Ron,
Find enclosed an example of 49LF004, this flash is 100% compatible (except for the Vendor and Device ID), but you can use the erase, program... functions
In the 82802ab you have to take care of the GPIOs block, you have to unprotect the Table Lock pages by accessing the GPIOs range:
{0xFFBF0002, FWH_TBL4MB}, {0xFFBE0002, FWH_TBL4MB}, {0xFFBD0002, FWH_TBL4MB}, {0xFFBC0002, FWH_TBL4MB}, {0xFFBB0002, FWH_TBL4MB}, {0xFFBA0002, FWH_TBL4MB}, {0xFFB90002, FWH_TBL4MB}, {0xFFB80002, FWH_TBL4MB}, {0xFFB70002, FWH_TBL8MB}, {0xFFB60002, FWH_TBL8MB}, {0xFFB50002, FWH_TBL8MB}, {0xFFB40002, FWH_TBL8MB}, {0xFFB30002, FWH_TBL8MB}, {0xFFB20002, FWH_TBL8MB}, {0xFFB10002, FWH_TBL8MB}, {0xFFB00002, FWH_TBL8MB}, {0xFFBC0100, FWH_GPI } <== You have 5 bits linked to 5 GPIs (most of the time it's the cpu ratio x24, x22, x20)
GPIO = General Purpose Input Output (1 wire in input or output mode)
If you still have an issue you have to check in the chipset, for instance for an Intel system you can check the south bridge and check the register 0x4e
bResult = m_DriverInterface.hpOpenPCIDevice(0x8086, 0x2440);
if (bResult != FALSE) { // Prepare the Firmware Hub for flashing bResult = m_DriverInterface.hpReadByteConfigSpace(0x4E, bValue);
if (bResult != FALSE) { // Set enable bValue |= 1; bResult = m_DriverInterface.hpWriteByteConfigSpace(0x4E, bValue); }
m_DriverInterface.hpClosePCIDevice(); }
If still does not work check the flash protect bit on the flash, and check if the super io or the south bridge control one GPIO for the flash protection. If you don't have the layout it's difficult to find it.
Regards
Yann
---------------------------------------------------------------------------- -------------------------------------------------- Software Drivers
49LF004 4 Mbits Firmware Hub Read-Compatible Flash
September 2000 Update
ABOUT THE UPDATE The pseudo address of ABS_SEGMENT(A31-A16), A000h, needs to be replaced by FFFFh as part of FWH protocol use to decode memory size, cycle type, chip ID etc..
ABOUT THE SOFTWARE This application note provides software driver examples for 49LF004, 4 Mbits Firmware Hub Read-Compatible Flash with Top Boot-Block, that is designed to to be read-compatible to the Intel 82802 Firmware Hub(FWH) device for PC-BIOS application. 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 49LF004
Companion product datasheets for the 49LF004 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_49LF004 Check manufacturer and device ID Erase_Entire_Chip Erase the contents of the entire chip Erase_One_Sector Erase a sector of 4096 bytes Erase_One_Block Erase a block of 64 Kbytes 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), 1994-2000 */ /* Example "C" Language Drivers of 49LF004 4 Mbits Firmware Hub */ /* Read-Compatible Flash */ /* Nelson Wang, Silicon Storage Technology, Inc. */ /* */ /* Revision 1.1, September 6, 2000 */ /* */ /* 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 49LF004*/
#define SST_ID 0xBF /* SST Manufacturer's ID code */ #define SST_49LF004 0x58 /* SST 49LF004 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_49LF004 */ /* */ /* This procedure decides whether a physical hardware device has a */ /* SST 49LF004 4 Mbits Firmware Hub Read-Compatible Flash installed or */ /* not. */ /* Input: */ /* None */ /* */ /* Output: */ /* return TRUE: indicates a SST 49LF004 */ /* return FALSE: indicates not a SST 49LF004 */ /************************************************************************/
int Check_SST_49LF004() { BYTE far *Temp; BYTE SST_id1; BYTE SST_id2; int ReturnStatus;
/* Issue the Software Product ID code to 49LF004 */
Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF: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 49LF004 */
Temp = (BYTE far *)0xFFFF0000; /* set up address to be FFFF:0000h */ SST_id1 = *Temp; /* get first ID byte */ Temp = (BYTE far *)0xFFFF0001; /* set up address to be FFFF:0001h */ SST_id2 = *Temp; /* get first ID byte */
/* Determine whether there is a SST 49LF004 installed or not */
if ((SST_id1 == SST_ID) && (SST_id2 ==SST_49LF004)) ReturnStatus = TRUE; else ReturnStatus = FALSE;
/* Issue the Soffware Product ID Exit code thus returning the 49LF004*/ /* to the read operating mode */
Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF: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 (PP Mode) */ /* */ /* 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 49LF004 */
Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0x80; /* write data 0x80 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF: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 (PP Mode) */ /* */ /* 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 49LF004 */
Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0x80; /* write data 0x80 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF: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: Erase_One_Block (PP Mode) */ /* */ /* This procedure can be used to erase a total of 64 Kbytes. */ /* */ /* Input: */ /* Dst DESTINATION address at which the erase operation will */ /* start. */ /* */ /* Output: */ /* NONE */ /************************************************************************/
int Erase_One_Block(BYTE far *Dst) { BYTE far *Temp;
/* Issue the Block Erase command to 49LF004 */
Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0x80; /* write data 0x80 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:5555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = Dst /* set up starting address to be erased */ *Temp = 0x50; /* write data 0x50 to the address */
Delay_25_Milli_Seconds(); /* check DATABOOK for the most */ /* accurate value -- Tbe */ }
/************************************************************************/ /* PROCEDURE: Program_One_Byte (PP Mode) */ /* */ /* This procedure can be used to program ONE byte of date to the */ /* 49LF004. */ /* */ /* 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 49LF004. */ /* 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 *)0xFFFF5555; /* set up address to be FFFF:555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF:2AAAh */ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF: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 (PP Mode) */ /* */ /* This procedure can be used to program a total of 4096 bytes of data */ /* to the SST's 49LF004. */ /* */ /* Input: */ /* Src SOURCE address containing the data which will be */ /* written to the 49LF004. */ /* 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;
DestBuf = Dst;
Erase_One_Sector(Src); /* erase the sector first */
for (Index = 0; Index < SECTOR_SIZE; Index++) { Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF:555h */ *Temp = 0xAA; /* write data 0xAA to the address */ Temp = (BYTE far *)0xFFFF2AAA; /* set up address to be FFFF:2AAAh*/ *Temp = 0x55; /* write data 0x55 to the address */ Temp = (BYTE far *)0xFFFF5555; /* set up address to be FFFF: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 (PP Mode) */ /* */ /* 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 (PP Mode) */ /* */ /* 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), 1994-2000 ; EXAMPLE 8086 Assembly Language Drivers for 49LF004, 4 Mbits ; Firmware Hub Read-Compatible Flash with Top Boot-Block ; Frank Cirimele, Silicon Storage Technology, Inc. ; ; Revision 1.1, September 6, 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 49LF004 BLOCK_SIZE EQU 65536 ; Must be 64 Kbytes for 49LF004
SST_ID EQU 0BFh ; SST Manufacturer's ID code SST_49LF004 EQU 058h ; SST 49LF004 device code
CHIP_ERASE_COMMAND EQU 010h SECTOR_ERASE_COMMAND EQU 030h BLOCK_ERASE_COMMAND EQU 050h
ABS_SEGMENT EQU 0FFFFh
extrn Delay_150_Nano_Seconds:near extrn Delay_25_Milli_Seconds:near extrn Delay_100_Milli_Seconds:near
;======================================================================= ; PROCEDURE: Check_SST_49LF004 ; ; This procedure decides whether a physical hardware device has a SST's ; 49LF004 4 Mbits Firmware Hub Read-Compatible Flash installed or not. ; ; Input: ; None ; ; Output: ; carry bit: CLEARED means a SST 49LF004 is installed ; carry bit: SET means NOT a SST 49LF004 is NOT installed ; ;=======================================================================
Check_SST_49LF004 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 49LF004 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_49LF004 ; Is it a 49LF004? 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 49LF004 ; 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 49LF004
call Delay_150_Nano_Seconds ; insert delay = Tida
popf ; restore flags pop ds ; restore registers pop ax
ret
Check_SST_349LF004 endp
; ===================================================================== ; PROCEDURE: Erase_Entire_Chip (PP Mode) ; ; This procedure can be used to erase the entire contents of ; SST's 49LF004. ; ; Input: ; es:di points to the beginning address of the 49LF004 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 (PP Mode) ; ; This procedure can be used to erase a sector, or total of 4096 bytes, ; in the SST49LF004. ; ; 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: Erase_One_Block (PP Mode) ; ; This procedure can be used to erase a block, or total of 64 Kbytes, ; in the SST49LF004. ; ; 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 65536. ; ; Output: ; None ; =====================================================================
Erase_One_Block 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, BLOCK_ERASE_COMMAND mov byte ptr es:[di], al
call Delay_25_Milli_Seconds ; insert delay = Tbe
pop ax ; restore register
ret
Erase_One_Block endp
; ===================================================================== ; PROCEDURE: Program_One_Byte (PP Mode) ; ; This procedure can be used to program ONE byte of data to the 49LF004. ; ; NOTE: It is necessary to first erase the sector containing the byte ; to be programmed.. ; ; ; Input: ; al BYTE which will be written into the 49LF004. ; 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 (PP Mode) ; ; This procedure can be used to program a memory sector, or total of ; 4096 bytes, of the 49LF004. ; ; Input: ; ds:si SOURCE address containing the data which will be ; written into the 49LF004. ; 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 49LF004 ; call Erase_One_Sector ; ; The following loop will program a total of 4096 bytes to the SST49LF004 ; 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: Program_One_Block (PP Mode) ; ; This procedure can be used to program a memory block, or a total of ; 64 Kbytes, of the SST49LF004. ; ; Input: ; ds:si SOURCE address containing the data which will be ; written into the SST49LF004. ; es:di DESTINATION address which will be written with the ; data passed in for ds:si ; ; Output: ; None ; SI, DI: Contains the original values ; =====================================================================
Program_One_Block proc near
push ax ; save registers push bx push di push si pushf ; preserve the "Direction" flag in the FLAG ; register cld ; clear "Direction" flag in the FLAG register ; auto-increment SI, and DI ; ; Erase the block before programming. Each erase command will erase a total ; of 64 Kbytes of the SST49LF004. ; call Erase_One_Block ; ; The following loop will program a total of 64 Kbytes to SST's SST49LF004 ; mov cx, BLOCK_SIZE POB1: push ds mov ax, ABS_SEGMENT mov ds, ax mov ds:byte ptr [5555h], 0AAh ; send 3-byte SDP sequence mov ds:byte ptr [2AAAh], 055h mov ds:byte ptr [5555h], 0A0h pop ds
lodsb ; get the byte to be programmed mov bx, di ; preserve DI temporarily stosb ; program the byte push di ; preserve the updated DI temporarily mov di, bx call check_Toggle_Ready ; wait for TOGGLE bit to get ready pop di ; retrieve the updated DI loop POB1 ; continue program more bytes 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 (PP Mode) ; ; 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 be 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 (PP Mode) ; ; 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
-----Original Message----- From: Ronald G Minnich [mailto:rminnich@lanl.gov] Sent: Friday, September 06, 2002 5:17 AM To: linuxbios@clustermatic.org Subject: 82802ab and flash_rom
identification is fine, but erase block doesn't work.
mtd just flat out won't work at all for anything.
I wish these vendors would get a clue and stop making this flash programming so hard :-)
more tomorrow. ron
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