SNLA246C October   2015  – April 2024 DP83867CR , DP83867CS , DP83867E , DP83867IR , DP83867IS

 

  1.   1
  2.   Trademarks
  3. 1Introduction
  4. 2Troubleshooting the Application
    1. 2.1 Read and Check Register Values for Basic Health Check
    2. 2.2 Schematic and Layout Checklist
    3. 2.3 Component Checklist
      1. 2.3.1 Magnetics
      2. 2.3.2 Crystal / Oscillator
    4. 2.4 Peripheral Pin Checks
      1. 2.4.1 Power Supplies
      2. 2.4.2 RBIAS Voltage and Resistance
      3. 2.4.3 Probe the XI Clock
      4. 2.4.4 Probe the RESET_N Signal
      5. 2.4.5 Probe the Strap Pins During Initialization
      6. 2.4.6 Probe the Serial Management Interface Signals (MDC, MDIO)
      7. 2.4.7 Probe the MDI Signals
    5. 2.5 Link Quality Check
    6. 2.6 Built-in Self Test With Various Loopback Modes
    7. 2.7 Debugging MAC Interface
      1. 2.7.1 RGMII Debug
      2. 2.7.2 SGMII Debug
  5. 3Application Specific Debugs
    1. 3.1 Improving Link-up Margins for Short Cables
    2. 3.2 Improving Link Margins across Different Channels
    3. 3.3 Link up in 100Mbps Full Duplex Force Mode
    4. 3.4 Unstable Link Up Debug in 1Gbps communication
    5. 3.5 DP83867PHY and DP83867PHY Cannot Link Up in 1Gbps
    6. 3.6 Compliance Debug
    7. 3.7 EMC Debug
    8. 3.8 Tools and References
      1. 3.8.1 DP83867 Register Access
      2. 3.8.2 Extended Register Access
  6. 4Conclusion
  7. 5References
  8. 6Revision History

3.4 Unstable Link Up Debug in 1Gbps communication

If repeating link up and link down between Dp83867 and another Link Partner behavior occur, please follow this session for debug:

  1. Write register 0x001F to 4000 (software reset) and see if you are able to link up.
  2. Check if DP83867 is able to link up with another TI giga-bit PHY.
  3. Check the Schematic and Layout Checklist session to make sure the board design follow the recommendation.
  4. Read register 0x0013 bit[12] and register 0x0011 bit[12]. If both registers indicate page received in 1Gbps communication. Write register 0x01D5 = F508 to change DP83867PHY from low power mode to normal operational mode.
begin
// Check page recieved in 1Gbps communication
0012
0013
// changing from lower power mode to normal operational mode
01D5 F508
end