COM20051I Datasheet, PDF (1/74 Pages) SMSC Corporation – Integrated Microcontroller and ARCNET (ANSI 878.1) Interface

COM20051I
Integrated Microcontroller and
ARCNET (ANSI 878.1) Interface
!" High Performance/Low Cost
!" Microcontroller Based on Popular 8051
Architecture
!" Intel 8051 Instruction Set Compatible
!" Drop-In Replacement for 80C32 PLCC
!" Network Supports up to 255 Nodes
!" Powerful Network Diagnostics
!" Maximum 507 Byte Packets
!" Duplicate Node ID Detection
!" Self-Configuring Network Protocol
FEATURES
!" Retains all 8051 Peripherals Including Serial I/O
and Two Timers
!" Utilizes ARCNET Token Bus Network Engine
!" Requires No Special Emulators
!" 5 Mbps to 156 Kbps Network Data Rate
!" Network Interface Supports RS-485, Twisted Pair,
Coaxial, and Fiber Optic Interfaces
!" Receive All Mode Allows Any Packet to Be
Received
GENERAL DESCRIPTION
The COM20051I is a low-cost, highly-integrated microcontroller incorporating a high-performance network controller
based on the ARCNET Token Bus Standard (ANSI 878.1). The COM20051I is based around the popular Intel 8051
architecture. The device is implemented using a microcontroller core compatible with the Intel 80C32 ROMless
version of the 8051 architecture. The COM20051I is ideal for distributed control networking applications such as
those found in industrial/machine controls, building/factory automation, consumer products, instrumentation and
automobiles.
The COM20051I contains many features that are beneficial for embedded control applications. The microcontroller is
a fully-functional 16MHz 80C32 that is comparable to the Intel 80C32 with 2 timers. In contrast to other embedded
controller/networking solutions, the COM20051I adds a fully-featured, robust, powerful, and simple network interface
while retaining all of the basic 8051 peripherals, such as the serial port and counter/timers.
In addition, the COM20051I supports an Emulation Mode that permits the use of a standard 80C32 emulator in
conjunction with the COM20051I to develop software drivers for the network core. ARCNET core is mapped to a
256-byte page of the External Data Memory Space of the 80C32. This provides for an easy interface between the
CPU and the ARCNET core. The networking core is based around an ARCNET Token Bus protocol engine
that provides highly-reliable and fault tolerant message delivery at data rates ranging from 5Mbps down to 156
Kbps with message sizes varying from 0 to 507 bytes. The ARCNET protocol offers a simple, standardized, and
easily-understood networking solution for any application. The network interface supports several media interfaces,
including RS-485, coaxial, and twisted pair in either bus or star topologies. The network interface incorporates
powerful diagnostic features for network management and fault isolation. These include duplicate node ID detection,
reconfiguration detection, receive all (monitor) mode, receiver activity, and token detection.
ORDERING INFORMATION
Order Number: COM20051ILJ P
44 Pin PLCC Package
SMSC DS – COM20051I
Rev. 03/27/2000