VGA YPbPr Ghost Image

Ri-Ping YU

Expert 1460 points

Hi, TIers

I'm using DM8168 with RDK 3.0

There is ghost image in my VGA/YPbPr output, issue and my privious attempting are described in

http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/717/p/302687/1060719.aspx#1060719

Now, I have one evaluation board from TI's 3rd party, its YPbPr output works properly,

so , I compared values of 53 HDVPSS-HD-VENC registers between them, and I noticed the disparity just in one register(with address 0x48108048), the value of our board is 0x05003000, the 3rd party's is 0x05004000,

According to the NDA datasheet

"DigitalMediaProcessors High-DefinitionVideoProcessingSubsystem(HDVPSS)TechnicalReferenceManual"

it means the starting location of the VS pulse in a frame, ours' is 0x03, the other board is 0x04;

I don't know the exact meaning of these values,

and I want to replace the value of the register on our board with the other's to do a try, how can I do this?

Appreciate with any reply!

over 12 years ago

0 Renjith Thomas over 12 years ago

Guru 31670 points

YU,

You can modify the value at run time by using devmem or devmem2 command.

0 Brijesh Jadav over 12 years ago in reply to Renjith Thomas

TI__Guru**** 487505 points

First enable internal color bar and see if it is correct. if it is correct, it is not vsync start issue.

Regards,

Brijesh

0 Ri-Ping YU over 12 years ago in reply to Brijesh Jadav

Expert 1460 points

Thanks Brijesh!

I don't know how to enable internal color bar, looking forward to your furthur suggestion.

Regards

0 Ri-Ping YU over 12 years ago in reply to Brijesh Jadav

Expert 1460 points

./dvr_rdk/mcfw/src_bios6/links_m3vpss/system/system_m3vpss.c

Int32 System_platformSelectHdCompSyncSrc(System_HdCompSyncSource syncSrc,
UInt32 enable)

is related to VGA display, but I found there is no function calling it , how does it work?

Regards!

0 Brijesh Jadav over 12 years ago in reply to Ri-Ping YU

TI__Guru**** 487505 points

Yes, it is , This api is used to select the pins to be used for the hsync/vsync output of VGA. Please configure it appropriately.

To enable internal color bar, set bit 15 of 0x48108000 offset.

Regards,

Brijesh

0 Ri-Ping YU over 12 years ago in reply to Brijesh Jadav

Expert 1460 points

what I confused is that

./dvr_rdk/mcfw/src_bios6/links_m3vpss/system/system_m3vpss.c

Int32 System_platformSelectHdCompSyncSrc(System_HdCompSyncSource syncSrc,
UInt32 enable)

has not been invoked by any function, it seems that the function has no effect on the usecase.

Regards!

0 Ri-Ping YU over 12 years ago in reply to Ri-Ping YU

Expert 1460 points

./mem_rdwr.out --wr 0x48108000 0x440320B3

Is this correct? I do so, but it does not effect, I can not see internal color bar...

Regards!

0 Ri-Ping YU over 12 years ago in reply to Ri-Ping YU

Expert 1460 points

Hi, Brijesh

Thanks for your suggestion

I've generated the inner color bar in 8168 for HDCOMP, there is no ghostimage as shown

But I noticed that if blank windows displayed on HDCOMP, ghostimage cannot be seen also...

What does this mean?

Expecting your further suggestion

Best Regards!

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VGA YPbPr Ghost Image