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RE: Clause 33 comments




Ed,

In discussing clause 33 implementation with a colleague, we realized another
item 
that needs to be clarified in connection with the stored address and
components that
implement multiple devices sharing one MDIO interface.

If each device (using device in the sense of "device address" from clause
33) had
its own MDIO interface, each would have the register address stored
so that multiple reads, writes, and write-increments would operate using the

stored address even if there were intervening operations executed to other
devices.

If devices share an MDIO interface, are they to have a register address
stored
per device or can they have just one register address register shared
between 
all? If the latter is allowed then the manager will need to write an address
any time it changes devices.

If there is only one address register per MDIO interface, what happens if 
an MDIO interface with multiple devices gets accessed for different devices
without an intervening address operation? Should it remember that the
address
was for a different device and not execute the read or write or does it
just use the stored address anyway?

If we don't pin some of these details down, people may get clever and use
undocumented features causing later interoperability problems.

Pat