Firmware Update for Retio

This page will guide you through the Retio firmware update process.

  • Last Update: 3/23/2026 (Bug fix)
  • This update is for RETIO ONLY.
  • For Retio Lite Firmware Update, please click here.

    • Web Browser Compatibility

  • If you see a message like this in step 4 below, the web browser you are using is NOT supported.
    This browser "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.1 Safari/605.1.15" does not support Web Serial API yet.
  • This page uses Web Serial API, and ONLY works with Google Chrome or Microsoft Edge as of now!
  • This page was tested on Microsoft Windows, MacOS, and Linux. It should also work on other non-mobile OS platforms with full desktop versions of Google Chrome or Microsoft Edge.

    • Retio Firmware Update Procedure

    Please follow closely in order. Do not skip steps.

    1. Turn OFF Retio using the power switch on the back.
    2. (Optional) Select the firmware version you'd like to use in the dropdown menu below. By default, it is the latest version if you don't choose.
    3. Click the Flash button below, and a dialog will pop up, asking you "support.retio.co wants to connect to a serial port".
    5. While watching the popup dialog, connect your Retio to your computer with a USB-C cable. You should see a new port appeared in the popup dialog.
    6. Select that serial port corresponding to your Retio. Then click Connect.
      Retio front
    7. Under the Flash button in Step 4, it will show "Waiting for Retio. Please turn on the power to continue...".
    8. Flip up the power switch on the back of Retio to start the update process.
    9. The update process will take about 1 minute.
    10. Once it's done, you'll be greeted with "Congratulations! Flashing was successfully complete! ..."
    11. Please remove the USB cable from Retio first.
    12. Power cycle your Retio (turn off, then turn on).
    13. Now the update process is complete.
  • Under rare circumstances, Retio may behave not as expected. For example, it might play radio in non-radio modes.
  • If so, please repeat the update process.
  • The update process was designed so that Retio will not get "bricked". If for any reason the process is interrupted, you may simply restart from the beginning.

    • Check Current Firmware Version of your Retio (Method 1)

  • Change MODE to AUX
  • Single-press VOLUME to see the firmware version on the tube display.
  • For example: 101 means version 1.0.1
  • If the tube doesn't show anything, it means your firmware is the default v1.0.0.

    • Check Firmware Version through Serial Port (Method 2)

    When connected to a computer with a USB Type C cable, the serial port of Retio/Reito Lite is accessible using the configuration below. And the current firmware version number will be displayed in the serial message.

  • Port name: usbserial-1410 or similar
  • Baud rate: 115200
  • Data Bits: 8
  • Parity: none
  • Stop bits: 1
  • Flow Control: none

    • Retio front

    Release Notes

    Retio Firmware Version: 1.0.2

    Release Date: May 26, 2022

    Added Features

  • In CLOCK mode, press-and-hold TUNE will disable the touch pad, and nixie tubes read "01 0".
  • Press-and-hold TUNE again will enable the touch pad, and nixie tubes read "01 1".
  • This works ONLY in CLOCK mode.

    • Retio Firmware Version: 1.0.1

    Release Date: May 6, 2022

    Added Features

  • Display firmware version number when VOLUME is pressed in AUX mode.
  • Nixie tubes will be toggled on/off in radio modes when VOLUME is pressed.

    • Retio Firmware Version: 1.0.0

    Release Date: Dec 25, 2021

  • Factory default.

    • Acknowledgement

    The flash feature on this page is powered by stc.ninja.