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Electronic Theatre Controls Inc

My fos/4 Software Update Failed


Trying to Update your fos/4 fixture either via USB or Updaterator, and the UI just cycles or get stuck searching for the file. 

Description/Explanation of Issue

This is possibly an internal bootloader issue. 


  1. Retrieve the firmware file from UpdaterAtor
  2. Rename it as "bundle.bun"
  3. Place the firmware file on the root directory (not inside any folders) of your USB drive.
  4. Insert your USB into the fixture's USB port and power on the fixture while holding the ‘Mode’ and ‘Menu’ buttons.

The fixture will then default and load the bundle from the root of the USB stick.

Once loaded and running, the fixture may have a bundle error present. To fix this, run the upgrade again using the menu option.

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