Fdl2 Failed -

"FDL2 failed" is never a problem with your code. It is always a problem with the hardware stack below it. Treat it as a physical layer issue, not a software bug. Check your cables, check your drivers, and for the love of debugging, buy an FTDI cable with a ferrite bead.

: In some instances, if the image being flashed is too large or the process takes too long, a hardware watchdog may trigger a reboot, causing the connection to drop exactly when FDL2 is meant to take control. fdl2 failed

Because the error log doesn't specify if the failure is due to a "timeout," "authentication error," or "partition write failure," I was left scouring obscure developer forums for hours. "FDL2 failed" is never a problem with your code