TQ2440 Study Notes—— 25. LCD Controller

         * The frame memory is completely consistent with the viewpoint,

         * The image data format is as follows (at 8BPP, the data in the frame buffer is the index value in the palette):

         *         |----PAGEWIDTH----|

         * y/x 0 1 2 639

         *     0   idx idx idx ... idx

         *     1   idx idx idx ... idx

         * 1. LCDSADDR1:

         * Set LCDBANK, LCDBASEU

         * 2. LCDSADDR2:

         * Set LCDBASEL: frame buffer end address A[21:1]

         * 3. LCDSADDR3:

         * OFFSIZE is equal to 0, PAGEWIDTH is equal to (640/2)

         */

        LCDSADDR1 = ((LCDFRAMEBUFFER>>22)<<21) | LOWER21BITS(LCDFRAMEBUFFER>>1);

        LCDSADDR2 = LOWER21BITS((LCDFRAMEBUFFER+

                    (LINEVAL_TFT_640480+1)*(HOZVAL_TFT_640480+1)*1)>>1);

        LCDSADDR3 = (0<<11) | (LCD_XSIZE_TFT_640480/2);

        /* Disable temporary palette register */

        TPAL = 0;

        fb_base_addr = LCDFRAMEBUFFER;

        bpp = 8;

        xsize = 640;

        ysize = 480;

        break;

    case MODE_TFT_16BIT_640480:

        /* 

         * Set the LCD controller's control registers LCDCON1~5

         * 1. LCDCON1:

         * Set the frequency of VCLK: VCLK(Hz) = HCLK/[(CLKVAL+1)x2]

         * Select LCD type: TFT LCD   

         * Set display mode: 16BPP

         * Disable LCD signal output first

         * 2. LCDCON2/3/4:

         * Set the time parameters of the control signal

         * Set the resolution, i.e. the number of rows and columns

         * Now, the display frequency can be calculated according to the formula:

         * When HCLK=100MHz,

         * Frame Rate = 1/[{(VSPW+1)+(VBPD+1)+(LIINEVAL+1)+(VFPD+1)}x

         *              {(HSPW+1)+(HBPD+1)+(HFPD+1)+(HOZVAL+1)}x

         * {2x(CLKVAL+1)/(HCLK)}]

         *            = 60Hz

         * 3. LCDCON5:

         * Data format when setting display mode to 16BPP: 5:6:5

         * Set the polarity of HSYNC and VSYNC pulses (this needs to refer to the specific LCD interface signal): Invert

         * Halfword (2-byte) swap enable

         */

        LCDCON1 = (CLKVAL_TFT_640480<<8) | (LCDTYPE_TFT<<5) |

                  (BPPMODE_16BPP<<1) | (ENVID_DISABLE<<0);

        LCDCON2 = (VBPD_640480<<24) | (LINEVAL_TFT_640480<<14) |

                  (VFPD_640480<<6) | (VSPW_640480);

        LCDCON3 = (HBPD_640480<<19) | (HOZVAL_TFT_640480<<8) | (HFPD_640480);

        LCDCON4 = HSPW_640480;

        LCDCON5 = (FORMAT8BPP_565<<11) | (HSYNC_INV<<9) | (VSYNC_INV<<8) |

                  (HWSWP<<1);

        /*

         * Set the LCD controller address register LCDSADDR1~3

         * The frame memory is completely consistent with the viewpoint,

         * The image data format is as follows:

         *         |----PAGEWIDTH----|

         * y/x 0 1 2 639

         *     0   rgb rgb rgb ... rgb

         *     1   rgb rgb rgb ... rgb

         * 1. LCDSADDR1:

         * Set LCDBANK, LCDBASEU

         * 2. LCDSADDR2:

         * Set LCDBASEL: frame buffer end address A[21:1]

         * 3. LCDSADDR3:

         * OFFSIZE is equal to 0, PAGEWIDTH is equal to (640*2/2)

         */

        LCDSADDR1 = ((LCDFRAMEBUFFER>>22)<<21) | LOWER21BITS(LCDFRAMEBUFFER>>1);

        LCDSADDR2 = LOWER21BITS((LCDFRAMEBUFFER+

                    (LINEVAL_TFT_640480+1)*(HOZVAL_TFT_640480+1)*2)>>1);

        LCDSADDR3 = (0<<11) | (LCD_XSIZE_TFT_640480*2/2);

        /* Disable temporary palette register */

        TPAL = 0;

        fb_base_addr = LCDFRAMEBUFFER;

        bpp = 16;

        xsize = 640;

        ysize = 480;

        break;

    default:

        break;

    }   

}

/*

 * Set the color palette

 */

void Lcd_Palette8Bit_Init(void)

{

    int i;  

    volatile unsigned int *palette;

LCDCON1 &= ~0x01; // stop lcd controller

    LCDCON5 |= (FORMAT8BPP_565<<11); // Set the data format in the palette to 5:6:5

    palette = (volatile unsigned int *)PALETTE;

    for (i = 0; i < 256; i++)

        *palette++ = DEMO256pal[i];

LCDCON1 |= 0x01; // re-enable lcd controller

}

/*

 * Change the palette to a single color

 * Input parameters:

 * color: color value, format is 0xRRGGBB

 */

void ChangePalette(UINT32 color)

{

    int i;

    unsigned char red, green, blue;

    UINT32 *palette;

red   = (color >> 19) & 0x1f;

green = (color >> 10) & 0x3f;

blue  = (color >>  3) & 0x1f;

color = (red << 11) | (green << 5) | blue; // 格式5:6:5

    palette=(UINT32 *)PALETTE;

LCDCON1 &= ~0x01; // stop lcd controller

    for (i = 0; i < 256; i++)

    {

// while (((LCDCON5>>15) & 0x3) == 2); // Wait until VSTATUS is not "valid"

        *palette++ = color;

    }

LCDCON1 |= 0x01; // re-enable lcd controller

}

/*

 * Set whether to output LCD power switch signal LCD_PWREN

 * Input parameters:

 * invpwren: 0 - Normal polarity when LCD_PWREN is valid

 * 1 - Invert polarity when LCD_PWREN is active

 * pwren: 0 - LCD_PWREN output is valid

 * 1 - LCD_PWREN output is disabled

 */

void Lcd_PowerEnable(int invpwren, int pwren)

{

    GPGCON = (GPGCON & (~(3<<8))) | (3<<8);   // GPG4用作LCD_PWREN

    GPGUP = (GPGUP & (~(1<<4))) | (1<<4); // Disable internal pull-up    

    LCDCON5 = (LCDCON5 & (~(1<<5))) | (invpwren<<5); // Set LCD_PWREN polarity: normal/inverted

    LCDCON5 = (LCDCON5 & (~(1<<3))) | (pwren<<3); // Set whether to output LCD_PWREN

}    

/*

 * Set whether the LCD controller outputs a signal

 * Input parameters:

 * onoff: 

 * 0 : Disable

 * 1 : Open

 */

void Lcd_EnvidOnOff(int onoff)

{

    if (onoff == 1)

    {

        LCDCON1 |= 1;         // ENVID ON

    }

    else

    {

        LCDCON1 &= 0x3fffe;  // ENVID Off

    }

}    

/*

 * Output monochrome images using temporary palette registers

 * Input parameters:

 * color: color value, format is 0xRRGGBB

 */

void ClearScrWithTmpPlt(UINT32 color)

{

    TPAL = (1<<24)|((color & 0xffffff)<<0);

}

/*

 * Stop using temporary palette registers

 */

void DisableTmpPlt(void)

{

    TPAL = 0;

}

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