WBLXT9785HC.D0-865113 Cortina Systems Inc, WBLXT9785HC.D0-865113 Datasheet - Page 156

• Manufacturer Part Number: WBLXT9785HC.D0-865113
• Manufacturer: Cortina Systems Inc

Specifications of WBLXT9785HC.D0-865113

• Lead Free Status / RoHS Status: Compliant

LXT9785/LXT9785E
Datasheet
249241, Revision 11.0
16 April 2007
4.12.7
Table 49
Table 50
4.13
4.13.1
Cortina Systems
Boundary Scan Register
Each Boundary Scan Register (BSR) cell has two stages. A flip-flop and a latch are used
for the serial shift stage and the parallel output stage. There are four modes of operation
as listed in
Cortina Systems
Transceivers Specification Update (document number 249357) for the JTAG ID numbers.
BSR Mode of Operation
Supported JTAG Instructions
Cable Diagnostics Overview
Debugging cable problems increases the overall cost of owning and operating a local area
network. Cable Diagnostic tools were incorporated into the LXT9785/LXT9785E device to
help customers debug network cable problems. The Cable Diagnostic tools provide the
ability to detect severe cable problems, such as open and short circuits, and determine
the distance to the discontinuity.
Features
The following are three cases to consider for Cable Diagnostics:
An improperly terminated cable will not meet IEEE 802.3 return loss requirements.
Register 29 has been added to control cable testing and report cable testing results.
Cable Diagnostics provides a method to determine the distance to opens and shorts when
the link partner is inactive on the twisted-pair under test. The cable tests produce
undefined results if the link partner is transmitting signals. Implementation methods may
vary depending upon the system use requirements of Cable Diagnostics.
®
EXTEST
IDCODE
SAMPLE
High Z
Clamp
BYPASS
• Distance to a short circuit between wires of a single twisted-pair
• An open circuit
• Detection of an improperly terminated cable by the link partner.
Mode
LXT9785 and LXT9785E Advanced 8-Port 10/100 Mbps PHY Transceivers
Name
1
2
3
4
Table
0000 Hex
FFFE Hex
FFF8 Hex
FFCF Hex
FFEF Hex
FFFF Hex
®
49. Refer to the Identification Information section in the
LXT9785 and LXT9785E Advanced 8-Port 10/100 Mbps PHY
Code
System Function
Description
Capture
Update
Shift
External Test
ID Code Inspection
Sample Boundary
Force Float
Clamp
Bypass Scan
Description
BSR
BSR
ID REG
Bypass
BSR
Bypass
4.13 Cable Diagnostics
Data Register
Overview
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