6678 emif16 16位访问的问题

Brighton Feng ，

您好，我看    【开发例程共享】Keystone1 软件开发包 K1_STK_1010.zip中的EMIF例程，里面有关于nor flash部分是16位访问，其中的程序 对flash读写命令其偏移地址作了乘2的操作，读写数据时，地址增量为+2，等价于偏移地址作了乘2的操作。而实事上这样读写flash才没有问题？

谢谢！

没明白你的意思，能把相关代码贴出来吗？

您好，

以下是 例程的部分相关代码

#define FLASH_BUS_WIDTH_1_BYTE 1
#define FLASH_BUS_WIDTH_2_BYTES 2

static void NOR_flashWriteCmd (NOR_InfoHandle hNorInfo, Uint32 blkAddr, Uint32 offset, Uint32 cmd)
{
Uint32 addr= blkAddr + offset*hNorInfo->busWidth;
if (FLASH_BUS_WIDTH_1_BYTE==hNorInfo->busWidth)
*(Uint8 *)addr = (Uint8)cmd;
else /*FLASH_BUS_WIDTH_2_BYTES*/
*(Uint16 *)addr = (Uint16)cmd;
}

// NOR_WriteBytes
Uint32 NOR_writeBytes( NOR_InfoHandle hNorInfo, Uint32 writeAddress, Uint32 numBytes, Uint32 readAddress)
{
Int32 i;
Uint32 retval = E_PASS;

if(FLASH_BUS_WIDTH_2_BYTES == hNorInfo->busWidth)
{
if (writeAddress & 0x00000001)
{
puts("address is not aligned to 2-byte boundary");
return E_FAIL;
}

if (numBytes & 0x00000001)
{
puts("number of bytes is not even");
return E_FAIL;
}
}

while (numBytes > 0)
{
if( (numBytes < hNorInfo->bufferSize) || (writeAddress & (hNorInfo->bufferSize-1) ))
{
if ((*Flash_Write)(hNorInfo, writeAddress, NOR_flashReadData(hNorInfo,readAddress,0) ) != E_PASS)
{
puts("Normal write failed.");
retval = E_FAIL;
}
else
{
numBytes -= hNorInfo->busWidth;
writeAddress += hNorInfo->busWidth;
readAddress += hNorInfo->busWidth;
}
}
else
{
// Try to use buffered writes
if((*Flash_BufferWrite)(hNorInfo, writeAddress, (volatile Uint8 *)readAddress, hNorInfo->bufferSize) == E_PASS)
{
numBytes -= hNorInfo->bufferSize;
writeAddress += hNorInfo->bufferSize;
readAddress += hNorInfo->bufferSize;
}
else
{
puts("Buffered write failed. Trying normal write");
// Try normal writes as a backup
for(i = 0; i<hNorInfo->bufferSize; i+= hNorInfo->busWidth)
{
if ((*Flash_Write)(hNorInfo, writeAddress, NOR_flashReadData(hNorInfo,readAddress,0) ) != E_PASS)
{
puts("Normal write also failed");
retval = E_FAIL;
break;
}
else
{
numBytes -= hNorInfo->busWidth;
writeAddress += hNorInfo->busWidth;
readAddress += hNorInfo->busWidth;
}
}
}
}

// Output status info on the write operation
if (retval == E_PASS)
{
/*print progress*/
if ( (0==(writeAddress & 0xFFFFF)) || (numBytes == 0) )
{
printf("NOR Write OK through 0x%x\n", writeAddress);
}
}
else
{
puts( "NOR Write Failed...Aborting!");
return E_FAIL;
}
}

return retval;
}

谢谢！