• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 33 subscribers
  • Views 353 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

DS90UB929-Q1EVM: External Local EDID(EEPROM)configure

Amy Luo
Expert 6895 points
Part Number: DS90UB929-Q1EVM

Hi team,

One of our customer's issues, I'm forwarding it below, could you please provide your support 

There are four EDID configurations:

1、We choose the first scheme External local EDID (EEPROM).
     The selected EEPROM chip model is BR24T128-W, the package is DIP-T8, 128K memory (16K*8), 1.6V~5.5V power supply, and the highest frequency of IIC is 400KHZ. Please check with TI to see if it applies.

2、The configuration of MODE_SEL [1:0] is as follows: please confirm whether the configuration is correct

EDID_SEL: 1
AUX_I2S: 0
EXT_CTL: 0
COAX: 0
REM_EDID_LOAD: 0

J10 is an HDMI interface, and now there are the following questions:

1) Whether the 929 chip can read and write the external EEPROM
2) Whether the EDID information in the EEPROM is directly read by the host through the HDMI interface, or is the EDID information in the EERPROM read first through the 929 chip and then sent to the host
3) In what format is the EDID information stored in the EEPROM

Best Regards,

Amy Luo

  • 0
    TI__Mastermind 25735 points

    Hi Amy,

    I will look into this and get back to you in 1-2 days.

    Regards,

    Ben

  • 0 in reply to Ben Dattilo
    TI__Mastermind 25735 points

    Hi Amy,

    Amy Luo said:
    Please check with TI to see if it applies.

    I am not familiar with this particular device, but it seems the package type and bit format are correct for our EVMs.

    Amy Luo said:
    1) Whether the 929 chip can read and write the external EEPROM

    When connected to the DCC lines of the HDMI input as is the case in our EVM, the 929 cannot read or write to the external EEPROM

    Amy Luo said:
    2) Whether the EDID information in the EEPROM is directly read by the host through the HDMI interface, or is the EDID information in the EERPROM read first through the 929 chip and then sent to the host

    In the case I described above, the EEPROM is read by the host through the HDMI interface. The 929 never receives information directly from the EEPROM.

    Amy Luo said:
    3) In what format is the EDID information stored in the EEPROM

    Can you clarify what you mean here? There is an example of EDID data in the 929 datasheet (Section 7.3.4.4) that may help you to understand this format. Other specific addressing information would be found in the EEPROM datasheet.

    Regards,

    Ben

  • 0 in reply to Ben Dattilo
    TI__Expert 6895 points

    Hi Ben,

    Thank you very much for your response. The customer has additional questions：

    1: Whether the MOD_SEL switch controls the selection of DDC_SDA and DDC_SCL links.
    2: After setting MOD_SEL, when HDMI reads data, it is found that there is an error in the data, it seems that both 929 and EEPROM have responded to it. Whether the MOD_SEL setting is invalid.
    3: How to realize the point-to-point communication between HDMI and EEPROM.

    Best Regards,

    Amy

  • 0 in reply to Amy Luo
    TI__Guru 64240 points

    Hi Amy,

    Ben is out of office today. He will resume support on your questions tomorrow, thanks for your patience.

    Regards,

    Logan

  • +1 in reply to Amy Luo
    TI__Mastermind 25735 points

    Hi Amy,

    Amy Luo said:
    1: Whether the MOD_SEL switch controls the selection of DDC_SDA and DDC_SCL links.

    Not directly, but EDID_SEL determines whether an external local EDID is used. In this case, the DDC lines are used to communicate with the EEPROM.

    Amy Luo said:
    2: After setting MOD_SEL, when HDMI reads data, it is found that there is an error in the data, it seems that both 929 and EEPROM have responded to it. Whether the MOD_SEL setting is invalid

    I think the MODE_SEL settings you provided previously are correct based on the setup you have described. Registers 0x4F  (BRIDGE_CTL), 0x50 (BRIDGE_STS), and 0x51 (EDID_ID) would be helpful to understand the error that is occurring.

    Amy Luo said:
    3: How to realize the point-to-point communication between HDMI and EEPROM.

    I am not sure I understand what you are asking here. Can you elaborate?

    Regards,

    Ben