UniPro protocol stack: Difference between revisions

Revision as of 06:09, 7 October 2009

Revision as of 06:13, 7 October 2009

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==PHY Adapter Layer (L1.5)==

The main user-level feature provided by L1.5 is to allow the bandwidth of a UniPro bandwidthlink to be scaledincreased by using multiple2, PHY3 or 4 lanes. Thiswhere increasesneeded instead of just one. To the bandwidthuser upsuch toa multi-lane link simply looks like a 2x, 3x, or 4x faster fourphysical timeslayer. Applications that mainly require bandwidth in one direction but require modest bandwidth in the opposite direction, can have multiple lanes in one direction and a single lane in the other direction.

Architecturally, the PHY Adapter layer also serves to hide the differences between the alternative PHY technologies (D- and M-PHY). This abstraction thus mainly gives architectural flexibility. Abstracted PHY details include the various power states and employed symbol encoding schemes.