TNETX3100 datasheet(31/80 Pages) TI1

31 / 80 page

TNETX3100

ThunderSWITCH™ 10-PORT 10-/100-MBIT/S ETHERNET™ SWITCH

SPWS031D – JUNE 1997 – REVISED OCTOBER 1997

POST OFFICE BOX 655303

• DALLAS, TEXAS 75265

SIO/XCTRL register at 0x00A1

XCTRL REGISTER

SIO REGISTER

BIT

Reserved

CUT100

RXARB

BRUN

Reserved

ECLOK

ETXEN

EDATA

Initial Values After Reset

–

BIT

NAME

FUNCTION

Reserved

Reserved. Not implemented (reads as zero).

CUT100

Single-buffer cut-through operation on 100-Mbit/s ports only. CUT100 = 1 disables single-buffer cut-through

operation for frames received on 10-Mbit/s source ports. A frame is transmitted only when two buffers are

transferred to the transmit FIFO or an end of frame (prior to two buffers) is received. Although it increases latency

on 10-Mbit/s ports, enabling CUT100 reduces the probability of dropping frames due to FIFO underrun on

100-Mbit/s ports. When CUT100 = 0, all ports operate in single-buffer cut-through mode.

RXARB

Receive arbitration mode. RXARB = 1 ensures that no frames are dropped during bursty conditions. When RXARB

= 0, errored frames can be transmitted. To ensure proper operation, set RXARB to 1.

BRUN

Broadcast to unassigned ports. If no port address is matched, and BRUN = 1, the TNETX3100 broadcasts a unicast

frame to all ports with unassigned addresses (ports that are enabled but do not have a port address). When BRUN

= 0, all unmatched unicast frames are sent to the uplink port. BRUN = 0 if an external address-lookup device is

used. The external address-lookup device provides the function by itself.

Reserved

ECLOK

EEPROM SIO clock. ECLOK controls the state of the ECLK terminal. When ECLOK = 1, ECLK is asserted. When

ECLOK = 0, ECLK is deasserted. ECLOK also is used to determine the state of the EEPROM interface. If the

EEPROM port is disabled, ECLOK is always read as a 0, even if a value of 1 is written to the bit. The TNETX3100

detects that the EEPROM port is disabled by sensing the state of the EDIO terminal during reset. If EDIO is read

as a 0 during reset (due to an external pulldown resistor), the EEPROM interface is disabled and no attempt is made

to read configuration information.

ETXEN

EEPROM SIO transmit enable. ETXEN controls the direction of the EDIO terminal. When ETXEN = 1, EDIO is

driven with the value in the EDATA bit. When ETXEN = 0, EDATA is loaded with the value on the EDIO terminal.

EDATA

EEPROM SIO data. EDATA is used to read or write the state of the EDIO terminal. When ETXEN = 1, EDIO is driven

with the value in EDATA. When ETXEN = 0, EDATA is loaded with the value on the EDIO terminal.

device code register at 0x00A3 (DIO)

BIT

Device Identification Code

BIT

NAME

FUNCTION

7–0

DEVCODE

Device type code for the device. The DEVCODE field is read only and identifies the type of ThunderSWITCH

device. The standard ThunderSWITCH (TNETX3150) has a code of 0x00. Tiny ThunderSWITCH (TNETX3100)

has a code of 0x01.

TNETX3100 Datasheet(PDF) 31 Page - Texas Instruments

TNETX3100 Datasheet(HTML) 31 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80

Datasheet Download

Link URL