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©
Copyright 2004 Cirrus Logic, Inc.
DS651UM21
Version 2.1
CobraNet Hardware User’s Manual
Hardware
3.0 Hardware
shows a high-level view of the CobraNet CM-2 interface hardware architecture.
Figure 2. CobraNet Interface Hardware Block Diagram
Flash memory holds the CobraNet firmware and management interface variable settings.
The CS181xx is the heart of the CobraNet interface. It implements the network protocol
stacks and performs the synchronous-to-isochronous and isochronous-to-synchronous
conversions. The CS181xx has a role in sample clock regeneration and performs all
interactions with the host system.
The sample clock is generated by a voltage-controlled crystal oscillator (VCXO)
controlled by the CS181xx. The VCXO frequency is carefully adjusted to achieve lock with
the network clock.
The Ethernet controller is a standard interface chip that implements the 100-Mbit Fast
Ethernet standard. As per Ethernet requirements the interface is transformer isolated.
VCXO
Ethernet
Magnetics
Clock
Audio
Serial
Host
Control
Clock
CobraNet CM-2
Module
Flash
Memory
Ethernet
Controller
CS18101