SNLA431 January   2024 DP83TC812R-Q1 , DP83TC812S-Q1

 

  1.   1
  2.   Trademarks
  3. 1Preface
  4.   Notational Conventions
  5. 2Related Documentation
  6. 3Support Resources
  7. 4Troubleshooting the PHY Application
    1. 4.1  Schematic and Layout Checklist
    2. 4.2  Verify Successful Power-up of PHY
    3. 4.3  Peripheral Pin Checks
      1. 4.3.1 Probe the RESET_N pin
      2. 4.3.2 Probe the INH pin
      3. 4.3.3 Probe the CLKOUT pin
      4. 4.3.4 Probe the Serial Management Interface (MDC, MDIO) Pins
    4. 4.4  Register Dump Comparison
    5. 4.5  Verifying Strap Configurations
    6. 4.6  Check the MDI Signal
    7. 4.7  Link Up Failed Common Issues
    8. 4.8  Signal Quality Check
    9. 4.9  Power Up Timing
    10. 4.10 Loopback Testing
    11. 4.11 Debugging the MAC Interface
    12. 4.12 Verify Open Alliance PMA Compliance
    13. 4.13 Tools and References
      1. 4.13.1 DP83TC812 Register Access
      2. 4.13.2 DP83TC812 USB2MDIO Scripts
      3. 4.13.3 Extended Register Access
      4. 4.13.4 Software and Driver Debug on Linux
        1. 4.13.4.1 Commonly Seen Linux Terminal Outputs
  8. 5Conclusion

4.13.3 Extended Register Access

To read and write registers in extended register space, refer to the following procedures:

Write procedure for MMD "1F" registers:

write reg<000D> = 0x001F

write reg<000E> = <address>

write reg<000D> = 0x401F

write reg<000E> = <value>

Read procedure for MMD "1F" registers:

write reg<000D> = 0x001F

write reg<000E> = <address>

write reg<000D> = 0x401F

read reg<000E>

Note: To read/write MMD "1" registers, replace 1F with 01.