Software Drivers 39SF040 4 Mbit(512K x 8) Multi-Purpose Flash September 2001 ABOUT THE SOFTWARE This application note provides software driver examples for 39SF040, 4 Mbit (512K x 8) Multi-Purpose Flash, that can be used in any microprocessor based system. Software driver examples used in this document utilize two programming languages: (a) high -level "C" for broad platform support and (b) optimized 8086 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 8086 assembly language provides an optimized solution for 8086 microprocessors. ABOUT THE 39SF040 Companion product datasheets for the 39SF040 should be reviewed in conjunction with this application note for a complete understanding of the device. Both the C and 8086 assembly code in the document contain the following routines, in this order: Name Function ------------------------------------------------------------------ Check_SST_39SF040 Check manufacturer and device ID Erase_Entire_Chip Erase the contents of the entire chip Erase_One_Sector Erase a sector of 4096 bytes Program_One_Byte Alter data in one byte Program_One_Sector Alter data in 4096 bytes sector 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 Drivers of 39SF040 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 4096 /* Must be 4096 bytes for 39SF040 */ #define SST_ID 0xBF /* SST Manufacturer's ID code */ #define SST_39SF040 0xB7 /* SST 39SF040 device code */ typedef unsigned char BYTE; /* -------------------------------------------------------------------- */ /* EXTERNAL ROUTINES */ /* -------------------------------------------------------------------- */ extern void Delay_150_Nano_Seconds(); extern void Delay_25_Milli_Seconds(); extern void Delay_100_Milli_Seconds(); *************************************************************************/ /* PROCEDURE: Check_SST_39SF040 */ /* */ /* This procedure decides whether a physical hardware device has a */ /* SST 39SF040 4 Mbit Multi-Purpose Flash installed or not. */ /* */ /* Input: */ /* None */ /* */ /* Output: */ /* return TRUE: indicates a SST 39SF040 */ /* return FALSE: indicates not a SST 39SF040 */ /************************************************************************/ int Check_SST_39SF040() { BYTE far *Temp; BYTE SST_id1; BYTE SST_id2; int ReturnStatus; /* Issue the Software Product ID code to 39SF040 */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xA0002AAA; /* set up address to be A000:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0x90; /* write data 0x90 to the address */ Delay_150_Nano_Seconds(); /* check DATABOOK for the most */ /* accurate value -- Tida */ /* Read the product ID from 39SF040 */ Temp = (BYTE far *)0xA0000000; /* set up address to be A000:0000h */ SST_id1 = *Temp; /* get first ID byte */ Temp = (BYTE far *)0xA0000001; /* set up address to be A000:0001h */ SST_id2 = *Temp; /* get first ID byte */ /* Determine whether there is a SST 39SF040 installed or not */ if ((SST_id1 == SST_ID) && (SST_id2 ==SST_39SF040)) ReturnStatus = TRUE; else ReturnStatus = FALSE; /* Issue the Soffware Product ID Exit code thus returning the 39SF040 */ /* to the read operating mode */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xA0002AAA; /* set up address to be A000:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp =0xF0; /* write data 0xF0 to the address */ Delay_150_Nano_Seconds(); /* check DATABOOK for the most */ /* accurate value -- Tida */ return (ReturnStatus); } *************************************************************************/ /* PROCEDURE: Erase_Entire_Chip */ /* */ /* This procedure can be used to erase the entire chip. */ /* */ /* Input: */ /* NONE */ /* */ /* Output: */ /* NONE */ /************************************************************************/ int Erase_Entire_Chip() { BYTE far *Temp; /* Issue the Sector Erase command to 39SF040 */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xA0002AAA; /* set up address to be A000:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0x80; /* write data 0x80 to the address */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xA0002AAA; /* set up address to be A000:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0x10; /* write data 0x10 to the address */ Delay_100_Milli_Seconds(); /* check DATABOOK for the most */ /* accurate value -- Tsce */ } *************************************************************************/ /* PROCEDURE: Erase_One_Sector */ /* */ /* This procedure can be used to erase a total of 4096 bytes. */ /* */ /* Input: */ /* Dst DESTINATION address at which the erase operation will */ /* start. */ /* */ /* Output: */ /* NONE */ /************************************************************************/ int Erase_One_Sector(BYTE far *Dst) { BYTE far *Temp; /* Issue the Sector Erase command to 39SF040 */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xA0002AAA; /* set up address to be A000:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0x80; /* write data 0x80 to the address */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xA0002AAA; /* set up address to be A000:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = Dst /* set up starting address to be erased */ *Temp = 0x30; /* write data 0x30 to the address */ Delay_25_Milli_Seconds(); /* check DATABOOK for the most */ /* accurate value -- Tse */ } /************************************************************************/ /* PROCEDURE: Program_One_Byte */ /* */ /* This procedure can be used to program ONE byte of date to the */ /* 39SF040. */ /* */ /* NOTE: It is mandatory that the sector containing the byte to be */ /* programmed was ERASED first. */ /* */ /* Input: */ /* SrcByte The BYTE which will be written to the 39SF040. */ /* Dst DESTINATION address which will be written with the */ /* data passed in from SrcByte */ /* */ /* Output: */ /* None */ /************************************************************************/ void Program_One_Byte (BYTE SrcByte, BYTE far *Dst) { BYTE far *SourceBuf; BYTE far *DestBuf; int Index; DestBuf = Dst; Temp = (BYTE far *)0xA0005555; /* set up address to be A000:555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xA0002AAA; /* set up address to be A000:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h */ *Temp = 0xA0; /* write data 0xA0 to the address */ *DestBuf = SrcByte; /* 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 4096 bytes of data */ /* to the SST's 39SF040. */ /* */ /* Input: */ /* Src SOURCE address containing the data which will be */ /* written to the 39SF040. */ /* Dst DESTINATION address which will be written with the */ /* data passed in from Src */ /* */ /* Output: */ /* None */ /************************************************************************/ void Program_One_Sector (BYTE far *Src, BYTE far *Dst) { BYTE far *Temp; BYTE far *SourceBuf; BYTE far *DestBuf; int Index; SourceBuf = Src; DestBuf = Dst; Erase_One_Sector(Src); /* erase the sector first */ for (Index = 0; Index < SECTOR_SIZE; Index++) { Temp = (BYTE far *)0xA0005555; /* set up address to be A000:555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xA0002AAA; /* set up address to be A000:2AAAh*/ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xA0005555; /* set up address to be A000:5555h*/ *Temp = 0xA0; /* write data 0xA0 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 set-up by the caller */ /* */ /* Output: */ /* None */ /************************************************************************/ void Check_Toggle_Ready (BYTE far *Dst) { BYTE Loop = TRUE; BYTE PreData; BYTE CurrData; unsigned long TimeOut = 0; PreData = *Dst; PreData = PreData & 0x40; while ((TimeOut< 0x07FFFFFF) && (Loop)) { CurrData = *Dst; CurrData = CurrData & 0x40; 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 */ /* TrueData this is the original (true) data */ /* */ /* Output: */ /* None */ /************************************************************************/ void Check_Data_Polling (BYTE far *Dst, BYTE TrueData) { BYTE Loop = TRUE; BYTE CurrData; unsigned long TimeOut = 0; TrueData = TrueData & 0x80; while ((TimeOut< 0x07FFFFFF) && (Loop)) { CurrData = *Dst; CurrData = CurrData & 0x80; 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 Language Drivers for 39SF040 4 Mbit(512 x 8) ; Multi-Purpose Flash ; Frank Cirimele, Silicon Storage Technology, Inc. ; ; Revision 1.0, Sept. 12, 2000 ; ; 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 4096 ; Must be 4096 bytes for 39SF040 SST_ID EQU 0BFh ; SST Manufacturer's ID code SST_39SF040 EQU 0B7h ; SST 39SF040 device code CHIP_ERASE_COMMAND EQU 010h SECTOR_ERASE_COMMAND EQU 030h ABS_SEGMENT EQU 0A000h extrn Delay_150_Nano_Seconds:near extrn Delay_25_Milli_Seconds:near extrn Delay_100_Milli_Seconds:near ;======================================================================= ; PROCEDURE: Check_SST_39SF040 ; ; This procedure decides whether a physical hardware device has a SST's ; 39SF040 4 Mbit(512 x 8) Multi-Purpose Flash installed or not. ; ; Input: ; None ; ; Output: ; carry bit: CLEARED means a SST 39SF040 is installed ; carry bit: SET means NOT a SST 39SF040 is NOT installed ; ;======================================================================= Check_SST_39SF040 proc near push ax ; preserve registers’ value push ds pushf ; save interrupt state ; It is mandatory to maintain pushf as the last push instruction. cli mov ax, ABS_SEGMENT mov ds, ax mov ds:byte ptr [5555h], 0AAh ; issue the 3-byte product ID mov ds:byte ptr [2AAAh], 055h ; command to the 39SF040 mov ds:byte ptr [5555h], 090h call Delay_150_Nano_Seconds ; insert delay = Tida mov al, ds:[0] cmp al, SST_ID ; is this a SST part? jne CSC5 ; NO, then return Carry set mov al,ds:[1] cmp al, SST_39SF040 ; Is it a 39SF040? 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 ; save the result on the STACK CSC6: push ax ; return flags to stack ; ; Issue the Software Product ID Exit code thus returning the 39SF040 ; to the read operation mode. ; mov ds:byte ptr [5555h], 0AAh ; issue the 3-byte product ID mov ds:byte ptr [2AAAh], 055h ; exit command sequence to mov ds:byte ptr [5555h], 0F0h ; the 39SF040 call Delay_150_Nano_Seconds ; insert delay = Tida popf ; restore flags pop ds ; restore registers pop ax ret Check_SST_39SF040 endp ; ===================================================================== ; PROCEDURE: Erase_Entire_Chip ; ; This procedure can be used to erase the entire contents of ; SST's 39SF040. ; ; Input: ; es:di points to the beginning address of the 39SF040 chip ; which will be erased. ; ; Output: ; None ; ===================================================================== Erase_Entire_Chip proc near mov es:byte ptr [5555h], 0AAh ; issue 6-byte chip mov es:byte ptr [2AAAh], 055h ; erase command sequence mov es:byte ptr [5555h], 080h mov es:byte ptr [5555h], 0AAh mov es:byte ptr [2AAAh], 055h mov es:byte ptr [5555h], CHIP_ERASE_COMMAND call Delay_100_Milli_Seconds ; insert delay = Tsce ret Erase_Entire_Chip endp ; ===================================================================== ; PROCEDURE: Erase_One_Sector ; ; This procedure can be used to erase a sector, or total of 4096 bytes, ; in the SST39SF040. ; ; Input: ; es:di points to the beginning address of the "Destination" address ; which will be erased. ; ==> Note: The address MUST be on a sector boundary, ; that is, a multiple of 4096. ; ; Output: ; None ; ===================================================================== Erase_One_Sector proc near push ax ; save register mov es:byte ptr [5555h], 0AAh ; send 6-byte code for mov es:byte ptr [2AAAh], 055h ; sector erase mov es:byte ptr [5555h], 080h mov es:byte ptr [5555h], 0AAh mov es:byte ptr [2AAAh], 055h mov al, SECTOR_ERASE_COMMAND mov byte ptr es:[di], al call Delay_25_Milli_Seconds ; insert delay = Tse pop ax ; restore register ret Erase_One_Sector endp ; ===================================================================== ; PROCEDURE: Program_One_Byte ; ; This procedure can be used to program ONE byte of data to the 39SF040. ; ; NOTE: It is necessary to first erase the sector containing the byte ; to be programmed.. ; ; ; Input: ; al BYTE which will be written into the 39SF040. ; es:di DESTINATION address which will be written with the ; data input in al. ; ; Output: ; None ; ES, DI: Contain their original values ; ===================================================================== Program_One_Byte proc near push ax ; save registers push ds mov ax, ABS_SEGMENT ; set up ds register mov ds, ax mov ds:byte ptr [5555h], 0AAh ; send 3 byte data protection mov ds:byte ptr [2AAAh], 055h ; sequence to the chip mov ds:byte ptr [5555h], 0A0h pop ds pop ax ; restore the byte to be ; programmed from stack mov byte ptr es:[di], al ; program the byte call check_Toggle_Ready ; wait for valid TOGGLE bit ret Program_One_Byte endp ; ===================================================================== ; PROCEDURE: Program_One_Sector ; ; This procedure can be used to program a memory sector, or total of ; 4096 bytes, of the SST39SF040. ; ; Input: ; ds:si SOURCE address containing the data which will be ; written into the 39SF040. ; es:di DESTINATION address which will be written with the ; data passed in for ds:si ; ; Output: ; None ; SI, DI: Contains their original values ; ===================================================================== Program_One_Sector proc near push ax ; save registers 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 4096 bytes for the 39SF040 ; call Erase_One_Sector ; ; The following loop will program a total of 4096 bytes to the SST39SF040 ; DRP1: push ds mov ax, ABS_SEGMENT mov ds, ax mov ds:byte ptr [5555h], 0AAh ;3 bytes of "enable protection" mov ds:byte ptr [2AAAh], 055h ; sequence to the chip mov ds:byte ptr [5555h], 0A0h pop ds lodsb ; get the byte to be programmed mov ax, di ; preserve original DI temporarily stosb ; program the byte push di ; preserve incremented DI temporarily mov di, ax ; restore original DI call check_Toggle_Ready ; wait for TOGGLE bit to get ready pop di ; retrieve the updated DI loop DRP1 ; continue program more bytes until done popf ; restore original direction flag pop si ; restore registers pop di pop ax ret Program_One_Sector endp ;====================================================================== ; 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, 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 set-up by the caller ; ; Output: ; None ;====================================================================== Check_Toggle_Ready proc near push ax ; save register mov al, es:[di] ; read a byte form the chip and al,40h ; mask out the TOGGLE bit (DQ6) CTR_Tog2: mov ah, es:[di] ; read the same byte from the chip again and ah, 40h ; mask out the TOGGLE bit (DQ6) cmp al, ah ; is DQ6 still toggling? je CTR_Tog3 ; No, then the write operation is done xchg ah, al ; YES, then continue checking... jmp short CTR_Tog2 CTR_Tog3: pop ax ; restore register 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 ; bl contains the original (true) data ; ; Output: ; None ; ;======================================================================= Check_Data_Polling proc near push ax ; save registers push bx and bl, 80h ; mask out the DQ7 bit CDP_Tog2: mov al, es:[di] ; read a byte from the chip and al,80h ; mask out the DQ7 bit cmp al,bl ; is DQ7 still complementing? jne CDP_Tog2 pop bx ; restore registers pop ax ret Check_Data_Polling endp