SNLA443 December   2023 DP83869HM

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1DP83869 Application Overview
  5. 2Troubleshooting the Application
    1. 2.1 Configuring Correct Operational Mode
    2. 2.2 Schematic and Layout Checklist
    3. 2.3 Component Checklist
    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 Built-In Self Test with Various Loopback Modes
    6. 2.6 Debugging MAC Interface
      1. 2.6.1 RGMII
      2. 2.6.2 SGMII
  6. 3Operational Mode Clarification
    1. 3.1 Bridge Modes
    2. 3.2 Fiber Configuration
      1. 3.2.1 Fiber Registers
  7. 4Tools and References
    1. 4.1 DP83869HM Register Access
    2. 4.2 Extended Register Access
      1. 4.2.1 Read (No Post Increment) Operation
      2. 4.2.2 Write (No Post Increment) Operation
    3. 4.3 Software and Driver Debug on Linux
      1. 4.3.1 Common Terminal Outputs
  8. 5Summary
  9. 6References

Probe the MDI Signals

The DP83869 has four differential pairs to send data:

  • TD_P_A | TD_M_A
  • TD_P_B | TD_M_B
  • TD_P_C | TD_M_C
  • TD_P_D | TD_M_D
In OpMode: 000, RGMII to Copper, probing a channel allows you to see the link pulse which confirms the PHY is on and is attempting to link.

GUID-5E846689-66F8-48BE-8C72-8853251E70F5-low.gifFigure 2-6 100 Ohm Terminated Cable for MDI Signal Measurement
GUID-58CE164C-71FC-42DC-8F49-3F12541C2654-low.gifFigure 2-7 Connection Diagram for 1000M Terminated Cable
GUID-20231025-SS0I-LQTH-LHDB-TMV0LLXFNBKC-low.svg Figure 2-8 Link Pulse Waveform