NAND FLASH读写

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1、NANDFLASH读写HY27UF081G2A:1Gbit(128Mx8bit/64Mx16bit)NANDFlashMemory设备操作:3.1PageRead.打开电源之后，芯片默认处于读状态。也可以在写入4字节地址之后，写入命令00h和30h到命令寄存器，使能读操作。Intwoconsecutive(连续)readoperations,thesecondonedoesneed00hcommand,whichfouraddresscyclesand30hcommandinitiatesthatoperation.Second

2、readoperationalwaysrequiressetupcommandiffirstreadoperationwasexecuted(执行)usingalsorandomdata(随机读取)outcommand.Twotypesofoperationsareavailable:randomread.Therandomreadmodeisenabledwhenthepageaddressischanged.The2112bytes(X8device)or1056words(X16device)ofdatawithinthe

3、selectedpagearetransferredtothedataregistersinlessthan25us(tR).Thesystemcontroller(控制器)maydetect(检测)thecompletionofthisdatatransfer(tR)byanalyzing(分析)theoutputofR/Bpin.Oncethedatainapageisloadedintothedataregisters(一旦一页的数据被加载到数据寄存器中),theymaybereadoutin30nscycletime(3

4、.3Vdevice)bysequentiallypulsingRE.Therepetitive(重复)hightolowtransitionsoftheREclockmakethedeviceoutputthedatastartingfromtheselectedcolumnaddressuptothelastcolumnaddress.Thedevicemayoutputrandomdatainapageinsteadoftheconsecutivesequentialdatabywritingrandomdataoutput

5、command.Thecolumnaddressofnextdata,whichisgoingtobeout,maybechangedtotheaddresswhichfollowsrandomdataoutputcommand.1.命令输入CommandInput(CLE=1，ALE=0)ALE(0),CE(0)->CLE(1)->WE(0)->Command(输入并保持) ,在Command保持时拉高WE（1）WE上升沿锁存Command->CE(1)->CLE(0)->ALE(1)根据时序图所得示意程序伪码voidwrit

6、e_com(uint8com){  ALE=0; CE=0;delay20ns;  CLE=1;delay15ns; WE=0;delay15ns; IO7-0=com;delay5ns; WE=1;delay15ns; CE=1; CLE=0; ALE=1;}2.地址输入AddressInput（CLE=0，ALE=1） 3.数据输入DataInput(CLE=0，ALE=0)4.数据读出DataOutput(CLE=0，ALE=0)5.读状态寄存器  (ReadStatusRegister)6.页读取 (PageRead)7

7、.任意地址数据读取(RandomDATAOutput)command0x00->address4字节（该页首地址）->command0x30->判别忙信号delay15ns->顺序读取或者command0x05->address2字节（所要读的数据所在地址）->开始读出数据注意：注意图中的ColumnAddress对应DoutN的地址,0x50后是2字节在该页中的地址页写入 (PageProgram)command0x80->address4字节（该页首地址）->顺序写入最多2112字节->command0x10结束写->判别忙

8、信号->command0x70读状态寄存器->IO0为0写成功任意地址数据写入 (RandomDATAInput)command0x80->address4字节（该页首地址）->顺序写入或者command0x85->写入数据->command0x10结束写入->