10 Mbps ARCNET (ANSI 878.1) Controller with 2Kx8 On-Chip RAM
Datasheet
Chapter 1
General Description
SMSC's COM20022I 3V 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 and embedded control environments using an
ARCNET protocol engine. The small 48 pin package, flexible microcontroller and media interfaces, eight-
page message support, and extended temperature range of the COM20022I 3V make it the only true
network controller optimized for use in industrial and embedded 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 10 Mbps when
using the COM20022I 3V. 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 10 Mbps maximum data rate, and the
internal diagnostics make the COM20022I 3V the highest performance embedded communications device
available. With only one COM20022I 3V and one microcontroller, a complete communications node may
be implemented.
NOTE:
For more details on the ARCNET protocol engine and traditional dipulse signaling schemes, please
refer to the ARCNET Local Area Network Standard, or the ARCNET Designer's Handbook, available
from Datapoint Corporation.
Revision 03-08-07
Page 6
SMSC COM20022I 3.3V Rev.C
DATASHEET
SMSC [ SMSC CORPORATION ]
