The TNETX15AE performs the address-lookup function for either the TNETX3150/TNETX3150A or the TNETX3100 EthernetTM switch. The TNETX15AE device determines the addresses to use and match from the TNETX3150/TNETX3150A/TNETX3100 DRAM bus. The address-lookup table is maintained in external SRAM. The frame-matching and routing information is given to the TNETX3150/TNETX3150A/TNETX3100 through the external address-matching (EAM) interface. The TNETX15AE is designed to work in either unmanaged or managed mode. Unmanaged operation is accomplished through EEPROM support. Startup options are auto-loaded into the TNETX15AE registers using the EEPROM interface. If the TNETX15AE is initialized by automatic loading from the EEPROM, it begins operation automatically.