KSZ8842-16MVL TR Micrel, KSZ8842-16MVL TR Datasheet - Page 31

• Manufacturer Part Number: KSZ8842-16MVL TR
• Description: Ethernet ICs 2-Port Ethernet Switch/Repeater + Generic (8, 16-bit) bus interface(Lead Free)
• Manufacturer: Micrel

Specifications of KSZ8842-16MVL TR

• Rohs: yes
• Product: Ethernet Switches
• Package / Case: PQFP-128
• Mounting Style: SMD/SMT

LinkMD Cable Diagnostics
The KSZ8842M LinkMD uses time domain reflectometry (TDR) to analyze the cabling plant for common cabling problems
such as open circuits, short circuits, and impedance mismatches.
LinkMD works by sending a pulse of known amplitude and duration down the MDI and MDI-X pairs and then analyzes the
shape of the reflected signal. Timing the pulse duration gives an indication of the distance to the cabling fault with a
maximum distance of 200m and an accuracy of +/–2m. Internal circuitry displays the TDR information in a user-readable
digital format in registers P1VCT[8:0] or P2VCT[8:0].
Note: cable diagnostics are only valid for copper connections –fiber-optic operation is not supported.
Access
LinkMD is initiated by accessing register P1VCT/P2VCT, the LinkMD Control/Status register, in conjunction with register
P1CR4/P2CR4, the 100BASE-TX PHY Controller register.
Micrel, Inc.
October 2007
Bypass Auto Negotiation
Start Auto Negotiation
and Set Link Mode
Force Link Setting
YES
NO
Figure 9. Auto Negotiation and Parallel Operation
Attempt Auto
Negotiation
31
Listen for 100BASE-TX
Link Mode Set ?
Link Mode Set
Operation
Parallel
Flow
Idles
Join
YES
NO
Listen for 10BASE-T Link
KSZ8842-16/32 MQL/MVL/MVLI/MBL
Pulses
M9999-102207-1.9