sst39vf320.txt

SST 系列Nor flash 的读写源码

Software Drivers

SST39VF320
32 Mbit Multi-Purpose Flash

May 2003


ABOUT THE SOFTWARE

This application note provides software driver examples for 39VF320 32 Mbit 
Multi-Purpose Flash, that can be used in any microprocessor based system. 
Software driver example routines provided in this document utilize high-level 
"C" programming language for broad platform support. In many cases, software 
driver routines can be inserted "as is" into the main body of code being 
developed by the system software developers. Extensive comments are included 
in each routine to describe the function of each routine. The software driver 
routines in "C" can be used with many microprocessors and microcontrollers. 

ABOUT THE SST39VF320

Companion product datasheet for the 39VF320 should be reviewed in conjunction 
with this application note for a complete understanding of the device.

The C code in this document contains the following routines, which are listed
in this order:

Name                    Function
------------------------------------------------------------------
Check_SST_39VF320       Check manufacturer and device ID
CFI_Query               CFI Query Entry/Exit command sequence
Erase_One_Sector        Erase a sector of 2048 words
Erase_One_Block         Erase a block of 32K words
Erase_Entire_Chip       Erase the contents of the entire chip
Program_One_Word        Alter data in one word
Program_One_Sector      Alter data in 2048 word sector
Program_One_Block       Alter data in 32K word block
Check_Toggle_Ready      End of internal program or erase detection using
                        Toggle bit
Check_Data_Polling      End of internal program or erase detection using
                        Data# polling


"C" LANGUAGE DRIVERS

/***********************************************************************/
/* Copyright Silicon Storage Technology, Inc. (SST), 1994-2003         */
/* Example "C" language Driver of 39VF320 32 Mbit Multi-Purpose Flash  */
/* Nelson Wang, Silicon Storage Technology, Inc.                       */
/*                                                                     */
/* Revision 1.0, May 23, 2003                                          */
/*                                                                     */
/* This file requires these external "timing"  routines:               */
/*                                                                     */
/*      1.)  Delay_150_Nano_Seconds                                    */
/*      2.)  Delay_25_Milli_Seconds                                    */
/*      3.)  Delay_50_Milli_Seconds                                    */
/***********************************************************************/

#define FALSE                   0
#define TRUE                    1

#define SECTOR_SIZE             2048    /* Must be 2048 words for 39VF320 */
#define BLOCK_SIZE              32768   /* Must be 32K words for 39VF320  */

#define SST_ID                  0x00BF  /* SST Manufacturer's ID code  */
#define SST_39VF320             0x2783  /* SST39VF320 device code      */
                                        
typedef unsigned char           BYTE;
typedef unsigned int            WORD;

/* -------------------------------------------------------------------- */
/*                       EXTERNAL ROUTINES                              */
/* -------------------------------------------------------------------- */

extern void     Delay_150_Nano_Seconds();
extern void     Delay_25_Milli_Seconds();
extern void     Delay_50_Milli_Seconds();


/************************************************************************/
/* PROCEDURE:   Check_SST_39VF320                                       */
/*                                                                      */
/* This procedure decides whether a physical hardware device has a      */
/* SST39VF320 32 Mbit Multi-Purpose Flash installed or not.             */
/*                                                                      */
/* Input:                                                               */
/*          None                                                        */
/*                                                                      */
/* Output:                                                              */
/*          return TRUE:  indicates a SST39VF320                        */
/*          return FALSE: indicates not a SST39VF320                    */
/************************************************************************/

int Check_SST_39VF320()              
{
        WORD far *Temp;
        WORD SST_id1;
        WORD far *Temp1;
        WORD SST_id2;
        int  ReturnStatus;

        /*  Issue the Software Product ID code to 39VF320   */

        Temp1 = (WORD far *)0xC0005555; /* set up address to be C000:5555h  */
        *Temp1= 0xAAAA;                 /* write data 0xAAAA to the address */
        Temp1 = (WORD far *)0xC0002AAA; /* set up address to be C000:2AAAh  */
        *Temp1= 0x5555;                 /* write data 0x5555 to the address */
        Temp1 = (WORD far *)0xC0005555; /* set up address to be C000:5555h  */
        *Temp1= 0x9090;                 /* write data 0x9090 to the address */

        Delay_150_Nano_Seconds();       /* insert delay time = Tida         */

        /* Read the product ID from 39VF320 */

        Temp  = (WORD far *)0xC0000000; /* set up address to be C000:0000h */
        SST_id1  =  *Temp;              /* get first ID word               */
        SST_id1  =  SST_id1 & 0x00FF;   /* mask of higher byte           */
        Temp1 = (WORD far *)0xC0000001; /* set up address to be C000:0001h */
        SST_id2  =  *Temp1;             /* get second ID word              */

        /* Determine whether there is a SST39VF320 installed or not */

        if ((SST_id1 == SST_ID) && (SST_id2 ==SST_39VF320))
                ReturnStatus = TRUE;
        else
                ReturnStatus = FALSE;

        /* Issue the Soffware Product ID Exit code thus returning the 39VF320 */
        /* to the read operating mode                                         */

        Temp1  = (WORD far *)0xC0005555; /* set up address to be C000:5555h   */
        *Temp1 = 0xAAAA;                 /* write data 0xAAAA to the address  */
        Temp1  = (WORD far *)0xC0002AAA; /* set up address to be C000:2AAAh   */
        *Temp1 = 0x5555;                 /* write data 0x5555 to the address  */
        Temp1  = (WORD far *)0xC0005555; /* set up address to be C000:5555h   */
        *Temp1 = 0xF0F0;                 /* write data 0xF0F0 to the address  */

        Delay_150_Nano_Seconds();        /* insert delay time = Tida          */

        return(ReturnStatus);
}


/************************************************************************/
/* PROCEDURE:   CFI_Query                                               */
/*                                                                      */
/* This procedure should be used to query for CFI information           */
/*                                                                      */
/* Input:                                                               */
/*          None                                                        */
/*                                                                      */
/* Output:                                                              */
/*          None                                                        */
/************************************************************************/

void CFI_Query()
{
        WORD far *Temp1;

        /*  Issue the Software Product ID code to 39VF320   */

        Temp1 = (WORD far *)0xC0005555; /* set up address to be C000:5555h    */
        *Temp1= 0xAAAA;                 /* write data 0xAAAA to the address   */
        Temp1 = (WORD far *)0xC0002AAA; /* set up address to be C000:2AAAh    */
        *Temp1= 0x5555;                 /* write data 0x5555 to the address   */
        Temp1 = (WORD far *)0xC0005555; /* set up address to be C000:5555h    */
        *Temp1= 0x9898;                 /* write data 0x9898 to the address   */

        Delay_150_Nano_Seconds();       /* insert delay time = Tida           */

        /* --------------------------------- */
        /*  Perform all CFI operations here  */
        /*  NOTE:  no sample code provided   */
        /* --------------------------------- */

        /* Issue the CFI Exit code thus returning the 39VF320 */
        /* to the read operating mode                          */

        Temp1  = (WORD far *)0xC0005555; /* set up address to be C000:5555h   */
        *Temp1 = 0xAAAA;                 /* write data 0xAAAA to the address  */
        Temp1  = (WORD far *)0xC0002AAA; /* set up address to be C000:2AAAh   */
        *Temp1 = 0x5555;                 /* write data 0x5555 to the address  */
        Temp1  = (WORD far *)0xC0005555; /* set up address to be C000:5555h   */
        *Temp1 = 0xF0F0;                 /* write data 0xF0F0 to the address  */

        Delay_150_Nano_Seconds();        /* insert delay time = Tida          */
}


/************************************************************************/
/* PROCEDURE:   Erase_One_Sector                                        */
/*                                                                      */
/* This procedure can be used to erase a total of 2048 words.           */
/*                                                                      */
/* Input:                                                               */
/*      Dst     DESTINATION address where the erase operation starts    */
/*                                                                      */
/* Output:                                                              */
/*      NONE                                                            */
/************************************************************************/

void Erase_One_Sector (WORD far *Dst)
{
        WORD far *Temp;

        /*  Issue the Sector Erase command to 39VF320  */

        Temp  = (WORD far *)0xC0005555; /* set up address to be C000:5555h  */
        *Temp = 0xAAAA;                 /* write data 0xAAAA to the address */
        Temp  = (WORD far *)0xC0002AAA; /* set up address to be C000:2AAAh  */
        *Temp = 0x5555;                 /* write data 0x5555 to the address */
        Temp  = (WORD far *)0xC0005555; /* set up address to be C000:5555h  */
        *Temp = 0x8080;                 /* write data 0x8080 to the address */
        Temp  = (WORD far *)0xC0005555; /* set up address to be C000:5555h  */
        *Temp = 0xAAAA;                 /* write data 0xAAAA to the address */
        Temp  = (WORD far *)0xC0002AAA; /* set up address to be C000:2AAAh  */
        *Temp = 0x5555;                 /* write data 0x5555 to the address */

        Temp  = Dst;                  /* set up starting address to be erased */
        *Temp = 0x3030;                 /* write data 0x3030 to the address */
        Delay_25_Milli_Seconds();       /* Delay time = Tse                 */
}


/************************************************************************/
/* PROCEDURE:   Erase_One_Block                                         */
/*                                                                      */
/* This procedure can be used to erase a total of 32K words.            */
/*                                                                      */
/* Input:                                                               */
/*      Dst     DESTINATION address where the erase operation starts    */
/*                                                                      */
/* Output:                                                              */
/*      NONE                                                            */
/************************************************************************/

void Erase_One_Block (WORD far *Dst)
{
        WORD far *Temp;

        /*  Issue the Sector Erase command to 39VF320  */