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3 operation, 1 initialization, 2 buffer structure for ethernet controller block – NEC Network Controller uPD98502 User Manual

Page 300

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CHAPTER 5 ETHERNET CONTROLLER

300

Preliminary User’s Manual S15543EJ1V0UM

5.3 Operation

5.3.1 Initialization

After a power on reset or a software reset, V

R

4120A has to set the following registers:

i)

Interrupt Mask Registers

ii) Configuration Registers

iii) MII Management Registers

iv) Pool/Buffer Descriptor Registers

5.3.2 Buffer structure for Ethernet Controller block

The data buffer structure for Ethernet Controller is shown in Figure 5-4.

Figure 5-4. Buffer Structure for Ethernet Block

Buffer Descriptor

Buffer Descriptor

Buffer Descriptor

Link Pointer

Data Buffer

Data Buffer

Data Buffer

Buffer Descriptor

Buffer Descriptor

Buffer Descriptor

Link Pointer (null)

Data Buffer

Data Buffer

Data Buffer