The DM9000A is a fully integrated and cost-effective low pin count single chip Fast Ethernet controller with a general processor interface, a 10/100M PHY and 4K Dword SRAM. It is designed with low power and high performance process that support 3.3V with 5V IO tolerance. The DM9000A supports 8-bit and 16-bit data interfaces to internal memory accesses for various processors. The PHY of the DM9000A can interface to the UTP3, 4, 5 in 10Base-T and UTP5 in 100Base-TX with AUTO-MDIX. It is fully compliant with the IEEE 802.3u Spec. Its auto-negotiation function will automatically configure the DM9000A to take the maximum advantage of its abilities. The DM9000A also supports IEEE 802.3x fullduplex flow control..