Specifications

TNETX4090
ThunderSWITCH II

9-PORT 100-/1000-MBIT/S ETHERNET

SWITCH
SPWS044E – DECEMBER 1997 – REVISED AUGUST 1999
18
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
DIO interface description
The DIO is a general-purpose interface that is used with a range of microprocessor or computer system
interfaces. The interface is backward compatible with the existing TI ThunderSWITCH products. The DIO
provides new signals to support external DMA controllers for improved performance.
This interface configures the switch using the attached CPU, and to access statistics registers (see Table 2).
DIO accesses the NM port to allow frame data to be transferred between the CPU and the switch to support
spanning tree, SNMP, and RMON. The CPU reads and writes packets directly under software control or an
external DMA controller can be used to improve performance. See
TNETX4090 Programmer’s Reference
Guide , literature number SPAU003, for description of registers.
Table 2. DIO Internal Register Address Map
BYTE 3 BYTE 2 BYTE 1 BYTE 0
DIO
ADDRESS
Port1Control Port0Control 0x0000
Port3Control Port2Control 0x0004
Port5Control Port4Control 0x0008
Port7Control Port6Control 0x000C
Reserved Port8Control 0x0010
Reserved 0x0014–0x003C
Reserved UnkVLANPort MirrorPort UplinkPort 0x0040
Reserved AgingThreshold 0x0044
Reserved 0x0048–0x004C
NLearnPorts 0x0050
TxBlockPorts 0x0054
RxUniBlockPorts 0x0058
RxMultiBlockPorts 0x005C
UnkUniPorts 0x0060
UnkMultiPorts 0x0064
UnkSrcPorts 0x0068
NewVLANIntPorts 0x006C
Reserved 0x0070–0x007C
TrunkMap3 TrunkMap2 TrunkMap1 TrunkMap0 0x0080
TrunkMap7 TrunkMap6 TrunkMap5 TrunkMap4 0x0084
Trunk3Ports Trunk2Ports Trunk1Ports Trunk0Ports 0x0088
Reserved RingPorts 0x008C
Reserved 0x0090–0x009C
DevCode Reserved SIO Revision 0x00A0
DevNode[23:16] DevNode[31:24] DevNode[39:32] DevNode[47:40] 0x00A4
Reserved DevNode[7:0] DevNode[15:8] 0x00A8
MCastLimit 0x00DC
RamStatus RamControl Reserved 0x00E0
Reserved 0x00E4
PauseTime100 PauseTime10 0x00E8
PauseTime1000 Reserved 0x00EC
Reserved FlowThreshold 0x00F0
Reserved LEDControl 0x00F4