WinCE6.0串口打印函数汇总

在 WinCE 系统启动最开始，也就是 EBoot 部分，会完成一定串口的初始化，以便在后面的工作中可以在串口中显示很多信息。这也是串口打印的最开始部分。

 

OEMReadDebugByte 、 OEMWriteDebugByte 、 OEMWriteDebugString

在 EBoot 汇编跳转到 C 语言的 main 函数后，在 blcommon.c 中的 BootLoaderMain 是第一个 C 语言函数，这里的初始化部分包含一个 OEMDebugInit 的函数，实现在 main.c 文件中，里面调用了 OEMInitDebugSerial() 函数，实现在 \WINCEROOT\PLATFORM\BSPNAME\SRC\OAL\OALLIB\debug.c 里，就是它完成了串口的打印实现，包括 OEMReadDebugByte() 、 OEMWriteDebugByte() 、 OEMWriteDebugString() 。

 

EdbgOutputDebugString 、 KITLOutputDebugString

在 BootLoaderMain 实现过程中，还会经常见到两个函数 EdbgOutputDebugString() 和 KITLOutputDebugString() ，这两个函数的实现其实是一样的，在 \WINCEROOT\PUBLIC\COMMOM\OAK\INC\halether.h 文件中有如下定义 :

#define EdbgOutputDebugString    KITLOutputDebugString

EdbgOutputDebugString() 的实现在文件 \WINCEROOT\PUBLIC\COMMOM\OAK\DRIVERS\ETHDBG\EDBGFRMT\format.c 中，具体的实现如下，其实和 printf 的实现很类似，这里就不做太多介绍了。

   

void EdbgOutputDebugString (LPCSTR sz, ...)
{
        unsigned char        c;
        va_list                 vl;
        
        va_start(vl, sz);
        
        while (*sz) {
                c = *sz++;
                switch (c) {
                case '%':
                        c = *sz++;
                        switch (c) {    
                        case 'x':
                                pOutputNumHex(va_arg(vl, unsigned long), 0);
                                break;
                        case 'B':
                                pOutputNumHex(va_arg(vl, unsigned long), 2);
                                break;
                        case 'H':
                                pOutputNumHex(va_arg(vl, unsigned long), 4);
                                break;
                        case 'X':
                                pOutputNumHex(va_arg(vl, unsigned long), 8);
                                break;
                        case 'd':
                                {
                                        long        l;
                                
                                        l = va_arg(vl, long);
                                        if (l < 0) {    
                                                pOutputByte('-');
                                                l = - l;
                                        }
                                        pOutputNumDecimal((unsigned long)l);
                                }
                                break;
                        case 'u':
                                pOutputNumDecimal(va_arg(vl, unsigned long));
                                break;
                        case 's':
                                OutputString(va_arg(vl, char *));
                                break;
                        case '%':
                                pOutputByte('%');
                                break;
                        case 'c':
                                c = va_arg(vl, unsigned char);
                                pOutputByte(c);
                                break;
                                
                        default:
                                pOutputByte(' ');
                                break;
                        }
                        break;
                case '\r':
                        if (*sz == '\n')
                                sz ++;
                        c = '\n';
                        // fall through
                case '\n':
                        pOutputByte('\r');
                        // fall through
                default:
                        pOutputByte(c);
                }
        }
        
        va_end(vl);
}

 

NKDbgPrintfW 、 OutputDebugStringW

NKDbgPrintfW() 函数同样是在文件 \WINCEROOT\PUBLIC\COMMOM\OAK\DRIVERS\ETHDBG\EDBGFRMT\format.c 中实现的，实现代码如下：

void NKDbgPrintfW(
        const WCHAR *sz, ...)
{
        unsigned char        c;
        va_list                 vl;
        
        va_start(vl, sz);
        
        while (*sz) {
                c = (unsigned char)*sz++;
                switch (c) {    
                        case (unsigned char)'%':
                        c = (unsigned char)*sz++;
                        switch (c) {    
                                case 'x':
                                pOutputNumHex(va_arg(vl, unsigned long), 0);
                                break;
                                case 'B':
                                pOutputNumHex(va_arg(vl, unsigned long), 2);
                                break;
                                case 'H':
                                pOutputNumHex(va_arg(vl, unsigned long), 4);
                                break;
                                case 'X':
                                pOutputNumHex(va_arg(vl, unsigned long), 8);
                                break;
                                case 'd': {
                                long        l;
                                
                                l = va_arg(vl, long);
                                if (l < 0) {    
                                        pOutputByte('-');
                                        l = - l;
                                }
                                pOutputNumDecimal((unsigned long)l);
                        }
                                break;
                                case 'u':
                                pOutputNumDecimal(va_arg(vl, unsigned long));
                                break;
                                case 's':
                                OutputStringW(va_arg(vl, WCHAR *));
                                break;
                                case '%':
                                pOutputByte('%');
                                break;
                                case 'c':
                                c = va_arg(vl, unsigned char);
                                pOutputByte(c);
                                break;
                                
                                default:
                                pOutputByte(' ');
                                break;
                        }
                        break;
                        case '\n':
                        pOutputByte('\r');
                        // fall through
                        default:
                        pOutputByte(c);
                }
        }
        
        va_end(vl);
}

OutputDebugStringW() 函数其实是直接调用 NKDbgPrintfW() 实现的。

 

void OutputDebugStringW(LPCWSTR fmt)
{
        NKDbgPrintfW(fmt);
}

 

RETAILMSG 、 DEBUGMSG

这两个函数是在 BSP 中最常见的了，在文件

\WINCEROOT \PUBLIC\COMMON\SDK\INC\dbgapi.h 中实现，两者的实现是一摸一样的，只是在不同的编译条件下实现的效果不同而已，都是通过上面的 NKDbgPrintfW() 函数来实现的。具体实现如下：

#define DEBUGMSG(cond,printf_exp)     \
     ((void)((cond)?(NKDbgPrintfW printf_exp),1:0))    

#define RETAILMSG(cond,printf_exp)\
    ((cond)?(NKDbgPrintfW printf_exp),1:0)