am79c981 Advanced Micro Devices, am79c981 Datasheet - Page 13

• Manufacturer Part Number: am79c981
• Description: Integrated Multiport Repeater Plus? Imr+? ??9
• Manufacturer: Advanced Micro Devices

Repeater MAC Interconnection
Because all repeated data in the IMR+ chip or multi-
IMR+ chip design is available on the Expansion Port, all
network traffic can be monitored by an external Media
Access Controller (MAC) device such as the Am7990,
Am79C900, Am79C940, or Am79C960. A repeater with
such a controller is capable of providing extensive hub
management functions, as well as being addressable as
a network node. The MAC device can gather statistics
and data concerning the state of the hub and the
ARST
Q0
Q1
Q2
Q3
Q4
Q5
Q6
DONE_COUNT
PALCE22V10
20 MHz Osc.
Counter
X1
NEW96
TCK
IMR+1
RST
Figure 2. Expandable Modular Repeater
DONE_COUNT
NEW96
X1
PRELIMINARY
IMR+2
Am79C981
PALCE16V8
Am79C960 PCnet-ISA
Arbiter
Am79C900 ILACC
Am79C940 MACE
Am7990 LANCE
RST
network, and the network addressability allows a remote
management station to monitor this statistical data and
to request actions to be performed by the repeater (i.e.
port enable/disable).
Figure 2 shows how to interface a repeater based on
multiple IMR+ devices to an Ethernet controller such as
the Am79C900 ILACC or the Am7990 LANCE. For more
information on this design, refer to AMD’s IEEE 802.3
Repeater Technical Manual, PID# 17314A.
or
CDT
14396C-033A
X1
CDT
PALCE16V8
Interface
IMR+n
ACKCLK
RTSCLK
RST
17306B-6
RCKEN
AMD
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