RE: Topologies and attendance
About (1) - so it is something like communication between power supply and power sink - could this communication model (layer 1 at least) be used in UPAMD?
From: upamd@xxxxxxxx [upamd@xxxxxxxx] On Behalf Of Atkinson, Lee [Lee.Atkinson@xxxxxx]
Sent: Friday, September 03, 2010 2:49 AM
To: upamd@xxxxxxxx
Subject: RE: Topologies and attendance
A couple of related usage models;
1. Notebooks with docking stations; the docking is a serial connection (the EPS is connected to dock, and then the dock provides power to the notebook). The docking station has its own power consumption which is variable, uncontrollable and not directly measurable by the notebook.
With HP notebooks, the AC adapter meters the actual output current and signals when the AC adapter is near its output capacity. The message is received by the notebook and the notebook reduces its power consumption.
2. Value in knowing the power source; Under-seat power on an airplane is 15.0vdc, identifying this source is valuable for 2 reasons;
a. HP recommends against charging the notebook on an airplane, and disables charge if we see a voltage that indicates such (as a safety precaution).
b. The power capability of the in-seat power is limited (to 75watts, I think). Unless the airplane is expected to adopt the UPAMD standard, then any adapter that would interface to the in-seat power should identify the source and communicate the capability of the source.
--Lee Atkinson, HP