EELXT901APC.A4 S L8L5 Cortina Systems Inc, EELXT901APC.A4 S L8L5 Datasheet - Page 16

• Manufacturer Part Number: EELXT901APC.A4 S L8L5
• Manufacturer: Cortina Systems Inc

Specifications of EELXT901APC.A4 S L8L5

• Lead Free Status / RoHS Status: Compliant

LXT901/907 — Universal 10BASE-T and AUI Transceivers
2.4
2.4.1
2.4.2
16
Figure 6. Collision Detection Function
Loopback Functions
Standard Twisted-Pair Loopback
The LXT901/907 provides the standard loopback function defined by the 10BASE-T specification
for the twisted-pair port. The loopback function operates in conjunction with the transmit function.
Data transmitted by the back-end is internally looped back within the LXT901/907 from the TXD
pin through the Manchester encoder/decoder to the RXD pin and returned to the back-end. This
standard loopback function is disabled when a data collision occurs, clearing the RXD circuit for
the TPI data. Standard loopback is also disabled during link fail and jabber states. The
LXT901/907 also provides three additional loopback functions.
External Loopback
An external loopback mode, useful for system-level testing, is controlled by the LEDC pin. When
LEDC is tied Low, the LXT901/907 disables the collision detection and internal loopback circuits
to allow external loopback. External loopback mode can be set on either twisted-pair or AUI ports.
DO=Idle+
XMIT=Disable
TPO=DO
A
DO=Active
TPI=Idle
Output
DI=DO
XMIT=Enable
DO=Active
TPI=Active
XMIT=Enable
DO=Active
TPI=Idle
Collision
TPO=DO
A
CI=SQE
DI=TPI
Idle
Power On
XMIT=Enable
DO=Idle
TPI=Active
DO=Active
TPI=Active
DI=TPI
Input
TPI=Idle
A
Rev. Date: June 19, 2001
Document #: 249097
Revision #: 002
Datasheet