COM20020I Datasheet, PDF (6/72 Pages) SMSC Corporation – 5Mbps ARCNET (ANSI 878.1) Controller with 2K x 8 On-Chip RAM

Chapter 1
5Mbps ARCNET (ANSI 878.1) Controller with 2K x 8 On-Chip RAM
Datasheet
General Description
SMSC's COM20020ID is a member of the family of Embedded ARCNET Controllers from Standard
Microsystems Corporation. The device is a general purpose communications controller for networking
microcontrollers and intelligent peripherals in industrial, automotive, and embedded control environments
using an ARCNET^® protocol engine. The small 28 pin package, flexible microcontroller and media
interfaces, eight- page message support, and extended temperature range of the COM20020ID make it
the only true network controller optimized for use in industrial, embedded, and automotive applications.
Using an ARCNET protocol engine is the ideal solution for embedded control applications because it
provides a deterministic token-passing protocol, a highly reliable and proven networking scheme, and a
data rate of up to 5 Mbps when using the COM20020ID.
A token-passing protocol provides predictable response times because each network event occurs within a
predetermined time interval, based upon the number of nodes on the network. The deterministic nature of
ARCNET is essential in real time applications. The integration of the 2Kx8 RAM buffer on-chip, the
Command Chaining feature, the 5 Mbps maximum data rate, and the internal diagnostics make the
COM20020ID the highest performance embedded communications device available. With only one
COM20020ID and one microcontroller, a complete communications node may be implemented.
Revision 12-05-06
Page 6
DATASHEET
SMSC COM20020I Rev D