Enumerable I2C busses

M. Warner Losh imp at bsdimp.com
Fri Nov 28 20:41:59 PST 2008

In message: <86od054iaz.fsf at ds4.des.no>
            Dag-Erling_Smørgrav <des at des.no> writes:
: Rafał Jaworowski <raj at semihalf.com> writes:
: > Well, hard-coded addresses and conflicting assignments between vendors
: > do not technically prevent from scanning the bus; actually, our
: > current iicbus code can do bus scaning when compiled with a diag
: > define.
: I haven't looked at how that is implemented, but - I2C version 3
: describes device enumeration and identification, but AFAIK very few
: devices actually support it.
: This is really stupid, BTW.  Philips could easily have required the
: first few bytes of the device address space to contain a vendor / device
: ID, along the lines of PCI and USB, from the start.  I wonder: did it
: not occur to them, or did they intentionally leave it out to save a few
: microcents per chip?

EEPROMs typically don't have registers at all.  They are just memory.
Forcing them to have set content would break all kinds of


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