Intel 82562EX, Руководство по конструкции

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82540EP/82541(PI/GI/EI) & 82562EZ(EX) Dual Footprint Design Guide
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2.2 PCI Interface for 82540EP/82541xx Family of Gigabit
Controllers
The 82540EP and 82541xx controllers provide 32-bit interfaces for a 33 MHz or 66 MHz PCI bus
meeting PCI 2.3 Specifications. The PCI 2.3 Specification trace routing instructions should be
followed.
The Ethernet controllers operate as PCI slave devices for configuration and register programming.
After the devices have been properly initialized, they can also operate as PCI masters to fetch
memory descriptors and to read/write data buffers.
The devices are capable of operating in either a 5 V or 3.3 V signaling environment. The VIO
terminals can be connected to either 3.3 V or 5 V to choose the appropriate PCI bus levels. These
connections bias the controller PCI I/O buffers for the correct switching strength. However, all
other digital inputs and outputs use 3.3 V signaling unless specified separately.