• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 33 subscribers
  • Views 182 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

DS90UB935-Q1: CHKSUM_ERR fault-screen flicker

Sherry Liang
Genius 10255 points
Part Number: DS90UB935-Q1

Dear team,

My customer encounters screen flicker phenomenon, and they use our 935&954.

In 935 side, they find that 0x5D bit 2=1. Could you please tell me what condition will result in CHKSUM_ERR?

In 954 side, the register is as below, could you please help analyze this?

0x4D=0x03 which means that input is locked, and Lock status unchanged;
0x4E=0x0C which means that frequency stable, line length stable, line length unchanged, line count unchanged; CSI Receive error detected. See the CSI_RX_STS register for details
Reading 0x73/74/75/76, line count=720 and line length=2560
0x4F=0x54 and 0x50=0x00, PCLK=(84MHz+0MHz)*2=168MHz  ,this frequency is normal.

0x7A = 0x04 , Data Checksum Error detected for received CSI packet.

Thanks & Best Regards,

Sherry

  • 0
    TI__Mastermind 24810 points

    Hello Sherry,

    Thank you for the detailed information!

    CHKSUM_ERROR is asserted when the 935 detects an error in the check sum portion of the incoming CSI-2 data, the check sum error status is then forwarded to the DES though the BCC, see section 7.3.1.6 of the 935 datasheet. So it is most likely the image sensor or its connection to the SER that is causing the check sum errors.

    Regards,

    Joshua