Info taken from http://www.trimslice.com/wiki/index.php/Firmware_Update

     Unzip the archive into firmware-updater.img
    Create a firmware SD card using the uncompressed firmware-updater.img file:

   # dd if=firmware-updater-v2012.04-1.02.img of=/dev/sdd bs=1M

    ( http://trimslice.com/download/firmware-updater/v2012.04-1.02/firmware-updater.2012.04-1.02.img.zip )

    Open the micro-SD security door to access the recovery-boot button.
    Insert the firmware SD card into the front SD socket.
    Unscrew the micro-SD door security screw. Open the micro-SD door.
    Power on the Trim-Slice while pressing the recovery-boot button.
    The Trim-Slice will automatically boot and write the new firmware onto the SPI flash.
    When the update process is complete, the Trim-Slice indicator LEDs start to blink.
    Shut down Trim-Slice and remove the firmware SD card.
    Restart Trim-Slice.