Interface

5.2 Logical Interface

The host system and the device communicate with each other by sending and receiving serial data.

The host and the device have several dedicated communication layers between them. These layers have different functions, enabling communication between the different levels of layers within the host or device and between layers at the same level that link the host and device.

Figure 5.3 is a conceptual diagram of the communication layers.

Host:

Application

Device:

layer 4

Software control

 

Software control

Buffer Memory

 

Buffer memory

DMA engine(s)

 

DMA engine(s)

Shadow Block Register

Transport

Block Register

layer 3

Transport Layer

 

Transport Layer

 

Link

 

Link Layer

layer 2

Link Layer

 

 

Physical

 

 

layer 1

 

Physical Layer

 

Physical Layer

Host located layers

 

Device located layers

Figure 5.3 Conceptual diagram of communication layers

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Fujitsu MHW2040BS, MHW2100BS, MHW2080BS, MHW2120BS, MHW2060BS Logical Interface, Conceptual diagram of communication layers