SNLA443A December   2023  – August 2025 DP83869HM

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1DP83869 Application Overview
  5. 2Troubleshooting the Application
    1. 2.1 Schematic and Layout Checklist
    2. 2.2 Device Health Checks
      1. 2.2.1 Voltage Checks
      2. 2.2.2 Probe the RESET_N Signal
      3. 2.2.3 Probe RBIAS
      4. 2.2.4 Probe the XI Clock
      5. 2.2.5 Probe the Strap Pins During Initialization
        1. 2.2.5.1 Configuring Correct Operational Mode
      6. 2.2.6 Probe the Serial Management Interface (MDC, MDIO)
        1. 2.2.6.1 Read and Check Register Values
    3. 2.3 MDI Health Checks
      1. 2.3.1 Magnetics
      2. 2.3.2 Probe the MDI Signals
      3. 2.3.3 Check the Link Quality
        1. 2.3.3.1 Improving Short Cable Link Margin
        2. 2.3.3.2 Improving Inter-channel Link Margin
      4. 2.3.4 Compliance
    4. 2.4 MII Health Checks
      1. 2.4.1 MII Check
      2. 2.4.2 RGMII Check
      3. 2.4.3 SGMII Check
    5. 2.5 Loopback and PRBS
      1. 2.5.1 Loopback Modes
      2. 2.5.2 Transmitting and Receiving Packets with the MAC
      3. 2.5.3 Transmitting and Receiving Packets with BIST
  6. 3Operational Mode Clarification
    1. 3.1 Bridge Modes
    2. 3.2 Fiber Configuration
      1. 3.2.1 Fiber Registers
      2. 3.2.2 Media Converter LED Behavior
  7. 4Tools and References
    1. 4.1 Extended Register Access
      1. 4.1.1 Read (No Post Increment) Operation
      2. 4.1.2 Write (No Post Increment) Operation
    2. 4.2 Software and Driver Debug on Linux
      1. 4.2.1 Common Terminal Outputs
  8. 5Summary
  9. 6References
  10. 7Revision History

4.1.2 Write (No Post Increment) Operation

To write a register in the extended register set:

Instruction Example: Set reg 0x0170 = 0C50

1. Write the value 0x001F (address function field = 00, DEVAD = 31) to register REGCR (0x0D).

 Write register 0x0D to value 0x001F

2. Write the desired register address to register ADDAR (0x0E).

 Write register 0x0E to value 0x0170

3. Write the value 0x401F (data, no post increment function field = 01, DEVAD = 31) to register REGCR.

 Write register 0x0D to value 0x401F
4. Write the content of the desired extended register set register to register ADDAR.

Write register 0x0E to value 0x0C50

Subsequent writes to register ADDAR (step 4) continue to rewrite the register selected by the value in the address register.

Note: Steps (1) and (2) can be skipped if the address register was previously configured.