NTSC output for APALIS IMX6

[morelmathias]

Hi,

I contact you because i have read your post here :

https://community.nxp.com/message/442000?commentID=442000#comment-442000 

You seem to be good in display parameters.

I have an Apalis card and i want an NTSC/PAL output. For beggining i test only the NTSC.

So I want to use the AD723 chip which use the vga output.

I patch my linux kernel with the patch 0001 and 0004 from here :

Patch for iMX6 BSP to support interlaced display on HDMI and LCD interface 

And i modify the file :

nano ~/linux-toradex/drivers/video/fbdev/mxc/mxc_vdacif.c

by adding these parameters :

  /*NTSC */

        { NULL, 30, 720, 487, 74074, 16, 2, 17, 3, 142, 1,

          FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,

          FB_VMODE_INTERLACED, FB_MODE_IS_DETAILED },

};

That's your parameters for BT1120.

I have the video on my display but it's like the video always scrolling.

The AD723 need RS170A timing that i found here :

http://atarionline.pl/forum/?PostBackAction=Download&AttachmentID=6601 

and p8 of

https://www.matrox.com/imaging/media/pdf/support/cameras/camera_guide.pdf 

Can you explain me or give me the correct configuration?

Here the result with the configuration :

https://youtu.be/T45yGvkcr8g

[Bio_TICFSL]

(y)

[qiang_li-mpu_se]

Hi morel mathias, I checked the ad723 datasheet, its input is analog VGA signal, but the output from IMX6 is digital RGB signals. They are not the same thing.

[morelmathias]

Hi Qiang_FSL,

I have the imx6 on the Apalis board :

Apalis iMX6 Quad 2GB IT  | V1.1C

This card have a VGA output.

[qiang_li-mpu_se]

The "Patch for iMX6 BSP to support interlaced display on HDMI and LCD interface" can't output standard NTSC data (different lines in odd and even fields).

What you can tried is followed:

      { NULL, 30, 720, 480, 74074, 114, 38, 31, 8, 124, 6,
          0,
          FB_VMODE_INTERLACED, 0 },

[morelmathias]

For information,

the best configuration i found is this one :

        /* 3 640x480-60 VESA */

        { NULL, 60, 640, 480,  79364,  48, 16, 33, 10, 96, 2,

          FB_SYNC_OE_LOW_ACT, FB_VMODE_INTERLACED, FB_MODE_IS_VESA },

Monitor display 480/60I

Fbset return

mode "640x480-60"

    # D: 12.600 MHz, H: 15.750 kHz, V: 60.001 Hz

    geometry 640 480 640 480 16

    timings 79364 48 16 33 10 96 2

    laced true

    rgba 5/11,6/5,5/0,0/0

endmode

[qiang_li-mpu_se]

I think the fbset doesn't support the 720*480i resolution, you can reference to https://community.nxp.com/docs/DOC-100657 to let the kernel boot in that mode directly.

Use the mxc_lcdif.c driver with kernel command line: video=mxcfb0:dev=lcd,LCD-NTSC,if=RGB565

[morelmathias]

Hi,

I only use the fbset to read my parameter configure with the kernel command line.

That show me the pixel clock, the Hsync and Vsync too.

One problem is that now I do not have the output on the LCD but on the vga.

[morelmathias]

Hi,

Thank you for the response.

The given configuration doesn't work, no video at all.

Fbset return :
mode "720x480-52"
# 13.500 MHz, H: 13.554 kHz, V: 51.635 Hz
geometry 720 480 720 480 16
timings 74074 114 38 31 8 124 6
hsync high
vsync high
laced true
rgba 5/11,6/5,5/0,0/0
endmode

could you explain why you use UNKNOWN mode?

#define FB_MODE_IS_UNKNOWN     0#define FB_MODE_IS_DETAILED     1#define FB_MODE_IS_STANDARD     2#define FB_MODE_IS_VESA          4