Graph Widget causing whitish LCD

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  • Graph Widget causing whitish LCD

    Hi,

    I am using 320 x 240 LCD display with LPC1788 custom board.
    CPU clock is 120Mhz

    SDRAM configuration is 60Mhz used for LCD buffer

    LCD clock is 6400000 Hz

    RGB mode is 565
    LCD multi buffering is enabled

    Everything runs fine till graph widget is included in the window.the window contains only text widget and graph widget.

    When graph widget is included using the graph create indirect function and when the window is displayed the LCD goes whitish. I can see the other text on LCD but it becomes totally whitish like the contrast has become very high. I have still passed any data to graph widget.

    This occurs as soon as screen is shown with graph widget. when i remove the graph widget then the window displays correctly.
    I played around the LCD clock which is controlled by LCD engine of LPC1788. I observed that when LCD clock is reduced to half i.e. 3200000 Hz the graph is displayed correctly.

    why the whitish lcd is coming in the first place with 6400000 Hz and why does the problem go with 3200000 Hz.
    As the LCD clock is reduced the graph is working but LCD starts to flicker a bit. So i have to run the graph with higher frequency only.

    What else can be done so that the LCD does not flicker and also LCD displays correctly with graph included

    Thanks in advance

    Anuj