39VF400A读写代码
SoftwareDrivers
39VF400A
4 Mbit Multi-Purpose Flash
September 2001
ABOUT THE SOFTWARE
This application note provides software driver examples for 39VF400A 4 Mbit
Multi-Purpose Flash, that can be used in any microprocessor based system.
Please note that the software driver for 39VF400A is the same as the driver
for 39VF400 except the part number has been changed. Software driver examples
used in this document utilize two programming languages: (a) high -level "C"
for broad platform support and (b) optimized x86 assembly language. 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
driver in "C" language can be used with many microprocessors and
microcontrollers, while the x86 assembly language provides an optimized solution
for x86 microprocessors. A Code Segment base address equal to C000h was used in
this sample code.Software designers shall assign the segment address
appropriate to their designs.
ABOUT THE 39VF400A
Companion product datasheet for the 39VF400A should be reviewed in conjunction
with this application note for a complete understanding of the device.
Both the C and x86 assembly code in the document contain the following routines,
in this order:
Name Function
------------------------------------------------------------------
Check_SST_39VF400A 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), 1994-2001 */
/* Example "C" language Driver of 39VF400A 4 Mbit Multi-Purpose Flash*/
/* Nelson Wang, Silicon Storage Technology, Inc. */
/* */
/* Revision 1.0, Sept. 12, 2001 */
/* */
/* This file requires these external "timing"routines: */
/* */
/* 1.)Delay_150_Nano_Seconds */
/* 2.)Delay_25_Milli_Seconds */
/* 3.)Delay_100_Milli_Seconds */
/***********************************************************************/
#define FALSE 0
#define TRUE 1
#define SECTOR_SIZE 2048 /* Must be 2048 words for 39VF400A */
#define BLOCK_SIZE 32768 /* Must be 32K words for 39VF400A*/
#define SST_ID 0x00BF/* SST Manufacturer's ID code */
#define SST_39VF400A 0x2780/* SST39VF400A device code */
/* same device code as SST39VF400 */
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_100_Milli_Seconds();
/************************************************************************/
/* PROCEDURE: Check_SST_39VF400A */
/* */
/* This procedure decides whether a physical hardware device has a */
/* SST39VF400A 4 Mbit Multi-Purpose Flash installed or not. */
/* */
/* Input: */
/* None */
/* */
/* Output: */
/* return TRUE:indicates a SST39VF400A */
/* return FALSE: indicates not a SST39VF400A */
/************************************************************************/
int Check_SST_39VF400A() /* same device code as SST39VF400 */
{
WORD far *Temp;
WORD SST_id1;
WORD far *Temp1;
WORD SST_id2;
intReturnStatus;
/*Issue the Software Product ID code to 39VF400A */
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 39VF400A */
Temp= (WORD far *)0xC0000000; /* set up address to be C000:0000h */
SST_id1=*Temp; /* get first ID word */
SST_id1=SST_id1 & 0xFF; /* 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 SST39VF400A installed or not */
if ((SST_id1 == SST_ID) && (SST_id2 ==SST_39VF400A))
ReturnStatus = TRUE;
else
ReturnStatus = FALSE;
/* Issue the Soffware Product ID Exit code thus returning the 39VF400A*/
/* 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 */
/************************************************************************/
int CFI_Query()
{
WORD far *Temp1;
/*Issue the Software Product ID code to 39VF400A */
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 39VF400A */
/* 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 */
/************************************************************************/
int Erase_One_Sector (WORD far *Dst)
{
WORD far *Temp;
/*Issue the Sector Erase command to 39VF400A*/
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 */
/************************************************************************/
int Erase_One_Block (WORD far *Dst)
{
WORD far *Temp;
/*Issue the Sector Erase command to 39VF400A*/
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 = 0x5050; /* write data 0x5050 to the address */
Delay_25_Milli_Seconds(); /* Delay time = Tbe */
}
/************************************************************************/
/* PROCEDURE: Erase_Entire_Chip */
/* */
/* This procedure can be used to erase the entire chip. */
/* */
/* Input: */
/* NONE */
/* */
/* Output: */
/* NONE */
/************************************************************************/
int Erase_Entire_Chip()
{
WORD far *Temp;
/*Issue the Chip Erase command to 39VF400A*/
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= (WORD far *)0xC0005555; /* set up address to be C000:5555h*/
*Temp = 0x1010; /* write data 0x1010 to the address */
Delay_100_Milli_Seconds(); /* Delay Tsce time */
}
/************************************************************************/
/* PROCEDURE: Program_One_Word */
/* */
/* This procedure can be used to program ONE word of data to the */
/* 39VF400. */
/* */
/* NOTE:It is necessary to first erase the sector containing the */
/* word to be programmed. */
/* */
/* Input: */
/* SrcWord The WORD which will be written to the 39VF400A */
/* Dst DESTINATION address which will be written with the */
/* data passed in from Src */
/* */
/* Output: */
/* None */
/************************************************************************/
void Program_One_Word (WORD SrcWord, WORD far *Dst)
{
WORD far *Temp;
WORD far *SourceBuf;
WORD far *DestBuf;
int Index;
DestBuf = Dst;
Temp =(WORD far *)0xC0005555; /* set up address to be C000:555h */
*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 = 0xA0A0; /* write data 0xA0A0 to the address */
*DestBuf = SrcWord; /* transfer the byte to destination */
Check_Toggle_Ready(DestBuf); /* wait for TOGGLE bit to get ready */
}
/************************************************************************/
/* PROCEDURE: Program_One_Sector */
/* */
/* This procedure can be used to program a total of 2048 words of data*/
/* to the SST39VF400A. */
/* */
/* Input: */
/* Src SOURCE address containing the data which will be */
/* written to the 39VF400A */
/* Dst DESTINATION address which will be written with the */
/* data passed in from Src */
/* */
/* Output: */
/* None */
/************************************************************************/
void Program_One_Sector (WORD far *Src, WORD far *Dst)
{
WORD far *Temp;
WORD far *SourceBuf;
WORD far *DestBuf;
int Index;
SourceBuf = Src;
DestBuf = Dst;
Erase_One_Sector(Dst); /* erase the sector first */
for (Index = 0; Index < SECTOR_SIZE; Index++)
{
Temp =(WORD far *)0xC0005555;
/* set up address to be C000:555h */
*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 = 0xA0A0;
/* write data 0xA0A0 to the address */
Temp = DestBuf;
/* save the original Destination address */
*DestBuf++ = *SourceBuf++;
/* transfer data from source to destination */
Check_Toggle_Ready(Temp);
/* wait for TOGGLE bit to get ready */
}
}
/************************************************************************/
/* PROCEDURE: Program_One_Block */
/* */
/* This procedure can be used to program a total of 32k words of data */
/* to the SST39VF400A. */
/* */
/* Input: */
/* Src SOURCE address containing the data which will be */
/* written to the 39VF400A */
/* Dst DESTINATION address which will be written with the */
/* data passed in from Src */
/* */
/* Output: */
/* None */
/************************************************************************/
void Program_One_Block (WORD far *Src, WORD far *Dst)
{
WORD far *Temp;
WORD far *SourceBuf;
WORD far *DestBuf;
int Index;
SourceBuf = Src;
DestBuf = Dst;
Erase_One_Block(Dst); /* erase the sector first */
for (Index = 0; Index < BLOCK_SIZE; Index++)
{
Temp =(WORD far *)0xC0005555;
/* set up address to be C000:555h */
*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 = 0xA0A0;
/* write data 0xA0A0 to the address */
Temp = DestBuf;
/* save the original Destination address */
*DestBuf++ = *SourceBuf++;
/* transfer data from source to destination */
Check_Toggle_Ready(Temp);
/* wait for TOGGLE bit to get ready */
}
}
/************************************************************************/
/* PROCEDURE: Check_Toggle_Ready */
/* */
/* During the internal program cycle, any consecutive read operation */
/* on DQ6 will produce alternating 0's and 1's (i.e. toggling between */
/* 0 and 1). When the program cycle is completed, DQ6 of the data will*/
/* stop toggling. After the DQ6 data bit stops toggling, the device is*/
/* ready for next operation. */
/* */
/* Input: */
/* Dst must already be set-up by the caller */
/* */
/* Output: */
/* None */
/************************************************************************/
void Check_Toggle_Ready (WORD far*Dst)
{
BYTE Loop = TRUE;
WORD PreData;
WORD CurrData;
unsigned long TimeOut = 0;
PreData = *Dst;
PreData = PreData & 0x4040;
while ((TimeOut< 0x07FFFFFF) && (Loop))
{
CurrData = *Dst;
CurrData = CurrData & 0x4040;
if (PreData == CurrData)
Loop = FALSE; /* ready to exit the while loop */
PreData = CurrData;
TimeOut++;
}
}
/************************************************************************/
/* PROCEDURE: Check_Data_Polling */
/* */
/* During the internal program cycle, any attempt to read DQ7 of the */
/* last byte loaded during the page/byte-load cycle will receive the */
/* complement of the true data.Once the program cycle is completed, */
/* DQ7 will show true data. */
/* */
/* Input: */
/* Dst must already be set-up by the caller */
/* True Data is the original (true) data */
/* */
/* Output: */
/* None */
/************************************************************************/
void Check_Data_Polling (WORD far*Dst, WORD TrueData)
{
BYTE Loop = TRUE;
WORD CurrData;
unsigned long TimeOut = 0;
TrueData = TrueData &0x8080;
while ((TimeOut< 0x07FFFFFF) && (Loop))
{
CurrData = *Dst;
CurrData = CurrData & 0x8080;
if (TrueData == CurrData)
Loop = FALSE; /* ready to exit the while loop*/
TimeOut++;
}
}
8086 ASSEMBLY LANGUAGE DRIVERS
; ======================================================================
; Copyright Silicon Storage Technology, Inc. (SST), 1994-2001
; EXAMPLE 8086 assembly Drivers for SST39VF400A 4 Mbit MultiPurpose Flash
; Frank Cirimele,Silicon Storage Technology, Inc.
;
; Revision 1.0,Sept. 12, 2001
;
; This file requires these external "timing" routines:
;
; 1.)Delay_150_Nano_Seconds
; 2.)Delay_25_Milli_Seconds
; 3.)Delay_100_Milli_Seconds
; ======================================================================
SECTOR_SIZE EQU 2048 ; Must be 4096 bytes for SST39VF400A
BLOCK_SIZE EQU 32768
SST_ID EQU 00BFh; SST Manufacturer's ID code
SST_SST39VF400A EQU 2780h; SST SST39VF400A internal code, and
;is same device code as SST39VF400
ABS_SEGMENT EQU 0C000h
extrn Delay_150_Nano_Seconds:near
extrn Delay_25_Milli_Seconds:near
extrn Delay_100_Milli_Seconds:near
;=======================================================================
; PROCEDURE: Check_SST_SST39VF400A
;
; This procedure decides whether a physical hardware device has a
; SST39VF400A 4 Mbit Multi-Purpose Flash installed or not.
;
; Input:
; None
;
; Output:
; carry bit: CLEARED means a SST39VF400A is installed
; carry bit: SET means a SST39VF400A is NOT installed
;
;=======================================================================
Check_SST_SST39VF400A proc near
push ax ; save registers
push ds
pushf ; save interrupt state
; It is mandatory to maintain pushf as the last push instruction.
cli ; disable interrupts
mov ax, ABS_SEGMENT ; set up data segment
mov ds, ax
mov ds:word ptr , 0AAAAh ; issue the 3-byte product ID
mov ds:word ptr , 05555h ;command to the SST39VF400A
mov ds:word ptr , 09090h
call Delay_150_Nano_Seconds ; insert delay = Tida
mov ax, ds:
cmp ax, SST_ID ; is this a SST part?
jne CSC5 ; NO, then return Carry set
mov ax, ds:
cmp ax, SST_SST39VF400A ; is it a SST39VF400A?
jne CSC5 ; NO, then Non-SST part and
; set Carry flag
CSC4:
pop ax ; get flags from stack
and ax, 0FFFEh ; and clear carry flag
jmp short CSC6
CSC5:
pop ax ; get flags from stack
or ax, 0001h ; and set carry flag
CSC6:
push ax ; return flags to stack
;
; Issue the Software Product ID Exit code thus returning the SST39VF400A
; to the read operation mode.
;
mov ds:word ptr , 0AAAAh ; issue the 3-byte product ID
mov ds:word ptr , 05555h ;exit command to the
mov ds:word ptr , 0F0F0h ;SST39VF400A
call Delay_150_Nano_Seconds ; insert delay = Tida
popf ; restore flags
pop ds ; restore registers
pop ax
ret
Check_SST_SST39VF400A endp
;=======================================================================
; PROCEDURE: CFI_Query
;
; This procedure provides access to the CFI information embedded within
; the SST39VF400A 4 Mbit Multi-Purpose Flash device.
;
; Input:
; None
;
; Output:
; None
;
;=======================================================================
CFI_Query proc near
pushf ; save interrupt state
push ax ; save registers
push ds
cli ; disable interrupts
mov ax, ABS_SEGMENT ; set up the ds register
mov ds, ax
mov ds:word ptr , 0AAAAh ; issue the 3-byte product ID
mov ds:word ptr , 05555h ;command to the SST39VF400A
mov ds:word ptr , 09898h
call Delay_150_Nano_Seconds ; insert delay = Tida
; -----------------------------------
; Perform all CFI operations here
; NOTE:NO sample code provided
; -----------------------------------
mov ds:word ptr , 0AAAAh ; issue the 3-byte product ID
mov ds:word ptr , 05555h ; exit command to the SST39VF400A
mov ds:word ptr , 0F0F0h
call Delay_150_Nano_Seconds ; insert delay = Tida
pop ds ; restore registers
pop ax
popf ; restore flags
ret
CFI_Query endp
; =====================================================================
; PROCEDURE: Erase_One_Sector
;
; This procedure can be used to erase a sector, or total of 2048 bytes,
; in the SST39VF400A.
;
; Input:
; es:di points to the beginning address of the "Destination"
; sector which will be erased.
; ==> Note: The address MUST be on a sector boundary,
; that is, a multiple of 2048.
;
; Output:
; None
; =====================================================================
Erase_One_Sector proc near
push ax ; save register
mov es:word ptr , 0AAAAh ; send 6-byte code for
mov es:word ptr , 05555h ; sector erase
mov es:word ptr , 08080h
mov es:word ptr , 0AAAAh
mov es:word ptr , 05555h
mov ax, 03030h
mov word ptr es:, ax
call Delay_25_Milli_Seconds ; insert delay = Tse
pop ax ; restore register
ret
Erase_One_Sector endp
; =====================================================================
; PROCEDURE: Erase_One_Block
;
; This procedure can be used to erase a block, or total of 32K words,
; in the SST39VF400A.
;
; Input:
; es:di points to the beginning address of the "Destination"
; block which will be erased.
; ==> Note: The address MUST be on a block boundary,
; that is, a multiple of 32K.
;
; Output:
; None
; =====================================================================
Erase_One_Block proc near
push ax ; save register
mov es:word ptr , 0AAAAh ; send 6-byte code for
mov es:word ptr , 05555h ; block erase
mov es:word ptr , 08080h
mov es:word ptr , 0AAAAh
mov es:word ptr , 05555h
mov ax, 05050h
mov word ptr es:, ax
call Delay_25_Milli_Seconds ; insert delay = Tbe
pop ax ; restore register
ret
Erase_One_Block endp
; =====================================================================
; PROCEDURE: Erase_Entire_Chip
;
; This procedure can be used to erase the entire contents of
; SST's SST39VF400A.
;
; Input:
; none
;
; Output:
; None
; =====================================================================
Erase_Entire_Chip proc near
mov es:word ptr , 0AAAAh ; send 6-byte code for
mov es:word ptr , 05555h ; chip erase
mov es:word ptr , 08080h
mov es:word ptr , 0AAAAh
mov es:word ptr , 05555h
mov es:word ptr , 01010h
call Delay_100_Milli_Seconds ; insert delay = Tsce
ret
Erase_Entire_Chip endp
; =====================================================================
; PROCEDURE: Program_One_Word
;
; This procedure can be used to program ONE word of data to the SST39VF400A.
;
; NOTE:It is necessary to first erase the sector containing the word to
; be programmed.
;
;
; Input:
; ax WORD which will be written into the SST39VF400A.
; es:di DESTINATION address which will be written with the
; data input in ax.
;
; Output:
; None
; SI, DI:Contain their original values
; =====================================================================
Program_One_Word proc near
push ax ; save registers
push ds
mov ax, ABS_SEGMENT ; set up the ds register
mov ds, ax
mov ds:word ptr , 0AAAAh ; send 3 byte data protection
mov ds:word ptr , 05555h ;sequence to the chip
mov ds:word ptr , 0A0A0h
pop ds ; restore the byte to be
pop ax ;programmed from stack
mov word ptr es:, ax ; program the byte
call check_Toggle_Ready ; wait for valid TOGGLE bit
ret
Program_One_Word endp
; =====================================================================
; PROCEDURE: Program_One_Sector
;
; This procedure can be used to program a memory sector, or total of
; 2048 words, of the SST39VF400A.
;
; Input:
; ds:si SOURCE address containing the data which will be
; written into the SST39VF400A.
; es:di DESTINATION address which will be written with the
; data passed in for ds:si
;
; Output:
; None
; SI, DI:Contain their original values
; =====================================================================
Program_One_Sector proc near
push ax ; save registers
push bx
push di
push si
pushf ; preserve the "Direction" flag
cld ; clear "Direction" flag to
;auto-increment SI and DI
;
; Erase the sector before programming.Each erase command will erase a total
; of 2048 words for the SST39VF400A
;
call Erase_One_Sector
;
; The following loop will program a total of 2048 words to the SST39VF400A
;
mov cx, SECTOR_SIZE
POS1:
push ds
mov ax, ABS_SEGMENT
mov ds, ax
mov ds:word ptr , 0AAAAh ; send 3-byte SDP sequence
mov ds:word ptr , 05555h
mov ds:word ptr , 0A0A0h
pop ds
lodsw ; get the word to be programmed
mov bx, di ; preserve original DI temporarily
stosw ; program the word
push di ; preserve incremented DI temporarily
mov di, bx ; restore original DI
call check_Toggle_Ready ; wait for TOGGLE bit to get ready
pop di ; retrieve the updated DI
loop POS1 ; continue program more words until done
;
; Restore the registers' value from the stack
;
popf ; restore original direction flag
pop si ; restore registers
pop di
pop bx
pop ax
ret
Program_One_Sector endp
; =====================================================================
; PROCEDURE: Program_One_Block
;
; This procedure can be used to program a memory block, or a total of
; 32K words, of the SST39VF400A.
;
; Input:
; ds:si SOURCE address containing the data which will be
; written into the SST39VF400A.
; es:di DESTINATION address which will be written with the
; data passed in for ds:si
;
; Output:
; None
; SI, DI:Contain their original values
; =====================================================================
Program_One_Block proc near
push ax ; save registers
push bx
push di
push si
pushf ; preserve the "Direction" flag
cld ; clear "Direction" flag to
;auto-increment SI and DI
;
; Erase the block before programming.Each erase command will erase a total
; of 32K words of the SST39VF400A.
;
call Erase_One_Block
;
; The following loop will program a total of 32K words to SST's SST39VF400A
;
mov cx, BLOCK_SIZE
POB1:
push ds
mov ax, ABS_SEGMENT
mov ds, ax
mov ds:word ptr , 0AAAAh ; send 3-byte SDP sequence
mov ds:word ptr , 05555h
mov ds:word ptr , 0A0A0h
pop ds
lodsw ; get the word to be programmed
mov bx, di ; preserve DI temporarily
stosw ; program the word
push di ; preserve incremented DI temporarily
mov di, bx ; restore original DI
call check_Toggle_Ready ; wait for TOGGLE bit to get ready
pop di ; retrieve the updated DI
loop POB1 ; continue program more words until done
popf ; restore original direction flag
pop si ; restore registers
pop di
pop bx
pop ax
ret
Program_One_Block endp
;======================================================================
; PROCEDURE: Check_Toggle_Ready
;
; During the internal program cycle, any consecutive read operation
; on DQ6 will produce alternating 0抯 and 1抯, i.e. toggling between
; 0 and 1. When the program cycle is completed, the DQ6 data will
; stop toggling. After the DQ6 data stops toggling, the device is ready
; for the next operation.
;
; Input:
; es:di must already be set-up by the caller
;
; Output:
; None
;======================================================================
Check_Toggle_Ready proc near
push ax ; save registers
push bx
mov ax, es: ; read a word from the chip
and ax, 4040h ; mask out the TOGGLE bit (DQ6)
CTR_Tog2:
mov bx, es: ; read the same word from the chip again
and bx, 4040h ; mask out the TOGGLE bit (DQ6)
cmp ax, bx ; is DQ6 still toggling?
je CTR_Tog3 ; No, then the write operation is done
xchg ax, bx ; YES, then continue checking...
jmp short CTR_Tog2
CTR_Tog3:
pop bx ; restore registers
pop ax
ret
Check_Toggle_Ready endp
;=======================================================================
; PROCEDURE: Check_Data_Polling
;
; During the internal program cycle, any attempt to read DQ7 of the last
; byte loaded during the page/byte-load cycle will receive the complement
; of the true data.Once the program cycle is completed, DQ7 will show
; true data.
;
; Input:
; es:di must already be set-up by the caller
; bx contains the original (true) data
;
; Output:
; None
;
;=======================================================================
Check_Data_Polling proc near
push ax ; save registers
push bx
and bx, 8080h ; mask out the DQ7 bit
CDP_Tog2:
mov ax, es: ; read a word from the chip
and ax, 8080h ; mask out the DQ7 bit
cmp ax, bx ; is DQ7 still complementing?
jne CDP_Tog2
pop bx ; restore registers
pop ax
ret
Check_Data_Polling endp
这是官网上面copy 的吗 mark! 官网会给烧写代码吗？ 这是别人能用的代码，单片机操作该型号芯片 c与汇编？？？ jy11 发表于 2014-9-29 12:51
c与汇编？？？
函数实现部分都是汇编的;P 真牛 ，也不 晕 。
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