Product Summary

The SMSC COM90C66 is a special purposecommunications controller for interconnectingprocessors and intelligent peripherals using theARCNET Local Area Network. The COM90C66is unique in that it integrates the core ARCNET logic found in Standard Microsystems' originalCOM90C26 and COM90C32 with an on-chip 2Kx 8 RAM, as well as the 16-bit data bus interfacefor the IBM PC/AT. Because of the inclusion ofthe RAM buffer in the COM90C66, a complete ARCNET node can be implemented with only one or two additiona lICs(8-or16-bitapplications, respectively) and a media drivercircuit. The ARCNET core remains functionallyuntouched,eliminatingvalidationandcompatibility concerns. The enhancements existin the integration and the performanceof the device. Maximum integration has been achievedby including the 2K x 8 RAM buffer on the chip,providing the immediate benefits of a lowerdevice pin count and less board components.

Parametrics

MAXIMUM GUARANTEED RATINGS：
(1)Operating Temperature Range:0℃ to +70℃; (2)Storage Temperature Range:-55℃ to +150℃; (3)Lead Temperature (soldering, 10 seconds):+325℃; (4)Positive Voltage on any pin, with respect to ground:VCC+0.3V; (5)Negative Voltage on any pin, with respect to ground:-0.3V; (6)Maximum VCC:+7V

Features

(1)ARCNET LAN Controller/Transceiver/Support Logic/Dual-Port RAM; (2)Integrates SMSC COM90C65 with 16-Bit Data Bus, Dual-Port RAM, and Enhanced Diagnostics Circuitry; (3)Includes IBM PC/AT Bus Interface Circuitry; (4)Supports 8- and 16-Bit Data Buses; (5)Full 2K x 8 On-Chip Dual-Port Buffer RAM; (6)Zero Wait State Arbitration for Most AT Buses; (7)SMSC COM90C26 Software Compatible; (8)Command Chaining Enhances Performance; (9)Supports Memory Mapped and Sequential I/O Mapped Access to the Internal RAM Buffer; (10)Compatible with the SMSC HYC9058/68/ 88 (COAX and Twisted Pair Drivers); (11)Token Passing Protocol with Self Reconfiguration Detection; (12)Variable Data Length Packets; (13)16 Bits CRC Check/Generation; (14)Includes Address Decoding Circuitry for On-Chip RAM, PROM and I/O; (15)Supports up to 255 Nodes; (16)Contains Software Accessible Node IDRegister; (17)Compatible with Various Topologies (Star,Tree, Bus, ...); (18)On-Board Crystal Oscillator and Reset Circuitry; (19)Low Power CMOS, Single +5V Supply

Diagrams

<IMG border=0 src="http://www.seekic.com/uploadfile/ic-mfg/201271955555731.jpg">