AX88615 ASIX [ASIX Electronics Corporation], AX88615 Datasheet - Page 4

• Manufacturer Part Number: AX88615
• Description: 5-Port 10/100BASE Ethernet Switch
• Manufacturer: ASIX [ASIX Electronics Corporation]

1.0 AX88615 Overview
1.1 General Description
The AX88615 is a 5-ports 10/100 Mbps Ethernet switch with MII PHY or RMII PHY. A low cost Fast Ethernet switch
can be implemented by using the AX88615 and low cost 64Kx32 SSRAM .
Data received from the MAC interface is stored in the external memory. All ports support multiple MAC addresses. The
switch provides a look-up table for 8K MAC addresses with two 64Kx32 SSRAMs. The AX88615 provides three frame
forwarding mode: store-and-forward mode, safe cut-through (fragment free) mode and dynamic-select-mode (auto). The
dynamic-select-mode means the switch selects optimizes mode for forwarding packages automatically according to
Network quality.
During transmission, the data is obtained from the buffer memory and routed to the destination port. For half-duplex
operation, the MAC control will back off and retransmit in accordance to the IEEE802.3 CSMA/CD if collision occurs.
The AX88615 provides two flow control methods. For half-duplex operation, an optional jamming based flow control is
available to avoid loss of data. This is also well known as back pressure. In the full-duplex mode, AX88615 utilizes
IEEE802.3X as the flow control mechanism.
1.2 AX88615 Block Diagram:
MII / RMII
MII / RMII
MII / RMII
MII / RMII
MII / RMII
PHY
PHY
PHY
PHY
PHY
AX88615P 5-Port 10/100Mb Switch Controller PRELIMINARY
P0 10/100 MAC
P1 10/100 MAC
P2 10/100 MAC
P3 10/100 MAC
P4 10/100 MAC
LED Interface
Fig - 1 AX88615 Block Diagram
4
Switch Fabric
High Speed
ASIX ELECTRONICS CORPORATION
64K*32 SSRAM
Routing /Learning
CONFIDENTIAL
Buffer Manager
Buffer Memory
Controller
Interface