This release fixes problems in the firmware concerning USB device detection on some flavors of Windows. Previous firmware versions disabled the USB interrupt for short amounts of time during rendering. This had no adverse effects on Linux and also worked reliably on Windows 7, although it is not quite conforming to the USB spec.

On Windows versions 8.1 and later, this problem causes the device detection for the Overlay64 USB device to only work sporadically.

If you have an external programming device, use it to upgrade to this firmware version by flashing the combined firmware image to the Atmel.

If you don’t have an external programming device and device detection does not work reliably on your system, temporarily remove the LM1881 IC as a workaround. Without the LM1881 no text will be displayed, but the USB device(s) should be properly detected under Windows 8 so that you can use the regular update procedure:

overlay64 update overlay64-firmware-1.2.hex

Changes in the software include fixes for building on MacOSX and fixes to the configuration file parser.

A detailed list of changes can be found in the remainder of this post.

As always, please refer to the project page for detailed documentation.

Changelog for version 1.2


  • USB interrupts are no longer temporarily disabled during display (reported by Richard van der Wolf)
  • Fixed a bug in manual bootloader entry
  • Fixed a parser bug misinterpreting lines containing equal signs as symbol definitions (reported by Sven Arke)
  • Fixed build/configure errors on MacOSX (reported by Rene Stopper)
  • Added bash completion support


  • No changes have been made to the hardware in this release