AN2692 Freescale Semiconductor / Motorola, AN2692 Datasheet - Page 2

• Manufacturer Part Number: AN2692
• Description: MC9S12NE64 Integrated Ethernet Controller
• Manufacturer: Freescale Semiconductor / Motorola

Introduction
The MC9S12NE64 is a 16-bit MCU based on Freescale Semiconductor’s HCS12 CPU platform. It is the
first in a series of low-cost Ethernet-capable MCUs in a small package. The MC9S12NE64 provides a
complete, integrated, single-chip Ethernet solution. This application note provides a system overview of
the MC9S12NE64 and its integrated Ethernet controller. This discussion also describes how the
MC9S12NE64 fits into the network communication model of wired networks. This discussion describes
detailed setup for register configuration, initialization, and operation regarding the MC9S12NE64 Ethernet
capability; however, Freescale Semiconductor provides a free software driver for the MC9S12NE64
Ethernet controller, which greatly simplifies its setup and use. See
Connectivity Example Applications
Embedded devices with Ethernet capability can be implemented in a wide range of applications,
including:
The MC9S12NE64 provides a total solution for systems that:
Ethernet Network Overview
This section provides an overview of Ethernet basics and discusses how the MC9S12NE64 fits into the
network communication model of wired Ethernet networks.
Ethernet is commonly used in local area networks (LANs) for device connectivity because it is inexpensive
and fast. Ethernet is a technology used in LANs where a group of network devices share a common
communications medium. In this application note, the focus is wired LANs because the MC9S12NE64 is
designed for wired LANs. The most common communications medium, for wired LANs, is category 5 (cat-
5) un-shielded twisted pair (UTP) cable. Using Ethernet technology and the shared communications
medium allows the sharing of resources and data among connected devices on the network. Wired
Ethernet is becoming a widely used communication tool much like an SCI or USB.
The IEEE 802.3
device connected to the network has a unique hardware address. Because Ethernet uses a shared
medium, when one device transmits an Ethernet packet on the network (an Ethernet packet as defined
in the IEEE 802.3 standard is shown in
device on the network starts to process the packet to determine whether the packet is meant for it by
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Database data logging or queries
Web servers for remote embedded devices
Remote monitoring (data collection/diagnostics)
Control of remote devices
Use of email by remote device
Remote reprogramming of nonvolatile memory (FLASH)
Need Ethernet connectivity
Are end nodes on a network
Need Ethernet connectivity, but not necessarily the fastest data throughput
Need a low-cost Ethernet solution
Need a reduced component count and package size
standard defines how wired Ethernet works. Ethernet works on the basis that every
MC9S12NE64 Integrated Ethernet Controller, Rev. 0.2
Figure
2), every device on the network sees that message. Each
EMAC
and
EPHY
Freescale Semiconductor
sections for details.