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Last Post 03 Feb 2011 01:50 PM by  richard.laborde@logicpd.com
LCD 6.4 VGA Configuration
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Clintvz



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--
02 Feb 2011 03:32 AM
    I am using the 6.4" VGA display on an L138 EVM with WinCE BSP.

    The BSP supports the 4.3" WQVGA display but not the 6.4" VGA. The Sharp datasheet does not specify the porch parameters as clearly for the LQ64D343 as they do for the LQ043T1DG01. Through trial and error I was able to modify them to get the display reasonbly well centred, but would like to know what the ideal/typical settings should be.

    Below is the default settings for the 4.3", followed by my attempt for the 6.4" version. Does anyone know what changes need to be made for optimal settings? Also if there are any other changes that need to be made to the WinCE environment to make the best use of the 6.4" Display, apart from these changes in the lcd_cfg file?

    //------------------------------------------------------------------------------
    //
    // Sharp LQ043T1DG01 (Logic L-138 WQVGA display kit)
    //
    //
    const orig_LCD_PARAMS LCD_PANEL_PARAMETERS = {
    LCD_SYNCPOL_NEGATIVE, // VSYNC polarity (IVS)
    LCD_SYNCPOL_NEGATIVE, // HSYNC polarity (IHS)
    LCD_PIXELCLKPOL_POSITIVE, // Pixel clock polarity
    LCD_SYNCEDGE_FALLING, // Sync falling edge
    42, // Horizontal Sync Pulse Width (HSW)
    10, // Vertical Sync Pulse Width (VSW)
    485, // Pixel clock periods per line (HFP+PPL+HBP)
    277, // Number of lines per field (VFP+LPP+VBP)
    1, // Horzontal Back Porch (HBP)
    3, // Vertical Back Porch (VBP)
    480, // Horizontal valid data (PPL)
    272, // Vertical valid data (LPP)
    8000000, // Desired LCD pixel clock freq in Hz (8MHz)
    60 // Refresh rate of display in Hz (60Hz)
    };

    //------------------------------------------------------------------------------
    //
    // Sharp LQ64D343 (Logic L-138 VGA display kit)
    //
    //
    const LCD_PARAMS LCD_PANEL_PARAMETERS = {
    LCD_SYNCPOL_NEGATIVE, // VSYNC polarity (IVS)
    LCD_SYNCPOL_NEGATIVE, // HSYNC polarity (IHS)
    LCD_PIXELCLKPOL_POSITIVE, // Pixel clock polarity
    LCD_SYNCEDGE_FALLING, // Sync falling edge
    96, // Horizontal Sync Pulse Width (HSW)
    4, // Vertical Sync Pulse Width (VSW)
    800, // Pixel clock periods per line (HFP+PPL+HBP)
    525, // Number of lines per field (VFP+LPP+VBP)
    160, // Horzontal Back Porch (HBP)
    31, // Vertical Back Porch (VBP)
    640, // Horizontal valid data (PPL)
    480, // Vertical valid data (LPP)
    26000000, // Desired LCD pixel clock freq in Hz (26MHz)
    60 // Refresh rate of display in Hz (60Hz)
    };

    richard.laborde@logicpd.com



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    Posts:247
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    --
    03 Feb 2011 01:50 PM
    Clintvz,

    Here are the settings I have for the 2 screens in question. You may need to modify them slightly for the L138.
    TI had a 3rd party do the WinCE BSP, so all bets are off on how they set up the LCD.

    dev_config->screen[7]: VGA x: 640 y: 480
    DISPC_CONTROL: 0x00018128
    DISPC_SIZE_LCD: 0x01df027f
    DISPC_GFX_SIZE: 0x01df027f
    DISPC_TIMING_H: 0x01908931
    DISPC_TIMING_V: 0x02302002
    DISPC_DIVISOR: 0x00010004
    DISPC_CONFIG: 0x00000000
    DISPC_POL_FREQ: 0x00000000
    CM_CLKSEL_DSS: 0x00001009
    Frame Buffer: 0x80400000

    dev_config->screen[0]: WQVGA x: 480 y: 272
    DISPC_CONTROL: 0x00018128
    DISPC_SIZE_LCD: 0x010f01df
    DISPC_GFX_SIZE: 0x010f01df
    DISPC_TIMING_H: 0x00100229
    DISPC_TIMING_V: 0x0030020a
    DISPC_DIVISOR: 0x0001000b
    DISPC_CONFIG: 0x00000000
    DISPC_POL_FREQ: 0x0000b000
    CM_CLKSEL_DSS: 0x00001009
    Frame Buffer: 0x80400000


    Thanks
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