Logical Interface; Figure 5.3 Conceptual Diagram Of Communication Layers - Fujitsu MHW2120BK Maintenance Manual

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:
Software control
Buffer Memory
DMA engine(s)
Shadow Block Register
Transport Layer
Link Layer
Physical Layer
Host located layers

Figure 5.3 Conceptual diagram of communication layers

C141-E261
Application
Device:
layer 4
Software control
Buffer memory
DMA engine(s)
Transport
Block Register
layer 3
Transport Layer
Link
layer 2
Link Layer
Physical
layer 1
Physical Layer
Device located layers
5.2 Logical Interface
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