ADV7280A-M MIPI output abnormal

Dear Specialist,

       We've debugging ADV7280A-M for month. Now we can get MIPI output following the web documents guidance. However, seems the image is mirror or need to be rotated.

Can you advice how to correct the image. Does modify any register can help, or it can only be solved from MCU side. 

Parents Reply
  • Hi,

      But in your shared script seems, you have added one more delay before ADV728x chip reset.

      Please note that As per expert comments "Two 10ms waits are overly conservative.  The first reset can occur as soon as the power rails become stable with a pulse width of ~1ms.  The hardware reset just pushes all the registers to their default state.
    The second software reset needs ~1ms for all registers to return to their default state.
    In reality even 1ms maybe too long, it's just a safe delay to work with.  The second reset probably does not need any delay since the actual reset ripples through faster than the I2C master can write another command.
    If you have a working system I'd experiment by removing the software reset right after the hardware reset and see if the chip operates as expected.  I have not tried this.
    The software reset can be used after power up if the system has no way to drive the hardware reset".

    Thanks,

    Poornima

Children
  •   /* Reset */
      ret = adv7280_write_reg(client,
       ADV7280_POWER_MANAGEMENT, 0x80);//0xA0//check set1
      if (ret < 0){
       SENSOR_ERR("#1#adv7280_reg_init ADV7280_POWER_MANAGEMENT error!");
       goto err_unreg_subdev;
      }
      msleep(10);

    hi

     Do you  mean the soft reset does not need 10ms ?  Thanks !

      

  • Hi,

     Yes, A software reset does not require a time delay. The hardware reset will set all registers to their default state and reset the I2C engine.

     Please note that 5ms reset delay is usually associated with the hardware reset. For hardware reset it is best to keep reset low until the power rails are stable.  Normally this can be accomplished with a simple RC circuit on the reset pin.

    Thanks,

    Poornima