ASIX ELECTRONICS CORPORATION First Released Date : APR/09/1999
2F, NO.13, Industry East Rd. II, Science-based Industrial Park, Hsin-Chu City, Taiwan, R.O.C.
TEL: 886-3-579-9500 FAX: 886-3-579-9558 http://www.asix.com.tw
AX88872P
10/100BASE Dual Speed “ Swipeater ” Controller
10/100BASE Dual Speed 8-Port Repeater with 4-Port Switch
Document No.: AX872-13 / V1.3 / Aug. 11 ’ 99
Features
• S upport 8 10/100Mbps RMII I/F repeater ports and
2 10/100Mbps RMII/MII switch ports
• IEEE 802.3u repeater compatible
• Support virtual switch mode and Master/Slave
m ode for the cascade application
• Build in 4-ports 10/100Mbps Switch engine with
following features
ü Low cost SSRAM interface to reduce system cost
ü One or two 64K*32bit SSRAM to buffer packets
ü 4/8 K MAC Address Entry Table is supported
ü Auto learning and filtering
ü Aging the MAC Address table is supported
optionally
ü Three forwarding modes are supported : Store-
a n d -Forward, Fragment-Free and Auto -Forward
ü Flow-control is supported optionally.
ü 802.3x flow control is supported in full duplex
mode
ü Back-pressure base flow control is supported in
half duplex mode
ü Ext. Buffer Memory auto testing
ü Routing and Learning at wire speed (148800
packets/sec at 100Mbps)
• Up-to 4 repeaters can be cascaded for vertical
expansion
• Up-to 3 chips can be cascaded locally for horizontal
expansion
• All ports can be separately isolated or partitioned in
response to fault condition
• Separate jabber and partition state machines for
each port
• Per-port LED display for Jabber, Partition,
Activity. RAM test fail and collision, buffer
utilization (%) and global traffic utilization (%) for
10/100Mbps presentation
• Power on LED diagnosis. All the LED display will
follow the “ ON-OFF-ON-OFF-Normal ” operation
procedure during/after power on reset
• 50MHz Operation, 3.3volt and 208-pin PQFP
Product description
The AX88872 10/100Mbps Dual Speed “ Swipeater ” Controller is “ a dual speed repeater with build in 4-port s
switch function ” It is design for low cost dumb HUB application. The AX88872 directly supports up-to eight
10/100Mbps automatic links RMII interfaces. Maximum up-to 96 repeater ports can be constructed by stacking 1
AX88872 and 2 AX88873 chips horizontally and then cascading 4 horizontal board s vertically. About the build in
4-port switch : T he switch port 3 is fixed to 10Mbps speed and connect s to 10Mbps repeater segment, The switch port 2
is fixed to 100Mbps and connect s to 100M repeater segment. The switch ports 0 and 1 are connected to external MII
or RMII interfaces for various applications. For example, one port is use d for down link and the other is used for up
link to exten d the network topology. The other case is one port for up link and the other port f or server. The AX88872
is designed base on IEEE 802.3u clause 27 “ Repeater for 100Mb/s base-band networks ” It is fully compatible with
IEEE 802.3u standard. Please refer Ax873- 12 .doc to get more information about AX88873.
System Block Diagram
Always contact ASIX for possible updates before starting a design.
This data sheet contain s new products information. ASIX ELECTRONICS reserves the rights to modify the product specification without notice. No
liability is assumed as a result of the use of this product. No rights under any patent accompany the sale of the product.
AX88873 #1
Repeater Controller
Buffer
100Mbps horizontal cascade
10Mbps and 100Mbps Vertical cascade up to 4 stacks
AX88873 #0
Repeater Controller
AX88872 #0
Swipeater Controller
10Mbps horizontal cascade
2 Quad RMII PHY 2 Quad RMII PHY 2 Quad RMII PHY
PHY for Up-link
PHY for Down-link or Server