Fujitsu MHW2160BJ 用户手册

下载
页码 320
 
5.2  Logical 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: 
Software control 
Buffer Memory 
DMA engine(s) 
Host located layers
Physical Layer  
Link Layer 
 
Transport Layer 
Device located layers 
 Physical Layer 
Link Layer 
Transport Layer 
Device:
Software control 
Buffer memory 
DMA engine(s) 
Application
layer 4 
Transport
layer 3 
Link
layer 2 
Physical
layer 1 
Shadow Block Register
Block Register 
 
Figure 5.3  Conceptual diagram of communication layers 
 
C141-E259 
5-11