DM9081
10BASE-T Hub Controller
General Description
The 10BASE-T Hub Controller (DM9081) provides a
system level solution for designing IEEE-compliant 802.3
repeaters that incorporate 10BASE-T transceivers. This
device integrates the repeater functions specified by
section 9 of the IEEE 802.3 standard. The Twisted Pair
transceiver is compliant with 10BASE-T standards. The
DM9081 provides eight integral Twisted Pair Media
Attachment Units (MAUs) and two Attachment Unit
Interface (AUI) ports in a 100-pin QFP package.
The total number of ports per repeater unit can be
increased by connecting multiple DM9081 chips via
their expansion ports. The DM9081 supports LED drivers
to monitor port status. It displays Link, Carrier Sense,
Collision, Partition, and Bit Rate Error Status. In
minimum mode, Link, Carrier Sense, and Collision Status
can be displayed without external TTL devices.
Block Diagram
PREAMBLE
TX
MUX
JAM SIGNAL
FIFO
RX_CLK
DATA IN
MANCHESTER
DECODER
RX
MUX
AUI
PORT1
RXP1
RXN1
CDP1
CDN1
TXP1
TXN1
RXP2
RXN2
CDP2
CDN2
TXP2
TXN2
RXD0+
RXD0-
TPO0+
DTPO0+
DTPO0-
TPO0-
AUI
PORT2
PLL
TP
PORT0
NRZ DATA
MUX
MANCHESTER
ENCODER
DATA OUT
EXPIN#
EXPOUT#
DAT
EXPANSION
PORT
STATE
MACHINE
*
*
*
*
*
LED PORT2
AUI2_CRS_LED
AUI1_CRS_LED
COL_LED
TP
PORT7
LED PORT1
LED_LATCH
TCK
TP_LINK_LED
TP_PAR_LED
TRAFFIC_LED
TP_JAB_LED
TP_POL_LED
TP_BIT_LED
AUI_LED
TIMER
RXD7+
RXD7-
TPO7+
DTPO7+
DTPO7-
TPO7-
Final
Version: DM9081-DS-F01
April 22, 1997
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