
5.2 Logical Interface
5.2.1 Communication layers
Each of the layers is outlined below.
Physical layer
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Detects, sends, and receives band signals.
Sends serial data to and receives it from the link layer.
Link layer
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Negotiates against mutual transfer requests between the host system and device.
Encodes serial data as 10- or
Inserts auxiliary signals (SOF, CRC, and EOF), deletes auxiliary signals, and communicates with the transport and physical layers.
Transport layer
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Exchanges data in communication with the link layer, and builds the frame information structure (FIS).
Contains a (Shadow) Block Register.
Reflects the FIS contents to the Block Register.