As described, my FRDM-K66F OpenSDA interface only ever starts in bootloader mode, despite the fact that I am not holding down the reset button while plugging it in. Yesterday it was working fine and I was able to debug code through the interface from MCUXpresso.
The green LED DS2 is blinking a couple times a second and the device appears as a drive in Explorer (Windows 10).
This is our second FRDM-K66F; the first one doesn't work now because we tried to upgrade the OpenSDA firmware and the device bricked. A second board was brought in while we wait for a J-link to manually fix the first board.
Any help would be appreciated.