Removing RTC from Theft-Deterrence

C. Scott Ananian cscott at
Wed Jul 7 16:57:19 EDT 2010

On Wed, Jul 7, 2010 at 4:48 PM, John Watlington <wad at> wrote:
> On Jul 7, 2010, at 4:01 PM, C. Scott Ananian wrote:
>> Since "RTC security" is being discussed again, I'm going to repost two
>> relevant proposals from "the good old days".  First: on making
>> theft-deterrence a "feature"; then technical details of a $0.16 change
>> to remove RTC dependence from the theft-deterrence feature.
>> Unfortunately, the specific circuit changes required are XO-1
>> specific; presumably some slightly different version is needed for XO
>> 1.5, XO 1.75, etc.  I vaguely remember wad saying he managed to make
>> this change in hardware at some point; I don't know if corresponding
>> software was ever written.
> The EEPROM needed for this was included in early XO-1.5 prototypes,
> but was dropped from production due to the lack of software making use
> of it.   It could be added back to any XO-1.5 SKU for a slight cost increase.

Unfortunately, the software changes required are to EC code, which is
difficult for outside contributors to work on.  (Also some OFW work,
but that's available and easily hackable.)

                         ( )

More information about the Devel mailing list