求助，关于nandflash
时间：10-02
整理：3721RD
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我用9200的A21和A22接nand flash（k9f1208）的ALE和CLE,往nandflash里写命令和地址用的是一下代码
#define AT91_SMARTMEDIA_BASE 40000000
#define AT91_SMART_MEDIA_ALE (1 << 22) /* our ALE is AD22 */
#define AT91_SMART_MEDIA_CLE (1 << 21) /* our CLE is AD21 */
#define FLASH_COMMAND (AT91_SMARTMEDIA_BASE+AT91_SMART_MEDIA_CLE )
#define FLASH_ADDRESS (AT91_SMARTMEDIA_BASE+AT91_SMART_MEDIA_ALE )
#define WRITE_ADDRESS(val) (*(volatile char *) FLASH_ADDRESS = (char)(val))
#define WRITE_COMMAND(val) (*(volatile char *) FLASH_COMMAND = (char)(val))
可是总是写不进去，哪位能指点一下，感激不尽
#define AT91_SMARTMEDIA_BASE 40000000
#define AT91_SMART_MEDIA_ALE (1 << 22) /* our ALE is AD22 */
#define AT91_SMART_MEDIA_CLE (1 << 21) /* our CLE is AD21 */
#define FLASH_COMMAND (AT91_SMARTMEDIA_BASE+AT91_SMART_MEDIA_CLE )
#define FLASH_ADDRESS (AT91_SMARTMEDIA_BASE+AT91_SMART_MEDIA_ALE )
#define WRITE_ADDRESS(val) (*(volatile char *) FLASH_ADDRESS = (char)(val))
#define WRITE_COMMAND(val) (*(volatile char *) FLASH_COMMAND = (char)(val))
可是总是写不进去，哪位能指点一下，感激不尽
哪位大哥指点一下啊，上面写错了，4000 0000应该是0x40000000
要寫入資料前，先將ALE,CLE,CE,拉為低電位，WE,RE昇為高電位，將寫入命令(80h,10h)前把CLE(Command Latch Enable)拉為高電位，每輸入一個Byte時，將WE拉至低電位，再回到高電位，命令輸入完後，就是輸入位址，輸入位址時要將CLE拉低，ALE(Address Latch Enable)拉高，地址輸入完後就是輸入資料，查command sets有讀取的命令，寫完資料後再讀取出來比對看看資料對不對。