TNETE211

ThunderLAN

™ TO IEEE 802.12 PHYSICAL MEDIA DEPENDENT INTERFACE FOR

100VG-AnyLAN

SPWS019 – MAY 1995

1

POST OFFICE BOX 655303

POST OFFICE BOX 1443

The PCI Local Bus Specification, Revision 2.0,

should be used as a reference with this

document.

(TNETE100) Media Independent Interface

(MII) to a 100VG-AnyLAN IEEE 802.12

Physical Media Dependent (PMD) Interface

Device

100VG Architectures

IEEE 802.12-Compliant PMD Devices

the Medium Access Control (MAC) or

Repeater MAC (RMAC) and the PMD Device

Reception by Providing a 4-Channel Stream

Structure at the MII

Microsoft

™ Advanced Power Management

(JTAG)

Surface-Mount Package

(PN Suffix)

0

_C to 70_C

PCI

Bus

TNETE100

ThunderLAN

TNETE211

Physical Media

Independent

(PMI) Device

100VG-

AnyLAN

Physical Media

Dependent Device

(PMD)

Figure 1. Typical Application

description

The TNETE211 interfaces the ThunderLAN TNETE100’s IEEE 802.3u media independent interface to an

IEEE 802.12 physical media-dependent device for 100VG-AnyLAN operation. The TNETE211 is responsible

for quartet channeling, scrambling the transmission data into five-bit data quintets, and encoding the resulting

quintets into six-bit (5B6B) symbols. The TNETE211 also adds the preamble, start-frame delimiter, and

end-frame delimiter to each channel.

Quartet channeling refers to the process of dividing the MAC frame data octets into five-bit data quintets and

alloting them sequentially among the four transmission pair channels. The data scrambler alters the five-bit

quintet into a randomized bit pattern which is helpful in reducing radio-frequency interference and signal cross

talk between channels. The 5B6B symbol encoding transforms the five-bit randomized pattern into

predetermined six-bit symbols. This provides a balanced data pattern with an equal number of zeroes and ones

for clock transition synchronization for receive circuitry. This symbol encoding also has the added benefit of

being an error-checking mechanism.

Compliant with IEEE Standard 1149.1-1990 (JTAG), the TNETE211 provides a five-pin test-access port that is

used for boundary-scan testing.

The TNETE211 is available in an 80-pin plastic quad flat package.

† IEEE Standard 1149.1–1990, IEEE Standard Test Access Port and Boundary-Scan Architecture

ThunderLAN is a trademark of Texas Instruments Incorporated.

Microsoft is a trademark of Microsoft Corporation.

ADVANCE INFORMATION concerns new products in the sampling or

preproduction phase of development. Characteristic data and other

specifications are subject to change without notice.

Copyright

© 1995, Texas Instruments Incorporated