TLK110 Datasheet, PDF (13/104 Pages) Texas Instruments – Industrial Temp, Single Port 10/100Mbs Ethernet Physical Layer

TLK110
www.ti.com
SLLS901A – DECEMBER 2011 – REVISED FEBRUARY 2012
AN_EN
1
1
1
Table 3-1. Auto-Negotiation Modes (continued)
AN_1
0
1
1
AN_0
1
0
1
Forced Mode
100Base-TX, Half/Full-Duplex
10Base-T, Half Duplex
100Base-TX, Half Duplex
10Base-T, Half/Full-Duplex
100Base-TX, Half/Full-Duplex
The Auto-Negotiation function can also be controlled by internal register access using registers as defined
by the IEEE 802.3u specification. For further detail regarding Auto-Negotiation, see Clause 28 of the IEEE
802.3u specification.
3.5 Auto-MDIX
The TLK110 device automatically determines whether or not it needs to cross over between pairs so that
an external crossover cable is not required. If the TLK110 interoperates with a device that implements
MDI/MDIX crossover, a random algorithm as described in IEEE 802.3 determines which device performs
the crossover.
Auto-MDIX is enabled by default and can be configured via jumper, SW Strap register SWSCR1 (0x09h),
bit 14 or via register PHYCR (0x19h), bit 15.
The crossover can be manually forced through bit 14 of the PHYCR (0x19h) register. Neither Auto-
Negotiation nor Auto-MDIX is required to be enabled in forcing crossover of the MDI pairs.
Auto-MDIX can be used in the forced 100Base-TX mode. Because in modern networks all the nodes are
100Base-TX, having the Auto-MDIX working in the forced 100Base-TX mode resolves the link faster
without the need for the long Auto-Negotiation period.
3.6 MII Isolate Mode
The TLK110 can be put into MII-Isolate mode by writing bit 10 of the BMCR register.
When in the MII-Isolate mode, the TLK110 does not respond to packet data present at the TXD[3:0],
TX_EN inputs, and presents a high impedance on the TX_CLK, RX_CLK, RX_DV, RX_ER, RXD[3:0],
COL, and CRS outputs. When in isolate mode, the TLK110 continues to respond to all management
transactions.
When in isolate mode, the PMD output pair does not transmit packet data, but continues to source
100Base-TX scrambled idles or 10Base-T normal link pulses. The TLK110 can auto-negotiate or parallel
detect on the receive signal at the PMD input pair. A valid link can be established for the receiver even
when the TLK110 is in Isolate mode.
Copyright © 2011–2012, Texas Instruments Incorporated
Submit Documentation Feedback
Product Folder Link(s): TLK110
Hardware Configuration
13