Datasheet

LAN8740A/LAN8740Ai
DS00001987A-page 78  2013-2015 Microchip Technology Inc.
4.2.19 CABLE LENGTH REGISTER
Index (In Decimal): 28 Size: 16 bits
Bits Description Type Default
15:12 Cable Length (CBLN)
This four bit value indicates the cable length. Refer to Section 3.8.11.2,
"Matched Cable Diagnostics" for additional information on the usage of this
field.
Note: This field indicates cable length for 100BASE-TX linked devices
that do not have an open/short on the cable. To determine the
open/short status of the cable, the TDR Patterns/Delay Control
Register and TDR Control/Status Register must be used. Cable
length is not supported for 10BASE-T links. Refer to Section
3.8.11, "Cable Diagnostics" for additional information.
RO 0000b
11:0 RESERVED RO -