[ML-General] If your device just broke in the last few days it might be FTDI sabotage

[Hunter Fuller]

The bad driver was pulled by Microsoft and ftdi has removed the "feature"
in new versions.
On Oct 24, 2014 1:00 PM, "Arthur" <Arthur at cd-net.net> wrote:

>
> https://www.techdirt.com/articles/20141023/15502828928/microsoft-windows-update-completely-kill-devices-that-might-possibly-be-used-piracy.shtml
>
> It looks like FTDI is deliberately bricking chips!
>
> You can fix it, but you need an FTDI flash program, and need to know the
> original chip PID.
>
> Quote from an AC that seems to know what's going on:
>
> There's no doubt they did it on purpose. Someone reverse-engineered the
> bricking routine from the driver. It*unconditionally* writes 0 to the PID
> and a matching value to the checksum, but does so in a specific way that
> fails to write on genuine parts*.
>
> There's no legitimate purpose for the bricking routine. It's a
> no-operation on genuine parts. It's not "something useful the driver does
> which happens to do the wrong thing on non-genuine parts". The only
> possible explanation for the existence of that routine is to zero the PID
> on counterfeit or compatible parts**.
>
> * From what I could understand, the genuine parts can only write to the
> EEPROM in 32-bit units, sent as a pair of 16-bit units. The bricking code
> sent only one of the 16-bit units, so the write never happened. The
> compatible parts write each 16-bit unit as it's received, so the write
> happened.
>
> ** My guess as to why they only erased the PID, and not the VID: due to
> word alignment, if they erased the VID it would happen even on genuine
> parts. Luckly, this makes it easier to recover: if the VID is FTDI and the
> PID is zero, it's a part which used to have a PID of 6001 but was bricked.
> The Linux driver has been patched to recognize a bricked part as a valid
> FTDI part.
>
> Sincerely,
> Arthur Moore
> (256) 277-1001
>
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