用单片机实现对SST39VF040的操作

AT89C51对SST 之FLASH的编程操作详述Flash又名闪存，属于EEPROM,即电可擦除可编程的存储器。由于具有电可擦除的特性，并且其数据可保留上百年，所以它的应用范围非常广泛。非常适用于作为MicroChip以及DSP的外部程序存储器，或者作为需要存储大量数据的外部EEPROM。SST公司设计之39系列Multi-Purpose Flash，按照其存储的空间主要分以下几种：64K x8/128K x8/256K x8/512K x8 Byte，各自代表的芯片型号有： 39系列Flash之特性: SST39LF512/010/020/040工作电压为3.0-3.6V； SST39VF512/010/020/040工作电压为2.7V3.6V；数据保留时间100年；工作电流典型值为10mA，待机电流为1uA；快速擦除芯片时间为70ms，字节编程时间为14us。对芯片有如下操作：chip Erase operation ；sector Erase operation ；byte program operation ；byte read operation ；write operation status detection 。通过软件对芯片的操作可以访问到SST 制造商的ID；以及芯片的ID，各芯片ID如下表： TABLE 1: PRODUCT IDENTIFICATIONAddressDataManufacturers ID0000HBFHDevice IDSST39LF/VF512SST39LF/VF010SST39LF/VF020SST39LF/VF0400001H0001H0001H0001HD4HD5HD6HD7H注意：当通过软件访问了Product Identification后，必须采用软件命令退出该模式才能对芯片进行擦除、读写的操作.下面给出各软件操作指令的时序图：1. WE控制的字节编程时序：2.CE控制的字节编程时序图：3. 编程操作的状态检测时序图：4.WE控制的扇区擦除时序图：5. WE控制的芯片擦除时序图：6. 软件访问ID的时序图：7. 退出软件访问ID&复位命令的时序图：根据上面的时序图，下面给出各种软件指令操作的流程图：1字节编程流程图：2读取ID流程图：3复位命令流程图： 4芯片擦除命令流程图：5扇区擦除命令流程图：下面以SST39VF040为列，给出AT89C51对其做编程动作的source code：SST39VF040地址线为A0A18，数据线为DQ0DQ7，片选线CE，数据写使能线WE，数据读使能线OE。#define uchar unsigned char#define uint unsigned int#define ulong unsigned longsfr DataOut=0x80; /定义P0口接SST39VF040的数据线sfr Address7_0=0x90; /定义P1口接SST39VF040的地址线 A0A7sfr Address15_8=0xa0; /定义P2口接SST39VF040的地址线A8A15sbit Address16=P32; /定义P3.2接SST39VF040的地址线A16sbit Address17=P33; /定义P3.3接SST39VF040的地址线A17sbit Address18=P34; /定义P3.4接SST39VF040的地址线A18sbit Sst39vf040_Ce=P35; /定义P3.5接SST39VF040的片选线线CEsbit Sst39vf040_We=P36; /定义P3.6接SST39VF040的写使能线WE sbit Sst39vf040_Oe=P37; /定义P3.7接SST39VF040的读使能线OE struct Flash uchar manufacturer_id; uchar device_id; ulong address; Sst39vf040;/读FLASH ID的函数，入口参数：FLASH的manfacturer_ID，device_ID，出口参数返回1，0uchar Read_Id(uchar manfa_id,uchar devi_id) Sst39vf040_Ce=1; Sst39vf040_We=1; Address7_0=0x55;Address15_8=0x55;Sst39vf040_Oe=1;Sst39vf040_Ce=0;Sst39vf040_We=0;DataOut=0xaa;Sst39vf040_We=1;Address7_0=0xaa;Address15_8=0x2a; Delay10us();Sst39vf040_We=0;DataOut=0x55;Delay10us();Sst39vf040_We=1;Address7_0=0x55;Address15_8=0x55;Delay10us();Sst39vf040_We=0;DataOut=0x90;Sst39vf040_We=1;Sst39vf040_Ce=1;Delay10us();Address7_0=0x00;Address15_8=0x00;Sst39vf040_Ce=0;Sst39vf040_Oe=0;DataOut=0xff;Sst39vf040.manufacturer_id=DataOut;Address7_0=0x01;Delay10us();Sst39vf040.device_id=DataOut;Sst39vf040_Ce=1; if(Sst39vf040.manufacturer_id=manuf_ID)&(Sst39vf040.device_id=devi_ID) return 1;else return 0;/退出读ID的状态以及命令FLASH复位的函数void Read_Id_Exit(void) Sst39vf040_Ce=1; Sst39vf040_Oe=0; Sst39vf040_We=1; Address7_0=0x55; Address15_8=0x55; Sst39vf040_Ce=0; Sst39vf040_Oe=1; Sst39vf040_We=0; Delay10us(); DataOut=0xaa; Sst39vf040_We=1; Delay10us(); Address7_0=0xaa; Address15_8=0x2a; Delay10us(); Sst39vf040_We=0; Delay10us(); DataOut=0x55; Sst39vf040_We=1; Delay10us(); Address7_0=0x55; Address15_8=0x55; Delay10us(); Sst39vf040_We=0; Delay10us(); DataOut=0xf0; Sst39vf040_We=1; Sst39vf040_Ce=1; Delay10us(); Sst39vf040_Ce=0;/芯片擦除函数void Chip_Erase(void) Sst39vf040_Ce=1; Sst39vf040_Oe=0; Sst39vf040_We=1; Address18=0; Address17=0; Address16=0; Address7_0=0x55; Address15_8=0x55; Sst39vf040_Ce=0; Sst39vf040_Oe=1; Sst39vf040_We=0; DataOut=0xaa; Delay10us(); Sst39vf040_We=1; Address7_0=0xaa; Address15_8=0x2a; Delay10us(); Sst39vf040_We=0; DataOut=0x55; Delay10us(); Sst39vf040_We=1; Address7_0=0x55; Address15_8=0x55; Delay10us(); Sst39vf040_We=0; DataOut=0x80; Delay10us(); Sst39vf040_We=1; Delay10us(); Sst39vf040_We=0; DataOut=0xaa; Delay10us(); Sst39vf040_We=1; Address7_0=0xaa; Address15_8=0x2a; Delay10us(); Sst39vf040_We=0; DataOut=0x55; Delay10us(); Sst39vf040_We=1; Address7_0=0x55; Address15_8=0x55; Delay10us(); Sst39vf040_We=0; DataOut=0x10; Delay10us(); Sst39vf040_We=1; while(!Wait_Data_Pulling();/检测FLASH编程，擦除操作过程中是否完成的函数，完成后返回值1 uchar Wait_Data_Pulling(void) uchar outdata; Sst39vf040_Ce=1; Sst39vf040_We=1; Sst39vf040_Oe=1; Delay10us(); Sst39vf040_Ce=0; Sst39vf040_Oe=0; Delay10us(); DataOut=0xff; outdata=DataOut; Sst39vf040_Ce=1; Sst39vf040_Oe=1; if(outdata&0x80)=0x80) return 1; else return 0; /字节编程函数，入口参数：( byte_address：AmsA0 = A18A0 ，待写的数据：byte_data )， void We_Byte_Program(ulong byte_address,uchar byte_data) ulong temp_address; Sst39vf040_Ce=1; Sst39vf040_Oe=0; Sst39vf040_We=1; Address7_0=0x55; Address15_8=0x55; Address16=0; Address17=0; Address18=0; Sst39vf040_Ce=0; Sst39vf040_Oe=1; Sst39vf040_We=0; DataOut=0xaa; Delay10us(); Sst39vf040_We=1; Address7_0=0xaa; Address15_8=0x2a; Delay10us(); Sst39vf040_We=0; DataOut=0x55; Delay10us(); Sst39vf040_We=1; Address7_0=0x55; Address15_8=0x55; Delay10us(); Sst39vf040_We=0; DataOut=0xa0; Delay10us(); Sst39vf040_We=1; temp_address=byte_address; Address7_0=temp_address&0x0000ff; temp_address=byte_address; Address15_8=(temp_address&0x00ff00)8; temp_address=byte_address; if(temp_address&0x010000)!=0) Address16=1; else Address16=0; temp_address=byte_address; if(temp_address&0x020000)!=0) Address17=1; else Address17=0; temp_address=byte_address; if(temp_address&0x040000)!=0) Address18=1; else Address18=0; Delay10us(); Sst39vf040_We=0; DataOut=byte_data; Delay10us(); Sst39vf040_We=1; while(!Wait_Data_Pulling();/字节读函数 入口参数：待读的字节地址byte_address，返回参数值：读出的数据uchar Byte_Read(ulong byte_address) ulong temp_address; uchar temp_data; temp_address=byte_address; Sst39vf040_Ce=1; Sst39vf040_Oe=1; Sst39vf040_We=1; Address7_0=temp_address&0x000000ff; temp_address=byte_address; Address15_8=(temp_address&0x0000ff00)8; temp_address=byte_address; if(temp_address&0x00010000)!=0) Address16=1; else Address16=0; temp_address=byte_address; if(temp_address&0x00020000)!=0) Address17=1; else Address17=0; temp_addre