WinCE的LCD驱动程序编写指南本文以1024*768分辨率的TFT_16BPP真彩LCD为例,说明在WIN CE 4.2中驱动程序的修改事项，目标板的微处理器是S3C2410A。
该LCD的时序图如下图所示：
Note：LCD时序的参数和时钟相位因不同LCD而异,请参考相应LCD的datasheet.
在WIN CE 4.2中修改LCD驱动程序有五个相关文件,分别是：
1. …/WINCE420/PLATFORM/SMDK2410/INC/s2410.h
2. …/WINCE420/PLATFORM/SMDK2410/KERNEL/HAL/cfw.c
3. …/WINCE420/PLATFORM/SMDK2410/DRIVERS/DISPLAY/S3C2410LCD/s3c2410disp.cpp
4. …/WINCE420/PLATFORM/SMDK2410/FILES/config.bib
5. …/ WINCE420/PLATFORM/SMDK2410/FILES/platform.reg
1. s2410.h
…/WINCE420/PLATFORM/SMDK2410/INC/s2410.h
主要有LCD控制器的寄存器定义、LCD控制器的工作时序定义、分辨率的定义等等。红色部分为修改后的内容：
#define LCDTYPE TFT16BPP
#define LCD_TYPE TFTxxx_xxx
#define SCR_XSIZE_TFT (1280)
#define SCR_YSIZE_TFT (960)
#define LCD_XSIZE_TFT (1024)
#define LCD_YSIZE_TFT (768)
#define VBPD ((2-1)&0xff)
#define VFPD ((2-1)&0xff)
#define VSPW ((2-1) &0x3f)
#define HBPD ((16-1)&0x7f)
#define HFPD ((200-1)&0xff)
#define HSPW ((16-1)&0xff)
#define CLKVAL_TFT (1) //这个值的定义在LCD初始化函数中并不用到,而是直接用数值表示。
2. cfw.c
…/WINCE420/PLATFORM/SMDK2410/KERNEL/HAL/cfw.c
红色部分为修改后的内容：
static void InitDisplay()
{
********
s2410LCD->rLCDCON1=(1<<8)|(MVAL_USED<<7)|(3<<5)|(12<<1)|0;
// CLKVAL_TFT = 1 , HCLK = 100MHz -> VCLK = 25MHz
//TFT LCD panel
//16 bpp for TFT
s2410LCD->rLCDCON2=(VBPD<<24)|(LINEVAL_TFT<<14)|(VFPD<<6)|(VSPW);
s2410LCD->rLCDCON3=(HBPD<<19)|(HOZVAL_TFT<<8)|(HFPD);
s2410LCD->rLCDCON4=(MVAL<<8)|(HSPW);
s2410LCD->rLCDCON5=
(1<<11)|(0<<10)|(0<<9)|(0<<8)|(0<<7)|(0<<6)|(0<<3)|(0<<1)|(1<<0);
//5:6:5 Format
//The video data is fetched at VCLK falling edge
//VLINE/HSYNC pulse polarity-Normal
//VFRAME/VSYNC pulse polarity-Normal
//VD (video data) pulse polarity-Normal
//VDEN signal polarity-Normal
//Disable PWREN signal
//Byte swap Disable
//Half-Word swap Enable
********
}
红色部分为修改后的内容：
WORD TempBuffer[1025][768];
S3C2410DISP::S3C2410DISP (void)
{
********
m_nScreenWidth = 1024;
m_nScreenHeight = 768;
*********
}
到此修改工作基本完成，但还要一个问题：1024*768分辨率占用的显示缓冲区大小是：1024*768*2 = 1536 K Bytes,因此要确认所分配的内存空间够不够,是在config.bib文件中定义的。如果以前定义的足够大,后面的步骤可以省略了。
4. config.bib
…/WINCE420/PLATFORM/SMDK2410/FILES/config.bib
#define NKNAME NK
#define NKSTART 8C200000
#define NKLEN 01D00000
#define RAMSTART 8E000000
#define RAMLEN 01F00000
$(NKNAME) $(NKSTART) $(NKLEN) RAMIMAGE
RAM $(RAMSTART) $(RAMLEN) RAM
AUD_DMA 8c002000 00002000 RESERVED
DRV_GLB 8c010000 00010000 RESERVED
DBGSER_DMA 8c022000 00002000 RESERVED
SER_DMA 8c024000 00002000 RESERVED
IR_DMA 8c026000 00002000 RESERVED
SD_DMA 8c028000 00008000 RESERVED
EDBG 8c030000 00020000 RESERVED
CPXIPCHAIN 8c050000 00008000 RESERVED
SLEEP_BUFF 8c058000 00004000 RESERVED
DISPLAY 8c100000 00100000 RESERVED
DISPLAY
AUD_DMA 8c002000 00002000 RESERVED
DRV_GLB 8c010000 00010000 RESERVED
DBGSER_DMA 8c022000 00002000 RESERVED
SER_DMA 8c024000 00002000 RESERVED
IR_DMA 8c026000 00002000 RESERVED
SD_DMA 8c028000 00008000 RESERVED
EDBG 8c030000 00020000 RESERVED
CPXIPCHAIN 8c050000 00008000 RESERVED
SLEEP_BUFF 8c058000 00004000 RESERVED
;DISPLAY 8c100000 00100000 RESERVED
DISPLAY 8c060000 001a0000 RESERVED
5.
在（4）中修改了DISPLAY显示缓冲区的开始地址,因此要在“s2410.h”中做相应的修改：
…/WINCE420/PLATFORM/SMDK2410/INC/s2410.h
#define DMA_BUFFER_BASE 0xAC000000
#define DMA_PHYSICAL_BASE 0x30000000
//#define FRAMEBUF_BASE (DMA_BUFFER_BASE + 0x00100000)
//#define FRAMEBUF_DMA_BASE (DMA_PHYSICAL_BASE + 0x00100000)
#define FRAMEBUF_BASE (DMA_BUFFER_BASE + 0x00060000)
#define FRAMEBUF_DMA_BASE (DMA_PHYSICAL_BASE + 0x00060000)
6. 在（4）中修改了DISPLAY显示缓冲区的大小, 因此要在“s3c2410disp.cpp”中做相应的修改：
…/WINCE420/PLATFORM/SMDK2410/DRIVERS/DISPLAY/S3C2410LCD/s3c2410disp.cpp
红色部分为修改后的内容：
void S3C2410DISP::InitializeHardware (void)
{
*********
m_VirtualFrameBuffer = (DWORD)VirtualAlloc(0, (0x1A0000), MEM_RESERVE, PAGE_NOACCESS);
if (m_VirtualFrameBuffer == NULL)
{
RETAILMSG(0,(TEXT("m_VirtualFrameBuffer is not allocated/n/r")));
return;
}
else if (!VirtualCopy((PVOID)m_VirtualFrameBuffer, (PVOID)gdwLCDVirtualFrameBase, (0x1A0000), PAGE_READWRITE | PAGE_NOCACHE))
{
RETAILMSG(0, (TEXT("m_VirtualFrameBuffer is not mapped/n/r")));
VirtualFree((PVOID)m_VirtualFrameBuffer, 0, MEM_RELEASE);
return;
}
*********
}
7.
完！
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