LCD connection issue

Hi Vineet,

I recommend you to use the DSS for data transfer to LCD. I think should be useful to read the following article about LCD connectivity:

http://processors.wiki.ti.com/index.php/LCD_connectivity

After connect your display is very possible discover that it is not supported by the software because there is no suitable driver. If this happens I suggest you to look at the specifications of the AT070TN83 display panel and modify the generic panel driver ../kernel/drivers/video/omap2/displays/panel-generic.c as described below:

 /* Innolux AT070TN83 */
    {
        {
            .x_res        = 800,
            .y_res        = 480,
            .pixel_clock    = 40000,
            .hsw        = 45,
            .hfp        = 1,
            .hbp        = 1,
            .vsw        = 3,
            .vfp        = 12,
            .vbp        = 20,
        },
        .acbi            = 0x0,
        .acb            = 0x28,
        .config            = OMAP_DSS_LCD_TFT | OMAP_DSS_LCD_IVS | OMAP_DSS_LCD_IHS,
        .power_on_delay        = 0,
        .power_off_delay    = 0,
        .name            = "innolux_at070tn83",
    },

Then you should add used mode definition to the ../kernel/drivers/video/modedb.c something link:

    {
       /* 800x480 @ 60 Hz, AT070TN83 LCD */
       NULL, 60, 800, 480, KHZ2PICOS(3000), 40, 40, 13, 29, 48, 3,
       0, FB_VMODE_NONINTERLACED
    },

BR

Tsvetolin Shulev

Hii Cvetolin

Thanks for your quick reply.

What you instructed i have done means kernel i have compiled.

but now how to check whether lcd is working or not..?

i am not much familiar with linux programming.

how to write an app to test lcd working.?

and while booting from microsd card setenv bootargs is there

setenv bootargs console=ttyO2,115200n8 rw rootwait rootfstype=ext3 rootdelay=1 root=/dev/mmcblk0p2 mpurate=1000

and while searching i got this for andriod

setenv bootargs 'console=ttyO2,115200n8 androidboot.console=ttyO2 mem=256M root=/dev/mmcblk0p2 rw rootfstype=ext3 rootwait init=/init ip=off omap_vout.vid1_static_vrfb_alloc=y vram=8M omapfb.vram=0:8M omapdss.def_disp=dvi omapfb.mode=dvi:1024x768-16'

so here related to display arguments are there..

So can you please add something same realted to linux booting process.

Regards

Vineet

Hi Vineet,

I'm not able to see the whole configuration of yours bootargs because the row cut but I recommend you to use bootargs settings of my board:

setenv bootargs 'console=ttyO0,115200n8 root=/dev/mmcblk0p2 rw ip=off mem=55M@0x80000000 mpurate=1000  omap_vout.vid1_static_vrfb_alloc=y omapfb.vram=0:4M mem=128M@0x88000000 rootwait'

BR

Tsvetolin Shulev

Hi,

i am trying to draw a box on screen but its coming small and four same box .

it like

------------------------------------------------------------------------

|''''''''''''''''|         |''''''''''''''''|        |''''''''''''''''|          |''''''''''''''''|

|............|         |............|        |............|          |............|

---------------------------------------------------------------------------

whether its problem in buffer writing or what.?

regards,

vineet

Hi Vineet,

The console output strongly depends on the console terminal client application. You should ensure that your console using monospace (fixed-width) font. Also you should check buffer writing and should bu good to flash the buffer.

BR

Tsvetolin Shulev

Hi Tsvetolin,

Thanx for you reply, But still i am not getting the excat output.

Can you tell me how to write to buffer.?

I m writing the data to GFX_BA0 = 0x80500000  base address.

Can you help by giving a test app.?

Regards,

Vineet

HI,

I am trying to write directly to the buffer to get the some colored patterns,

but i m not getting.. i m writing to the base address,some color values but its not reflecting back to the lcd.

base address 0x80500000..

BR

vineet

Hi Vineet,

Writing directly to the buffer is possible but not sure method for drawing on the lcd. You must ensure that you are the only which writing to the buffer (no one function no writing at this moment to the buffer). Therefore you could read the sequence of data which you are writing after some period of time (1 - 2 seconds for example) and compare with date which you expect to be there.

BR

Tsvetolin Shulev

Hi Cvetolin,

Now i m just testing the setting, so only one function writing to the buffer.

But still i am not getting the expected output.

BR

vineet

Hi,

Can any one help me displaying fonts on lcd..?

character set for lcd panel(800*480).

Any site to refer how to do it..?

BR

Vineet