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Demos appear Magenta on the Display

Other Parts Discussed in Thread: THS8200, THS7353, TVP5147, TVP7002, THS7303

Hi everyone,

I'm developing on the DVEVM dm6467t evaluation board, and I have some problems

with the demos: they display the colors turned to Magenta.

 

I  capture SD signal with the capture demo, record it into a file, and play it with

the decode demo.

 

There's only one little problem: I feed the component output from the board

to a sony professional monitor, and the clips - wether they are displayed from the capture

feedback monitor or from the encode demo - appear with colors turned to magenta.

I have struggled with all the monitor configurations, and double-checked the 

connection of the component bnc's, but nothing changed.

Do you know if there's any trick that I could be missing?

 

Here is the hardware and software set configuration:

- J13 connector of the dvevm dm6467t board feeded with composite signal from a SD PAL interlaced @50Hz videoclip.

- The display is a Sony PVM-14M4E.

- The capture.c code has been tweaked:

--The capture connection settings for the driver is forced by code by placing the line

cAttrs.videoInput = Capture_Input_COMPOSITE;

after all variable initialization code within capture.c.

-- To enable the autodetection of the videoStd, I placed the call:

Capture_detectVideoStd(hCapture, &videoStd, &cAttrs);  

between the previously described line and the functions in charge of doing

all the buffer size and dimension calculations. This way, the code will

use correct videoStd information to calculate the buffers' size and dimensions.

-- I've Commented out the following code:

    /* We only support 720P capture */
//    if (videoStd != VideoStd_720P_50 && videoStd != VideoStd_720P_60) {
//        ERR("Need 720P composite input to this demo\n");
//        cleanup(THREAD_FAILURE);
//    }

which was responsible to kick off the program if it encountered other video standards than

720P @50 and 720P @60.

 

I must say that, even the demos supplied in the board's hard disk that load by default if

the board boots from flash and local hard disk, display all videos in Magenta.

 

Can It be a hardware problem with the ths8200 ?

 

I'll wait your response very eagerly. Thanks!

  • Hello,

    The wiring of THS7353 has changed between EVM RevC and previous revisions. It may be that the issue you are facing is because of this change.

    Can you please ensure your kernel configuration is in accordance with the documentation here:

    http://processors.wiki.ti.com/index.php/DaVinci_PSP_03.02_Linux_Installation_User_Guide#Change_in_Video_capture_between_DM6467T_EVM_Rev_C_and_earlier_revisions

    Thanks,

    Sekhar

  • Hi Sekhar,

    I've applied your advice, but nothing changed.

    I've been browsing through the board documentation, and I've found the following points:

    - It seems that the ths7353 chip is responsible for the amplification of the signal captured through the component input ports (connectors J1, J2 and J3).

    The fact that the configuration of the ths7353 could be wrong, doesn't change my scenario, because I'm doing the capture through the composite connector (J13, capturing

    throught the TVP5147).

    Another fact is that although all of the demos supplied within the hard disk of the board show magenta too.

    What is relevant is that the decode demo shows magenta even if I use the video sequences supplied (that is video sequences that have not been captured through the ths7353 + tvp7002 port).

     

    I think that the problem can be related with the ths7303, which amplifies the output components signal (which is supplied to it by the ths8200 DAC). But here I can do little,

    because the kernel drivers for ths7303 doesn't have options to tweak.

     

    At this point, I can see three possibilities:

    1- The kernel drivers are wrong.

    2- The chip ths7303 is wrong.

    3- Something else that I can't figure out.

     

    Thanks for the advice, anyway!!