Fujitsu MHT2080BH Manuale Utente

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Interface 
 
5-10 C141-E203-01EN 
5.2.1 Communication layers 
Each of the layers is outlined below. 
Physical layer 
• 
Detects, sends, and receives band signals. 
• 
Sends serial data to and receives it from the link layer. 
Link layer 
• 
Negotiates against mutual transfer requests between the host system and 
device. 
• 
Encodes serial data as 10- or 8-bit data, then converts it into DWORD data. 
• 
Inserts auxiliary signals (SOF, CRC, and EOF), deletes auxiliary signals, and 
communicates with the transport and physical layers. 
Transport layer 
• 
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.