed over USB-C with the standard ESP32 tools; there is no over-the-air update and no account.

  1. Download the .bin above.
  2. Connect the handset to a computer with the USB-C cable.
  3. Write the image with esptool (or the Arduino IDE / Espressif flash tool) to the XIAO ESP32-C5 at the usual application offset. Exact command lines will be published alongside the first production firmware.
  4. Power-cycle the handset. Your networks, servers, PINs and settings are kept.

If a flash fails, the ROM bootloader is untouched — hold BOOT on the module while plugging in and flash again.

Version policy

Firmware versions are major.minor.patch. Patch releases fix defects and never change behaviour you rely on. Minor releases add capability. We have never removed a feature in a minor release and do not intend to start.

Built on

The OCU-1 firmware is a fork of the open-source WiTcontroller project, using the U8g2, WiThrottleProtocol and Adafruit seesaw libraries. Thanks to their authors.

Updating the Throttle Bridge

The bridge updates itself from its setup page: System → Firmware, choose the .ino.bin, and it flashes, verifies and restarts with your settings, roster and PIN intact. The first flash of a new board is over USB from the Arduino IDE with the Minimal SPIFFS (1.9 MB APP with OTA) partition scheme; after that the page does the rest. The guide has the details.