1 files changed, 326 insertions, 176 deletions

diff --git a/firmware/target/coldfire/iaudio/x5/lcd-x5.c b/firmware/target/coldfire/iaudio/x5/lcd-x5.c
index c06521ef54..2e3e785d73 100755
--- a/firmware/target/coldfire/iaudio/x5/lcd-x5.c
+++ b/firmware/target/coldfire/iaudio/x5/lcd-x5.c
@@ -30,72 +30,59 @@
 #include "font.h"
 #include "bidi.h"
 
-static bool display_on=false; /* is the display turned on? */
+/* Is the display turned on? */
+static bool display_on = false;
 
+/* Amount of vertical offset. Used for offset correction when flipped. */
+static int y_offset = 0;
+
+/* Amount of roll offset (0-127). */
+static int roll_offset = 0;
+
+/* A15(0x8000) && CS1->CS, A1(0x0002)->RS */
 #define LCD_CMD  *(volatile unsigned short *)0xf0008000
 #define LCD_DATA *(volatile unsigned short *)0xf0008002
 
 /* register defines for the Renesas HD66773R */
+#define R_START_OSC             0x00
+#define R_DEVICE_CODE_READ      0x00
+#define R_DRV_OUTPUT_CONTROL    0x01
+#define R_DRV_AC_CONTROL        0x02
+#define R_POWER_CONTROL1        0x03
+#define R_POWER_CONTROL2        0x04
+#define R_ENTRY_MODE            0x05
+#define R_COMPARE_REG           0x06
+#define R_DISP_CONTROL          0x07
+#define R_FRAME_CYCLE_CONTROL   0x0b
+#define R_POWER_CONTROL3        0x0c
+#define R_POWER_CONTROL4        0x0d
+#define R_POWER_CONTROL5        0x0e
+#define R_GATE_SCAN_START_POS   0x0f
+#define R_VERT_SCROLL_CONTROL   0x11
+#define R_1ST_SCR_DRV_POS       0x14
+#define R_2ND_SCR_DRV_POS       0x15
 #define R_HORIZ_RAM_ADDR_POS    0x16
 #define R_VERT_RAM_ADDR_POS     0x17
+#define R_RAM_WRITE_DATA_MASK   0x20
 #define R_RAM_ADDR_SET          0x21
 #define R_WRITE_DATA_2_GRAM     0x22
-
-/*****************************************************
-The table below was generated by the following script:
-
-#!/usr/bin/perl
-
-# high byte table
-print "short high8to9[] = {\n";
-$str = "  ";
-for my $m (0 .. 255) {
-    # RRRRRGGG => RRRRR0GGG
-    my $v = (($m & 0xF8) << 1) | ($m & 0x07);
-    if(length($str) > 75) {
-        print "$str\n";
-        $str="  ";
-    }
-    $str .= sprintf("0x%03x, ", $v);
-}
-print "$str\n};\n";
-
-*****************************************************/
-
-/* Lookup table for 16->18bit conversion, high byte. The low byte is just
-   shifted. */
-const short high8to9[] ICONST_ATTR = {
-  0x000, 0x001, 0x002, 0x003, 0x004, 0x005, 0x006, 0x007, 0x010, 0x011, 0x012,
-  0x013, 0x014, 0x015, 0x016, 0x017, 0x020, 0x021, 0x022, 0x023, 0x024, 0x025,
-  0x026, 0x027, 0x030, 0x031, 0x032, 0x033, 0x034, 0x035, 0x036, 0x037, 0x040,
-  0x041, 0x042, 0x043, 0x044, 0x045, 0x046, 0x047, 0x050, 0x051, 0x052, 0x053,
-  0x054, 0x055, 0x056, 0x057, 0x060, 0x061, 0x062, 0x063, 0x064, 0x065, 0x066,
-  0x067, 0x070, 0x071, 0x072, 0x073, 0x074, 0x075, 0x076, 0x077, 0x080, 0x081,
-  0x082, 0x083, 0x084, 0x085, 0x086, 0x087, 0x090, 0x091, 0x092, 0x093, 0x094,
-  0x095, 0x096, 0x097, 0x0a0, 0x0a1, 0x0a2, 0x0a3, 0x0a4, 0x0a5, 0x0a6, 0x0a7,
-  0x0b0, 0x0b1, 0x0b2, 0x0b3, 0x0b4, 0x0b5, 0x0b6, 0x0b7, 0x0c0, 0x0c1, 0x0c2,
-  0x0c3, 0x0c4, 0x0c5, 0x0c6, 0x0c7, 0x0d0, 0x0d1, 0x0d2, 0x0d3, 0x0d4, 0x0d5,
-  0x0d6, 0x0d7, 0x0e0, 0x0e1, 0x0e2, 0x0e3, 0x0e4, 0x0e5, 0x0e6, 0x0e7, 0x0f0,
-  0x0f1, 0x0f2, 0x0f3, 0x0f4, 0x0f5, 0x0f6, 0x0f7, 0x100, 0x101, 0x102, 0x103,
-  0x104, 0x105, 0x106, 0x107, 0x110, 0x111, 0x112, 0x113, 0x114, 0x115, 0x116,
-  0x117, 0x120, 0x121, 0x122, 0x123, 0x124, 0x125, 0x126, 0x127, 0x130, 0x131,
-  0x132, 0x133, 0x134, 0x135, 0x136, 0x137, 0x140, 0x141, 0x142, 0x143, 0x144,
-  0x145, 0x146, 0x147, 0x150, 0x151, 0x152, 0x153, 0x154, 0x155, 0x156, 0x157,
-  0x160, 0x161, 0x162, 0x163, 0x164, 0x165, 0x166, 0x167, 0x170, 0x171, 0x172,
-  0x173, 0x174, 0x175, 0x176, 0x177, 0x180, 0x181, 0x182, 0x183, 0x184, 0x185,
-  0x186, 0x187, 0x190, 0x191, 0x192, 0x193, 0x194, 0x195, 0x196, 0x197, 0x1a0,
-  0x1a1, 0x1a2, 0x1a3, 0x1a4, 0x1a5, 0x1a6, 0x1a7, 0x1b0, 0x1b1, 0x1b2, 0x1b3,
-  0x1b4, 0x1b5, 0x1b6, 0x1b7, 0x1c0, 0x1c1, 0x1c2, 0x1c3, 0x1c4, 0x1c5, 0x1c6,
-  0x1c7, 0x1d0, 0x1d1, 0x1d2, 0x1d3, 0x1d4, 0x1d5, 0x1d6, 0x1d7, 0x1e0, 0x1e1,
-  0x1e2, 0x1e3, 0x1e4, 0x1e5, 0x1e6, 0x1e7, 0x1f0, 0x1f1, 0x1f2, 0x1f3, 0x1f4,
-  0x1f5, 0x1f6, 0x1f7,
-};
+#define R_RAM_READ_DATA         0x22
+#define R_GAMMA_FINE_ADJ_POS1   0x30
+#define R_GAMMA_FINE_ADJ_POS2   0x31
+#define R_GAMMA_FINE_ADJ_POS3   0x32
+#define R_GAMMA_GRAD_ADJ_POS    0x33
+#define R_GAMMA_FINE_ADJ_NEG1   0x34
+#define R_GAMMA_FINE_ADJ_NEG2   0x35
+#define R_GAMMA_FINE_ADJ_NEG3   0x36
+#define R_GAMMA_GRAD_ADJ_NEG    0x37
+#define R_GAMMA_AMP_ADJ_POS     0x3a
+#define R_GAMMA_AMP_ADJ_NEG     0x3b
 
 /* called very frequently - inline! */
 inline void lcd_write_reg(int reg, int val)
 {
-    LCD_CMD = (reg >> 8) << 1;
-    LCD_CMD = (reg & 0xff) << 1;
+    LCD_CMD = 0x0000; /* MSB is ~always~ 0 */
+    LCD_CMD = reg << 1;
     LCD_DATA = (val >> 8) << 1;
     LCD_DATA = (val & 0xff) << 1;
 }
@@ -103,38 +90,29 @@ inline void lcd_write_reg(int reg, int val)
 /* called very frequently - inline! */
 inline void lcd_begin_write_gram(void)
 {
-    LCD_CMD = (R_WRITE_DATA_2_GRAM >> 8) << 1;
-    LCD_CMD = (R_WRITE_DATA_2_GRAM & 0xff) << 1;
+    LCD_CMD = 0x0000;
+    LCD_CMD = R_WRITE_DATA_2_GRAM << 1;
 }
 
-/* called very frequently - inline! */
-inline void lcd_write_data(const unsigned short* p_bytes, int count) ICODE_ATTR;
-inline void lcd_write_data(const unsigned short* p_bytes, int count)
+static inline void lcd_write_one(unsigned short px)
 {
-    unsigned int tmp;
-    unsigned int *ptr = (unsigned int *)p_bytes;
-    bool extra;
-
-    /* if there's on odd number of pixels, remmber this and output the
-       trailing pixel after the loop */
-    extra = (count&1)?true:false;
-
-    count >>= 1;
-    while(count--) {
-        tmp = *ptr++;
-        LCD_DATA = high8to9[tmp >> 24];
-        LCD_DATA = tmp>>15;
-        LCD_DATA = high8to9[(tmp >> 8)&255];
-        LCD_DATA = tmp<<1;
-    }
-    if(extra) {
-        /* the final "spare" pixel */
-        unsigned short read = *(unsigned short *)ptr;
-        LCD_DATA = high8to9[read >> 8];
-        LCD_DATA = read<<1;
-    }
+    unsigned short pxsr = px >> 8;
+    LCD_DATA = pxsr + (pxsr & 0x1F8);
+    LCD_DATA = px << 1;
 }
 
+/* Write two pixels to gram from a long */
+/* called very frequently - inline! */
+static inline void lcd_write_two(unsigned long px2)
+{
+    unsigned short px2sr = px2 >> 24;
+    LCD_DATA = px2sr + (px2sr & 0x1F8);
+    LCD_DATA = px2 >> 15;
+    px2sr = px2 >> 8;
+    LCD_DATA = px2sr + (px2sr & 0x1F8);
+    LCD_DATA = px2 << 1;
+}
+ 
 /*** hardware configuration ***/
 
 int lcd_default_contrast(void)
@@ -152,18 +130,26 @@ void lcd_set_contrast(int val)
     else if (val > 30)
         val = 30;
 
-    lcd_write_reg(0x0e, 0x2018 + (val << 8));
+    lcd_write_reg(R_POWER_CONTROL5, 0x2018 + (val << 8));
 }
 
 void lcd_set_invert_display(bool yesno)
 {
-    (void)yesno;
+    /* PT1-0=00, VLE2-1=00, SPT=0, GON=1, DTE=1, REV=x, D1-0=11 */
+    lcd_write_reg(R_DISP_CONTROL, yesno ? 0x0033 : 0x0037);
 }
 
 /* turn the display upside down (call lcd_update() afterwards) */
 void lcd_set_flip(bool yesno)
 {
-    (void)yesno;
+    y_offset = yesno ? 4 : 0;
+    /* SCN4-0=000x0 (G160) */
+    lcd_write_reg(R_GATE_SCAN_START_POS, yesno ? 0x0000 : 0x0002);
+    /* SM=0, GS=x, SS=x, NL4-0=10011 (G1-G160)*/
+    lcd_write_reg(R_DRV_OUTPUT_CONTROL, yesno ? 0x0013 : 0x0313);
+    /* Vertical stripe */
+    /* HEA7-0=0xxx, HSA7-0=0xxx */  
+    lcd_write_reg(R_HORIZ_RAM_ADDR_POS, 0x7f00 + (y_offset << 8) + y_offset);
 }
 
 /* Rolls up the lcd display by the specified amount of lines.
@@ -172,19 +158,22 @@ void lcd_set_flip(bool yesno)
  * remapping only and all operations on the lcd are affected.
  * -> 
  * @param int lines - The number of lines that are rolled. 
- *  The value must be 0 <= pixels < LCD_HEIGHT. */
+ *  The value must be 0 <= pixels < LCD_HEIGHT.
+ * Call lcd_update() afterwards */
 void lcd_roll(int lines)
 {
-    (void)lines;
+    /* Just allow any value mod LCD_HEIGHT-1. Assumes LCD_HEIGHT == 128. */
+    if (lines < 0)
+        lines = -lines & 127;
+    else
+        lines = (128 - (lines & 127)) & 127;
+
+    roll_offset = lines;
 }
 
-/* LCD init
- * These settings are taken from the original X5 firmware
- */
+/* LCD init */
 void lcd_init_device(void)
 {
-    display_on=true;
-
     /* LCD Reset */
     and_l(~0x00000010, &GPIO1_OUT);
     or_l(0x00000010, &GPIO1_ENABLE);
@@ -194,60 +183,105 @@ void lcd_init_device(void)
 
     sleep(HZ/100);
 
-    lcd_write_reg(0, 0x0001);
-    
-    sleep(HZ/50);
-    
-    lcd_write_reg(0x0d, 0x0401);
-    lcd_write_reg(0x0e, 0x321e);
-    lcd_write_reg(0x01, 0x0313);
-    lcd_write_reg(0x02, 0x0700);
-    lcd_write_reg(0x05, 0x9038);
-    lcd_write_reg(0x06, 0x0000);
-    lcd_write_reg(0x0b, 0x4000);
-    
-    sleep(HZ/100);
-    
-    lcd_write_reg(0x21,0x0000);
-    lcd_write_reg(0x30,0x0003);
-    lcd_write_reg(0x31,0x0400);
-    lcd_write_reg(0x32,0x0407);
-    lcd_write_reg(0x33,0x0305);
-    lcd_write_reg(0x34,0x0003);
-    lcd_write_reg(0x35,0x0704);
-    lcd_write_reg(0x36,0x0407);
-    lcd_write_reg(0x37,0x0503);
-    lcd_write_reg(0x0f,0x0002);
-    lcd_write_reg(0x11,0x0000);
-    lcd_write_reg(0x14,0x9f00);
-    lcd_write_reg(0x15,0x5c00);
-    lcd_write_reg(0x16,0x7f00);
-    lcd_write_reg(0x17,0x9f00);
-    lcd_write_reg(0x3a,0x1409);
-    lcd_write_reg(0x3b,0x0602);
-    
-    lcd_write_reg(0x0c,0x0001);
+    /** Power ON Sequence **/
+    /* Per datasheet Rev.1.10, Jun.21.2003, p. 99 */
 
+    lcd_write_reg(R_START_OSC, 0x0001); /* Start Oscillation */
+    /* 10ms or more for oscillation circuit to stabilize */
+    sleep(HZ/50);
+    /* Instruction (1) for power setting; VC2-0, VRH3-0, CAD,
+       VRL3-0, VCM4-0, VDV4-0 */
+    /* VC2-0=001 */
+    lcd_write_reg(R_POWER_CONTROL3, 0x0001);
+    /* VRL3-0=0100, PON=0, VRH3-0=0001 */
+    lcd_write_reg(R_POWER_CONTROL4, 0x0401);
+    /* CAD=1 */
+    lcd_write_reg(R_POWER_CONTROL2, 0x8000);
+    /* VCOMG=0, VDV4-0=10011 (19), VCM4-0=11000 */
+    lcd_write_reg(R_POWER_CONTROL5, 0x1318);
+    /* Instruction (2) for power setting; BT2-0, DC2-0, AP2-0 */
+    /* BT2-0=000, DC2-0=001, AP2-0=011, SLP=0, STB=0 */
+    lcd_write_reg(R_POWER_CONTROL1, 0x002c);
+    /* Instruction (3) for power setting; VCOMG = "1" */
+    /* VCOMG=1, VDV4-0=10011 (19), VCM4-0=11000 */
+    lcd_write_reg(R_POWER_CONTROL5, 0x3318);
+
+    /* 40ms or more; time for step-up circuits 1,2 to stabilize */
     sleep(HZ/25);
-    
-    lcd_write_reg(0x03,0x002c);
-    lcd_write_reg(0x04,0x8000);
 
-    sleep(HZ/25);
-    
-    lcd_write_reg(0x0e,0x3318);
+    /* Instruction (4) for power setting; PON = "1" */
+    /* VRL3-0=0100, PON=1, VRH3-0=0001 */
+    lcd_write_reg(R_POWER_CONTROL4, 0x0411);
     
+    /* 40ms or more; time for step-up circuit 4 to stabilize */
     sleep(HZ/25);
-    
-    lcd_write_reg(0x0d,0x0411);
 
-    sleep(HZ/100);
-    
-    lcd_write_reg(0x07,0x0006);
-    lcd_write_reg(0x07,0x036);
-    lcd_write_reg(0x07,0x037);
-    lcd_write_reg(0x07,0x0037);
-    return;
+    /* Instructions for other mode settings (in register order). */    
+    /* SM=0, GS=1, SS=1, NL4-0=10011 (G1-G160)*/
+    lcd_write_reg(R_DRV_OUTPUT_CONTROL, 0x313);
+    /* FLD1-0=01 (1 field), B/C=1, EOR=1 (C-pat), NW5-0=000000 (1 row) */
+    lcd_write_reg(R_DRV_AC_CONTROL, 0x0700);
+    /* DIT=1, BGR=1, HWM=0, I/D1-0=11, AM=1, LG2-0=000 */
+    lcd_write_reg(R_ENTRY_MODE, 0x9038);
+    /* CP15-0=0000000000000000 */
+    lcd_write_reg(R_COMPARE_REG, 0x0000);
+    /* NO1-0=01, SDT1-0=00, EQ1-0=00, DIV1-0=00, RTN3-00000 */
+    lcd_write_reg(R_FRAME_CYCLE_CONTROL, 0x4000);
+    /* SCN4-0=00010 (G160) */
+    lcd_write_reg(R_GATE_SCAN_START_POS, 0x0002);
+    /* VL7-0=0x00 */
+    lcd_write_reg(R_VERT_SCROLL_CONTROL, 0x0000);
+    /* SE17-10(End)=0x9f (159), SS17-10(Start)=0x00 */
+    lcd_write_reg(R_1ST_SCR_DRV_POS, 0x9f00);
+    /* SE27-20(End)=0x5c (92), SS27-20(Start)=0x00 */
+    lcd_write_reg(R_2ND_SCR_DRV_POS, 0x5c00);
+    /* HEA7-0=0x7f, HSA7-0=0x00 */
+    lcd_write_reg(R_HORIZ_RAM_ADDR_POS, 0x7f00); /* Vertical stripe */
+    /* PKP12-10=0x0, PKP02-00=0x0 */
+    lcd_write_reg(R_GAMMA_FINE_ADJ_POS1, 0x0003);
+    /* PKP32-30=0x4, PKP22-20=0x0 */
+    lcd_write_reg(R_GAMMA_FINE_ADJ_POS2, 0x0400);
+    /* PKP52-50=0x4, PKP42-40=0x7 */
+    lcd_write_reg(R_GAMMA_FINE_ADJ_POS3, 0x0407);
+    /* PRP12-10=0x3, PRP02-00=0x5 */
+    lcd_write_reg(R_GAMMA_GRAD_ADJ_POS, 0x0305);
+    /* PKN12-10=0x0, PKN02-00=0x3 */
+    lcd_write_reg(R_GAMMA_FINE_ADJ_NEG1, 0x0003);
+    /* PKN32-30=0x7, PKN22-20=0x4 */
+    lcd_write_reg(R_GAMMA_FINE_ADJ_NEG2, 0x0704);
+    /* PKN52-50=0x4, PRN42-40=0x7 */
+    lcd_write_reg(R_GAMMA_FINE_ADJ_NEG3, 0x0407);
+    /* PRN12-10=0x5, PRN02-00=0x3 */
+    lcd_write_reg(R_GAMMA_GRAD_ADJ_NEG, 0x0503);
+    /* VRP14-10=0x14, VRP03-00=0x09 */
+    lcd_write_reg(R_GAMMA_AMP_ADJ_POS, 0x1409);
+    /* VRN14-00=0x06, VRN03-00=0x02 */
+    lcd_write_reg(R_GAMMA_AMP_ADJ_NEG, 0x0602);
+
+    /* 100ms or more; time for step-up circuits to stabilize */
+    sleep(HZ/10);
+
+    /** Display ON Sequence **/
+    /* Per datasheet Rev.1.10, Jun.21.2003, p. 97 */
+
+    /* PT1-0=00, VLE2-1=00, SPT=0, GON=0, DTE=0, REV=1, D1-0=01 */
+    lcd_write_reg(R_DISP_CONTROL, 0x0005);
+
+    sleep(HZ/25); /* Wait 2 frames or more */
+
+    /* PT1-0=00, VLE2-1=00, SPT=0, GON=1, DTE=0, REV=1, D1-0=01 */
+    lcd_write_reg(R_DISP_CONTROL, 0x0025);
+    /* PT1-0=00, VLE2-1=00, SPT=0, GON=1, DTE=0, REV=1, D1-0=11 */
+    lcd_write_reg(R_DISP_CONTROL, 0x0027);
+
+    sleep(HZ/25); /* Wait 2 frames or more */
+
+    /* PT1-0=00, VLE2-1=00, SPT=0, GON=1, DTE=1, REV=1, D1-0=11 */
+    lcd_write_reg(R_DISP_CONTROL, 0x0037);
+
+    display_on = true;
+    y_offset = 0;
+    roll_offset = 0;
 }
 
 void lcd_enable(bool on)
@@ -274,51 +308,167 @@ void lcd_blit(const fb_data* data, int x, int by, int width,
 
 
 /* Update the display.
-   This must be called after all other LCD functions that change the display. */
+   This must be called after all other LCD functions that change the
+   lcd frame buffer. */
 void lcd_update(void) ICODE_ATTR;
 void lcd_update(void)
 {
-    if(display_on){
-
-        /* Copy display bitmap to hardware */
-        lcd_write_reg(R_RAM_ADDR_SET, 0x0000);
-        lcd_begin_write_gram();
-        lcd_write_data((unsigned short *)lcd_framebuffer, LCD_WIDTH*LCD_HEIGHT);
-    }
-}
+    /* Optimized for full-screen write. */
+    const unsigned long *ptr, *ptr_end;
+
+    if (!display_on)
+        return;
+
+    /* Set start position and window */
+    /* Just add roll offset to start address. CP will roll back around. */
+    lcd_write_reg(R_RAM_ADDR_SET, y_offset + roll_offset); /* X == 0 */
+    lcd_write_reg(R_VERT_RAM_ADDR_POS, (LCD_WIDTH-1) << 8);
+
+    lcd_begin_write_gram();
+
+    ptr = (unsigned long *)lcd_framebuffer;
+    ptr_end = ptr + (LCD_WIDTH*LCD_HEIGHT >> 1);
+
+    do
+    {
+        /* 16 words per turns out to be about optimal according to
+           test_fps. */
+        lcd_write_two(*ptr++);
+#ifndef BOOTLOADER
+        lcd_write_two(*ptr++);
+        lcd_write_two(*ptr++);
+        lcd_write_two(*ptr++);
+        lcd_write_two(*ptr++);
+        lcd_write_two(*ptr++);
+        lcd_write_two(*ptr++);
+        lcd_write_two(*ptr++);
+#endif
+     }
+     while (ptr < ptr_end);
+} /* lcd_update */
 
 /* Update a fraction of the display. */
 void lcd_update_rect(int, int, int, int) ICODE_ATTR;
 void lcd_update_rect(int x, int y, int width, int height)
 {
-    if(display_on) {    
-        int ymax = y + height;
-
-        if(x + width > LCD_WIDTH)
-            width = LCD_WIDTH - x;
-        if (width <= 0)
-            return; /* nothing left to do, 0 is harmful to lcd_write_data() */
-        if(ymax >= LCD_HEIGHT)
-            ymax = LCD_HEIGHT-1;
-
-        /* set update window */ 
-
-        /* horiz ram addr */ 
-        lcd_write_reg(R_HORIZ_RAM_ADDR_POS, (ymax<<8) | y); 
-        
-        /* vert ram addr */ 
-        lcd_write_reg(R_VERT_RAM_ADDR_POS,((x+width-1)<<8) | x); 
-        lcd_write_reg(R_RAM_ADDR_SET, (x<<8) | y); 
-        lcd_begin_write_gram(); 
-
-        /* Copy specified rectangle bitmap to hardware */ 
-        for (; y <= ymax; y++) 
-        { 
-            lcd_write_data ((unsigned short *)&lcd_framebuffer[y][x], width); 
-        } 
-
-        /* reset update window */ 
-        lcd_write_reg(R_HORIZ_RAM_ADDR_POS, 0x7f00);
-        lcd_write_reg(R_VERT_RAM_ADDR_POS, 0x9f00);
+    int y_end;
+    int odd_lead, odd_trail;
+    int duff;
+    const unsigned long *ptr, *duff_end;
+    int stride; /* Actually end of currline -> start of next */
+
+    if (!display_on)
+        return;
+
+    if (x + width > LCD_WIDTH)
+        width = LCD_WIDTH - x; /* Clip right */
+    if (x < 0)
+        width += x, x = 0; /* Clip left */
+    if (width <= 0)
+        return; /* nothing left to do */
+
+    y_end = y + height;
+    if (y_end > LCD_HEIGHT)
+        y_end = LCD_HEIGHT; /* Clip bottom */
+    if (y < 0)
+        y = 0; /* Clip top */
+    if (y >= y_end)
+        return; /* nothing left to do */
+
+    ptr = (unsigned long *)&lcd_framebuffer[y][x];
+
+    /* Set start position and window */
+    lcd_write_reg(R_RAM_ADDR_SET, (x << 8) |
+        (((y + roll_offset) & 127) + y_offset));
+    lcd_write_reg(R_VERT_RAM_ADDR_POS, ((x + width - 1) << 8) | x);
+
+    lcd_begin_write_gram();
+
+    /* Aligning source reads to long boundaries helps 2% - 3% with IRAM
+       buffer. DK with DRAM. */
+
+    /* special case widths 1 and 2. */
+    switch (width)
+    {
+    case 1:
+        odd_lead = 1; /* odd_lead case writes pixels */
+        odd_trail = 0;
+        duff = 0; /* Squelch compiler warning. */
+        duff_end = ptr;
+        break;
+    case 2: /* Just read as long */
+        odd_lead = 0;
+        odd_trail = 0;
+        duff = 1;
+        duff_end = ptr + 1;
+        break;
+    default:
+        odd_lead = x & 1;
+
+        if (odd_lead)
+        {
+            duff = width - 1;
+            odd_trail = duff & 1;
+            duff >>= 1;
+        }
+        else
+        {
+            duff = width >> 1;
+            odd_trail = width & 1;
+        }
+
+        duff_end = ptr + duff;
+#ifndef BOOTLOADER        
+        duff &= 7;
+#endif
+    } /* end switch */
+
+    stride = LCD_WIDTH - width + odd_trail; /* See odd_trail below */
+
+    do
+    {
+        if (odd_lead)
+        {
+            /* Write odd start pixel. */
+            lcd_write_one(*(unsigned short *)ptr);
+            ptr = (unsigned long *)((short *)ptr + 1);
+        }
+
+        if (ptr < duff_end)
+        {
+#ifdef BOOTLOADER
+            do
+                lcd_write_two(*ptr);
+            while (++ptr < duff_end);
+#else           
+            switch (duff)
+            {
+            do
+            {
+                case 0: lcd_write_two(*ptr++);
+                case 7: lcd_write_two(*ptr++);
+                case 6: lcd_write_two(*ptr++);
+                case 5: lcd_write_two(*ptr++);
+                case 4: lcd_write_two(*ptr++);
+                case 3: lcd_write_two(*ptr++);
+                case 2: lcd_write_two(*ptr++);
+                case 1: lcd_write_two(*ptr++);
+            }
+            while (ptr < duff_end);
+            } /* end switch */
+#endif /* BOOTLOADER */
+
+            duff_end += LCD_WIDTH/2;
+        }
+
+        if (odd_trail)
+        {
+            /* Finish remaining odd pixel. */
+            lcd_write_one(*(unsigned short *)ptr);
+            /* Stride increased by one pixel. */
+        }
+
+        ptr = (unsigned long *)((short *)ptr + stride);
     }
+    while (++y < y_end);
 }