Re: Topologies and attendance
I think that we should clearly define the 'UPAMD domain' as the output port of an adapter and the input port a one device.
Any other communications that leave or enter that domain should be clearly defined.
This way all of the topologies in Bob's diagrams would be covered with one simple set of rules. Among others, this set of simplifying restriction would be useful:
- A device does not _need_ to know about the power source of an adapter.
- A device does not _need_ to know about the presence of other devices (e.g., in other ports on the adapter).
- An adapter does not _need_ to know about other devices down-stream (e.g., a device getting power off another device).
- A device does not _need_ to know if it lies off a hub or an adapter.
- A device does not _need_ to know about other types of power ports on the adapter.
- An adapter does not _need_ to know that a 'device' is really a cable that connects to a legacy (non-UPAMD) device. (BTW: Bob, this is one of the missing topologies).
Note that all of this falls into one simple rule: "UPAMD only governs the exchanges between one device and one adapter" with a very clear definition of the needed exceptions to this rule (e.g., cable-level indicators or interfaces, subset of UPS messages, subset of smart grid messages, and device-software initiated requests).
The only clear exception I see to this view of the 'UPAMD domain' would be from the point of view of certification. This will require special rules for a multi-port adapter or device. E.g., "it is UPAMD-compliant if every single UPAMD-port on the device can be individually certified, with all ports loaded to capacity."
Edgar
On Sep 1, 2010, at 3:18 PM, Piotr Karocki wrote:
> Oh, some very interesting options...
>
> a) USB power ports on UPAMD adapter - sounds good to me , but it may be made as "normal" UPAMD port, and special cable-converter (with built-in logic to communicate with UPAMD adapter, to send messages as "please set 5 V, with limit xx, for as long as you can")
>
> b) such cable-converter could be also made e.g. for my tablet - built-in logic should only send other parameters to UPAMD adapter. Maybe some company would manufacture cable-converters with some method of manually setting parameters as voltage and amperage :)
>
> c) and most important, what you drew on "expansion box" - more than one concurrent power input. How would such possibility add to cost of adapter/expansion box?
>
> I think we should vote about "more than one concurrent power input" configuration - allow or disallow (support or not support) such configuration.
>
> d) also "expansion box", UPAMD device after UPAMD device. It suggest that "expansion box" should steer UPAMD adapter after any plugged-in (to expansion box) device change parameters. It requires more work on communication protocol.
>
> I think this is another topic for vote - existence of 'active expansion box', i.e. not simply split power from one socket to more sockets, but also for e.g. voltage conversion in it.
>
>
>
>
> From: upamd@xxxxxxxx [upamd@xxxxxxxx] On Behalf Of Bob Davis [bobd@xxxxxxxx]
> Sent: Wednesday, September 01, 2010 8:06 PM
> To: 'UPAMD'
> Subject: Topologies and attendance
>
>
> UPAMD,
>
> Attached is the topology drawing I promised to send out to stimulate ideas on the things the UPAMD power distribution system can accomplish. These are just potential thoughts. Feel free to expand and share.
>
> I did not realize that Austin was not on the call and I failed to capture the attendance. If you were in attendance please send me a quick email to that effect.
>
>
> Respectfully;
>
> Bob Davis
> UPAMD Chair
> bobd@xxxxxxxx
> 408.857.1273