TI中文支持网您好，
6678 emif16 接16位的FLASH，对于DSP端程序来说，对FLASH操作的偏移地址是不是应该作乘2的操作？
谢谢？
Brighton Feng：
不过多少位，软件都是一样的。
但不同位宽时，硬件连线不一样。在16位宽的情况下，管脚和逻辑字节地址的对应关系如下：
EMIFA23->A1
EMIFA0->A2
EMIFA1->A3
EMIFA2->A4
……
注意16位宽时，逻辑字节地址A0不存在。
jack liu_first：
回复 Brighton Feng:
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！
Brighton Feng：
回复 jack liu_first:
没明白你的意思，能把相关代码贴出来吗？
jack liu_first：
回复 Brighton Feng:
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_WriteBytesUint32 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！
