DP83261 Datasheet, PDF (1/132 Pages) National Semiconductor (TI) – BMAC Device (FDDI Media Access Controller)

October 1994
DP83261 BMAC^TM Device
(FDDI Media Access Controller)
General Description
The DP83261 BMAC device implements the Media Access
Control (MAC) protocol for operation in an FDDI token ring
The BMAC device provides a flexible interface to the
BSI-2^TM device The BMAC device offers the capabilities
described in the ANSI X3T9 5 MAC Standard and several
functional enhancements allowed by the Standard
The BMAC device transmits receives repeats and strips
tokens and frames It uses a full duplex architecture that
allows diagnostic transmission and self testing for error iso-
lation The duplex architecture also allows full duplex data
service on point-to-point connections Management soft-
ware is also aided by an array of on chip statistical counters
and the ability to internally generate Claim and Beacon
frames without program intervention A multi-frame stream-
ing interface is provided to the system interface device
Features
Y _{Full duplex operation with through parity}
Y _{Supports all FDDI ring scheduling classes (asynchro-}
nous synchronous restricted asynchronous and
immediate)
Y _{Supports individual group short long and external}
addressing
Y _{Generates Beacon Claim and Void frames without}
intervention
Y _{Provides extensive ring and station statistics}
Y _{Provides extensions for MAC level bridging}
Y _{Provides separate management interface}
Y _{Uses low power microCMOS}
TL F 10387 – 1
FIGURE 1-1 FDDI Chip Set Block Diagram
TRI-STATE is a registered trademark of National Semiconductor Corporation
BSI-2TM BMACTM PLAYERaTM CDDTM and CRDTM are trademarks of National Semiconductor Corporation
C1995 National Semiconductor Corporation TL F 10387
RRD-B30M105 Printed in U S A