我相信上一篇文章已经对nand flash的操作有了一定的了解，下面一起看一下程序实例：
#include "include.h"
extern void Uart_Printf(char *fmt,...);
extern void Uart_Init(int baud);
//extern void Uart_Select(int ch);
static void InitNandCfg(void)
{
rGPACON = (rGPACON&~(0x3f<<17)) |(0x3f<<17); //配置芯片引脚,因为GPACON复位后各位的值为1，所以此步也可没有
//TACLS为1个HCLK，TWRPH0为5个HCLK，TWRPH1为2个HCLK，数据宽度8位
rNFCONF =(TACLS<<12)|(TWRPH0<<8)|(TWRPH1<<4)|(0<<0);
//禁止紧锁,软件禁止上锁，禁止非法访问中断，禁止RnB中断，RnB检测上升沿，锁定备份ECC，锁定主数据区域ECC生成，初始化ECC 编码器/译码器，
//强制nFCE 为高（禁止片选）,NAND Flash 控制器使能
rNFCONT =(0<<13)|(0<<12)|(0<<10)|(0<<9)|(0<<8)|(1<<6)|(1<<5)|(1<<4)|(1<<1)|(1<<0);
}
static U32 WaitNFBusy(void) // R/B 未接好?
{
U8 stat;
WrNFCmd(QUERYCMD);//0x70,读状态命令
do
{
stat =RdNFDat();//读取NFDATA
}
while(!(stat&0x40));//，第6位，判断是否在忙
WrNFCmd(READCMD0);//写页读命令周期0
returnstat&1; //注意0为操作成功
}
static U32 ReadChipId(void)
{
U32 id,k;
NFChipEn(); //使能片选
WrNFCmd(RdIDCMD);//读ID命令
WrNFAddr(0);//写入地址0
while(NFIsBusy()); //等待不忙
id =RdNFDat()<<8;//应该是只读的厂商ID
for(k=0;k<500;k++);//延时
id |=RdNFDat();//低8位为设备ID
NFChipDs(); //关闭片选
return id;//返回ID值
}
static U16 ReadStatus(void)
{
U16 stat;
NFChipEn(); //片选使能
WrNFCmd(QUERYCMD); //读状态命令
stat = RdNFDat(); //读取状态值
NFChipDs();//关闭片选
return stat;
}
U32 EraseBlock(U32 addr)//输入参数是具体的页数，擦除的是页数所在的块
{
U8 stat;
addr &=~0x3f;//为了将地址赋给A18~A19
NFChipEn(); //片选使能
WrNFCmd(ERASECMD0); //擦除命令周期0
WrNFAddr(addr);//写地址写3个行周期A18~A19
WrNFAddr(addr>>8);//A20~A27
WrNFAddr(addr>>16);//A28
WrNFCmd(ERASECMD1); // 擦除命令周期1
stat = WaitNFBusy();//等待不忙
NFChipDs();//关闭片选
return ~stat;//返回1则操作成功
}
void ReadPage(U32 addr, U8 *buf)//并没有使用ECC校验
{
U16 i;
NFChipEn();//片选使能
WrNFCmd(READCMD0);//读命令周期0
WrNFAddr(0);//写列地址A0~A7
WrNFAddr(0);//写列地址A8~A11
WrNFAddr(addr);//行地址A12~A19
WrNFAddr(addr>>8);//行地址A20~A27
WrNFAddr(addr>>16);//行地址A28
WrNFCmd(READCMD1);//读命令周期1
InitEcc();//复位ECC
WaitNFBusy();
for(i=0; i<2048; i++)
buf[i] =RdNFDat();//读取数据存入buf中
NFChipDs();//关闭片选
}
U32 WritePage(U32 addr, U8 *buf)
{
U32 i, mecc;
U8 stat, tmp[7];
NFChipEn();
WrNFCmd(PROGCMD0);//页写命令周期1
WrNFAddr(0);
WrNFAddr(0);
WrNFAddr(addr);
WrNFAddr(addr>>8);
WrNFAddr(addr>>16);
InitEcc(); //reset mecc andsecc
MEccUnlock();//ECC解锁
for(i=0; i<2048; i++)
WrNFDat(buf[i]);//写数据
MEccLock();//锁定ECC值
mecc =RdNFMEcc();//读取ECC码
//把ECC码转化为字节型
tmp[0] = mecc&0xff;
tmp[1] =(mecc>>8)&0xff;
tmp[2] =(mecc>>16)&0xff;
tmp[3] =(mecc>>24)&0xff;
tmp[5] =0xff; //mark good block
WrNFDat(0xff);//2048，坏块标志
SEccUnlock();//解锁spare区ECC
WrNFDat(tmp[0]);//把main区的ECC写入spare区的前4个字节
WrNFDat(tmp[1]);
WrNFDat(tmp[2]);
WrNFDat(tmp[3]);
SEccLock();//锁定spare区ECC
WrNFCmd(PROGCMD1);//页写命令周期1
stat = WaitNFBusy();
NFChipDs();
return ~stat;
}
void nandMain(void)
{
U16 ID,i;
U8 buf[2048];
U32 NFBlockNO=6;
U32 NFPagesNO = 25; //第6块第25页
U32 status;
U32 BlockPages;
BlockPages=(NFBlockNO<<6)+NFPagesNO;//转化为总页数
Uart_Init(115200);
Uart_Printf("nthe main is runningn");
InitNandCfg(); //初始化函数
ID=ReadChipId();//ID 我的是现代的FLash，ID为：adda
Uart_Printf("nnand flash`s IDis:%xn",ID);
if(EraseBlock(BlockPages)&0x1==TRUE)//因为EraseBlock()的输入参数是页数，所以输入的是BlockPages
{
Uart_Printf("nblock %d iserasedn",NFBlockNO);//打印擦除的是那一块
ReadPage(BlockPages,buf);//读取擦除后的数据
Uart_Printf("nn");
for(i=0; i<2048;i++)
Uart_Printf("%4x", buf[i]); //将读出的数据进行打印
Uart_Printf("nn");
for(i=0; i<2048;i++)
{
buf[i] =i;
Uart_Printf("%4x",buf[i]);
}
Uart_Printf("nWrite data[%d block, %d page].n",NFBlockNO,NFPagesNO);
status =WritePage(BlockPages,buf);//写入数据
if(status&0x1==TRUE)//返回成功值
Uart_Printf("nWriteOK.n");
else
Uart_Printf("nWriteError.n");
for(i=0; i<2048; i++)
buf[i] =1; //为验证后边数组中的数据是来自flash，实际上相当于是在数组中擦除了flash的数据，因为如果flash擦除时内容就全为1
ReadPage(BlockPages,buf); //将读取的数据存入buf中
Uart_Printf("nRead data[%d block, %d page].n",NFBlockNO,NFPagesNO);//输出块号和页号
Uart_Printf("nn");
for(i=0; i<2048; i++)
Uart_Printf("%4x", buf[i]);//打印所读取的数据
}
else
Uart_Printf("nblock %4x erasedis badn",NFBlockNO); //否则是坏块，并打印信息
while(1);
}
本工程中用到的其他文件：
include.h:
#define rNFCONF (*(volatile unsigned *)0x4E000000)
#define rNFCONT (*(volatile unsigned *)0x4E000004)
#define rNFCMD (*(volatile unsigned*)0x4E000008)
#define rNFADDR (*(volatile unsigned*)0x4E00000C)
#define rNFCMMD (*(volatile unsigned*)0x4E000008)
#define rNFDATA (*(volatile unsigned*)0x4E000010)
#define rNFDATA8 (*(volatile unsigned char*)0x4E000010)
#define rNFMECC0 (*(volatile unsigned*)0x4E00002c)
#define rNFSTAT (*(volatile unsigned*)0x4E000020)
#define rNFESTAT0 (*(volatile unsigned*)0x4E000024)
#define rGPACON (*(volatileunsigned *)0x56000000)
#define rUTRSTAT0 (*(volatileunsigned *)0x50000010) //UART 0 Tx/Rx status
#definerULCON0 (*(volatile unsigned *)0x50000000) //UART 0 Linecontrol
#definerUCON0 (*(volatile unsigned *)0x50000004) //UART 0Control
#definerUFCON0 (*(volatile unsigned *)0x50000008) //UART 0 FIFOcontrol
#definerUBRDIV0 (*(volatile unsigned *)0x50000028) //UART 0 Baudrate divisor
#define WrUTXH0(ch) (*(volatile unsigned char*)0x50000020)=(unsigned char)(ch)
#define EnNandFlash() (rNFCONT|= 1)
#define DsNandFlash() (rNFCONT&= ~1)
#define NFChipEn() (rNFCONT&= ~(1<<1))
#define NFChipDs() (rNFCONT|= (1<<1))
#define InitEcc() (rNFCONT|= (1<<4))
#define MEccUnlock() (rNFCONT&= ~(1<<5))
#define MEccLock() (rNFCONT|= (1<<5))
#define SEccUnlock() (rNFCONT&= ~(1<<6))
#define SEccLock() (rNFCONT|= (1<<6))
#define WrNFDat8(dat) (rNFDATA8 =(dat))
#define WrNFDat32(dat) (rNFDATA =(dat))
#define RdNFDat8() (rNFDATA8) //byteaccess
#define RdNFDat32() (rNFDATA) //wordaccess
#define WrNFCmd(cmd) (rNFCMD =(cmd))
#define WrNFAddr(addr) (rNFADDR =(addr))
#define WrNFDat(dat) WrNFDat8(dat)
#define RdNFDat() RdNFDat8() //for8 bit nand flash, use byte access
#define RdNFMEcc() (rNFMECC0) //for8 bit nand flash, only use NFMECC0
#define RdNFSEcc() (rNFSECC) //for8 bit nand flash, only use low 16 bits
#define RdNFStat() (rNFSTAT)
#define NFIsBusy() (!(rNFSTAT&1))
#define NFIsReady() (rNFSTAT&1)
#define READCMD0 0
#define READCMD1 0x30
#define ERASECMD0 0x60
#define ERASECMD1 0xd0
#define PROGCMD0 0x80
#define PROGCMD1 0x10
#define QUERYCMD 0x70
#define RdIDCMD 0x90
#defineTACLS 1//7 //1-clk(0ns)
#defineTWRPH0 4//7 //3-clk(25ns)
#defineTWRPH1 1//7 //1-clk(10ns) //TACLS+TWRPH0+TWRPH1>=50ns
#define U32 unsigned int
#define U16 unsigned short
#define S32 int
#define S16 short int
#define U8 unsigned char
#define S8 char
#define TRUE 1
#define FALSE 0
#define OK 1
#define FAIL 0
///////////////////////////////////////////////////////////////////////////////////////////////
uart.c
#include "include.h"
#include <stdarg.h>
void Uart_Init(int baud)
{
int i;
rUFCON0 =0x0; //UART channel 0 FIFOcontrol register, FIFO disable
//UART0
rULCON0 =0x3; //Line control register :Normal,No parity,1 stop,8 bits
// [10] [9] [8] [7] [6] [5] [4] [3:2] [1:0]
// Clock Sel, Tx Int, Rx Int,Rx Time Out, Rx err, Loop-back, Send break, Transmit Mode, Receive Mode
// 0 1 0 , 0 1 0 0 , 01 01
// PCLK Level Pulse Disable Generate Normal Normal Interrupt or Polling
rUCON0 =0x805; // Controlregister
rUBRDIV0=((int)(50000000/16./baud+0.5) -1); //Baud rate divisiorregister 0
//UART1
for(i=0;i<100;i++);
}
//=====================================================================
void Uart_SendByte(int data)
{
if(data=='n')
{
while(!(rUTRSTAT0 & 0x2));
//Delay(1); //because the slow response of hyper_terminal
WrUTXH0('r');
}
while(!(rUTRSTAT0 &0x2)); //Wait until THR isempty.
// Delay(1);
WrUTXH0(data);
}
//====================================================================
void Uart_SendString(S8 *pt)
{
while(*pt)
Uart_SendByte(*pt++);
}
//=====================================================================
//If you don't use vsprintf(), the code size is reduced verymuch.
void Uart_Printf(S8 *fmt,...)
{
va_listap;
S8str[255];
va_start(ap,fmt);
vsprintf(str,fmt,ap);
Uart_SendString(str);
va_end(ap);
}
另外还要加上初始化文件以跳转到nandMain
以上就是一个完整的工程
