When DVD is playing getting some white dotted lines at top of the scree

Satish,

The dashed line is closed caption VBI data that is carried on line 21.  Do you have a way to crop this line in the processor or vertically shift the display so it is not visible.  This line is typically cropped in the back-end and not by the TVP, since some processors need to process the data that is own this line.

You are using embedded syncs, right?   Registers 11h-12h control horizontal horizontal position of AVID signal and the horizontal position of the EAV/SAV embedded sync codes. VBLNK settings control the vertical postion and duration of the AVID signal but do not alter the position of the embedded sync V-bit.  The embedded sync vertical position cannot be changed by a direct I2C resgister and is more difficult to control.  It is best to control this in the back-end processor.

Hello Larry Taylor,

Thanks alot for the replay.We will try to cropp that unwanted dotten lines from back-end process.But we need some information how to set the VBLK(18h, 19h) registers.If you have any information how to set these regsiter values please share it with us.From the data sheet not getting complete inforamtion clearly.We tried setting those (18h-19h) registers , but we are geeting some extra lines on the screen.

Thanks and Regards,

Satish

The VBLK Start/Stop registers affect the VBLK interval of the AVID output signal (pin26).  Increasing VBLK Stop (REG19h) by 1 should move the first line from the active portion of the AVID output signal.  For this to be effective at removing the line, the processor must use the AVID output signal to qualify active video.  The video lines to do not automatically get forced to black level during the VBLK interval.

Hello Larry Taylor,

From your answer to one of post to shift the vertical position i got the below information.

*************************************************************************************************

Larry

// First unlock the TVP5150AM1 for this update

Set REG 0x21 = 0x51

Set REG 0x22 = 0x50

Set REG 0x23 = 0xFF

SEt REG 0x24 = 0x04

//Now modify the v-bit start register,

Set REG 0x21 = 0x00 // Data MSB

Set REG 0x22 = 0x04  // Data LSB

Set REG 0x23 = 0x2B  //register address

SEt REG 0x24 = 0x04  //register bank

//and v-bit stop register

Set REG 0x21 = 0x00 //register data MSB

Set REG 0x22 = 0x03 //register data LSB

Set REG 0x23 = 0x2C //register address

SEt REG 0x24 = 0x04 //register bank

********************************************************************************************************

I have modifed the above code.Please see the below for the same.

Larry

// First unlock the TVP5150AM1 for this update

Set REG 0x21 = 0x51

Set REG 0x22 = 0x50

Set REG 0x23 = 0xFF

SEt REG 0x24 = 0x04

//Now modify the v-bit start register,

Set REG 0x21 = 0x00 // Data MSB

Set REG 0x22 = 0x09  // Data LSB

Set REG 0x23 = 0x2B  //register address

SEt REG 0x24 = 0x04  //register bank

//and v-bit stop register

Set REG 0x21 = 0x00 //register data MSB

Set REG 0x22 = 0x08 //register data LSB

Set REG 0x23 = 0x2C //register address

SEt REG 0x24 = 0x04 //register bank

With above changes the unwanted dotted lines are shifting below.That means the screen is shifting below.But i need the screen shold move up.Can you please suggest me possible register values to move the screen UP.

Thanks and Regards,

Satish

Hello Larry Taylor,

Can you please let me know to shift the video up(vertical size increase) by changing the above register values.If  you have any document for doing these calculations please share with us or tell us how to do calculations for setting these register values.Waiting for your replay.Please help us in this problem.

Thanks and Regards,

Satish

Hello Larry Taylor,

I was waiting for your replay.Can you please give some idea how to set those register values or give some information on those registers.Also please suggest different back-end methods to remove those unwanted lines.

Thanks and Regards,

Satish