//SST39VF01B/SST39VF02B
// Mbit Multi-Purpose Flash (MPF+)
//
//June 2005
//
//ABOUT THE SOFTWARE
//
//This application note provides a software driver example for 39VF01B/39VF02B
// Mbit Multi-Purpose Flash (MPF+) that can be used in any microprocessor based
//system.
//
//The SST39VF01B supports bottom boot block protection, and the SST39VF02B
//supports top boot block protection. The boot block memory area is protected when
//WP# is low and unprotected when WP# is high.
//
//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 SST39VF01B/SST39VF02B
//
//Companion product datasheet for 39VF01/39VF02 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_39VF0XB Check manufacturer and device ID
//CFI_Query CFI Query Entry/Exit command sequence
//SecID_QuerySecID 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
//SecID_Lock_StatusCheck the Lock Status of Security ID segment
//User_SecID_Word_Program Write data into User Security ID Segment
//User_SecID_Lock_Out Lock out the User Security ID Segment
//Erase_SuspendSuspend Sector/Block Erase operation
//Erase_ResumeResume Sector/Block Erase operation
//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), 1994-2005 */
/* Example "C" language Driver of 39VF0X Mbit MPF+ Device */
/* Verified by Yonglin, Silicon Storage Technology, Inc. */
/* */
/* Revision 1.0, June 17, 2005 */
/*
*/
/* This file requires these external "timing" routines: */
/* */
/* 1.) Delay_10_Micro_Seconds */
/* 2.) Delay_20_Micro_Seconds */
/* 3.) Delay_150_Nano_Seconds */
/* 4.) Delay_25_Milli_Seconds */
/* 5.) Delay_50_Milli_Seconds */
/***********************************************************************/
#define FALSE 0
#define TRUE 1
#define SECTOR_SIZE 2048 // Must be 2048 words for 39VF0XB
#define BLOCK_SIZE 32768 // Must be 32K words for 39VF0XB
#define SST_ID 0x00BF // SST Manufacturer's ID code
#define SST_39VF01B 0x236D // SST39VF01B device code
#define SST_39VF02B 0x236C // SST39VF02B device code
typedef unsigned char BYTE; // BYTE is 8-bit in length
//typedef unsigned int WORD; // WORD is 16-bit in length
typedef unsigned short WORD; // WORD is 16-bit in length, ARM
//typedef unsigned long int Uint32; // Uint32 is 32-bit in length
typedef unsigned int Uint32; // Uint32 is 32-bit in length, ARM
//Uint32 system_base = 0x4000000; // 4GByte System Memory Address.
#define system_base 0x4000000
// This sample code uses 0x4000000 as the system_base address in ARM system.
// The user should modify this address accordingly.
//#define sysAddress(offset) ((volatile WORD *)(system_base + offset))
#define sysAddress(offset) ((volatile WORD *)(system_base + (((WORD)offset)<<1))) //For ARM CPU
#define MAX_TIMEOUT0x07FFFFFF // A ceiling constant used by Check_Toggle_
// Ready() and Check_Data_Polling().
// The user should modify this constant accordingly.
// --------------------------------------------------------------------
// EXTERNAL ROUTINES
// --------------------------------------------------------------------
extern void Delay_10_Micro_Seconds();
extern void Delay_20_Micro_Seconds();
extern void Delay_150_Nano_Seconds();
extern void Delay_25_Milli_Seconds();
extern void Delay_50_Milli_Seconds();
// --------------------------------------------------------------------
int Check_SST_39VF0XB(void);
void CFI_Query(WORD*);
void SecID_Query(WORD*, WORD*);
int Erase_One_Sector(Uint32);
int Erase_One_Block (Uint32);
int Erase_Entire_Chip(void);
int Program_One_Word (WORD*, Uint32);
int Program_One_Sector (WORD*, Uint32);
int Program_One_Block (WORD *Src, Uint32 Dst);
int SecID_Lock_Status(void);
int User_SecID_Word_Program (WORD*, WORD*, int);
void User_SecID_Lock_Out (void);
void Erase_Suspend (void);
void E
rase_Resume (void);
int Check_Toggle_Ready (Uint32);
int Check_Data_Polling (Uint32, WORD);
/************************************************************************/
/* PROCEDURE: Check_SST_39VF0XB */
/* */
/* This procedure decides whether a physical hardware device has a */
/* SST39VF0XB Mbit MPF+ Device installed or not. */
/* */
/* Input: */
/* None */
/* */
/* Output: */
/* return TRUE: indicates a SST39VF0XB */
/* return FALSE: indicates not a SST39VF0XB */
/************************************************************************/
int Check_SST_39VF0XB(void)
{
WORD SST_id1;
WORD SST_id2;
int ReturnStatus;
// Issue the Software Product ID code to 39VF0XB
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x0090; // write data 0x0090 to device addr 0x555
Delay_150_Nano_Seconds(); // Tida Max 150ns for 39VF0XB
// Read the product ID from 39VF0XB
SST_id1 = *sysAddress(0x0000); // get first ID byte
SST_id2 = *sysAddress(0x0001); // get second ID byte
// ------------------------------------------------------------
// Determine whether there is a SST 39VF01B installed or not
// use the following code:
//if ((SST_id1 == SST_ID) && (SST_id2 == SST_39VF01B))
// ReturnStatus = TRUE;
//else
// ReturnStatus = FALSE;
// ------------------------------------------------------------
// Or determine whether there is a SST 39VF02B installed or not
// use the following code:
if ((SST_id1 == SST_ID) && (SST_id2 == SST_39VF02B))
ReturnStatus = TRUE;
else
ReturnStatus = FALSE;
// ------------------------------------------------------------
// Issue the Software Product ID Exit code, thus returning the
// 39VF0X to the normal operation.
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x00F0; // write data 0x00F0 to device addr 0x555
Delay_150_Nano_Seconds(); // Tida Max 150ns for 39VF0XB
return (ReturnStatus);
}
/************************************************************************/
/* PROCEDURE: CFI_Query
*/
/* */
/* This procedure should be used to query for CFI information */
/* */
/* Input: */
/* SrcSource address to store CFI_Query data string*/
/* */
/* Output: */
/* None */
/************************************************************************/
void CFI_Query(WORD *Src)
{
WORD index;
// Issue the CFI Query entry code to 39VF0X
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x0098; // write data 0x0098 to device addr 0x555
Delay_150_Nano_Seconds(); // insert delay time = Tida
// ----------------------------------------------------------
// Perform all CFI operations here:
// CFI_Query_address is from 0010H--0034H
for ( index = 0x0010; index <= 0x0034; index++)
{
*Src = *sysAddress(index);
++Src;
// CFI query data is stored in user-defined memory space.
}
// ----------------------------------------------------------
// Issue the CFI Exit code thus returning the 39VF0X
// to the read operating mode
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x00F0; // write data 0x00F0 to device addr 0x555
Delay_150_Nano_Seconds(); // insert delay time = Tida
}
/************************************************************************/
/* PROCEDURE: SecID_Query */
/* */
/* This procedure should be used to query for Security ID information. */
/* */
/* Input: */
/* SST_SecIDSource address to store SST SecID string*/
/* User_SecIDSource address to store User SecID string*/
/* */
/* Output: */
/* None */
/************************************************************************/
void SecID_Query(WORD *SST_SecID, WORD *User_SecID)
{
WORD index;
// Issue the SecID Entry code to 39VF0X
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddr
ess(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x0088; // write data 0x0088 to device addr 0x555
Delay_150_Nano_Seconds(); // insert delay time = Tida
// Perform all Security ID operations here:
// SST programmed segment is from address 000000H--000007H,
// User programmed segment is from address 000010H--000017H.
for (index = 0x0000; index <= 0x0007; index++)
{
*SST_SecID = *sysAddress(index);
++SST_SecID;
*User_SecID = *sysAddress(index+0x0010);
++User_SecID;
// Security query data is stored in user-defined memory space.
}
// Issue the Sec ID Exit code thus returning the 39VF0X
// to the read operating mode
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x00F0; // write data 0x00F0 to device addr 0x555
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: */
/* return TRUE: indicates success in sector-erase */
/* return FALSE: indicates failure in sector-erase */
/************************************************************************/
int Erase_One_Sector(Uint32 Dst)
{
Uint32 DestBuf = Dst;
int ReturnStatus;
// Issue the Sector Erase command to 39VF0X
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x0080; // write data 0x0080 to device addr 0x555
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(DestBuf) = 0x0050; // write data 0x0050 to device sector addr
ReturnStatus = Check_Toggle_Ready(DestBuf);// wait for TOGGLE bit ready
return ReturnStatus;
}
/************************************************************************/
/* 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: */
/* return TRUE: indicates success in block-erase */
/* return FALSE: indicates failure in block-erase */
/************************************************************************/
int Erase_One_Block (Uint32 Dst)
{
Uint32 DestBuf = Dst;
int ReturnStatus;
// Issue the Block Erase command to 39VF0X
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x0080; // write data 0x0080 to device addr 0x555
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(DestBuf) = 0x0030; // write data 0x0030 to device sector addr
ReturnStatus = Check_Toggle_Ready(DestBuf); // wait for TOGGLE bit ready
return ReturnStatus;
}
/************************************************************************/
/* PROCEDURE: Erase_Entire_Chip */
/* */
/* This procedure can be used to erase the entire chip. */
/* */
/* Input: */
/* NONE */
/* */
/* Output: */
/* NONE */
/************************************************************************/
int Erase_Entire_Chip(void)
{
// Issue the Chip Erase command to 39VF0X
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x0080; // write data 0x0080 to device addr 0x555
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x0010; // write data 0x0010 to device addr 0x555
//Delay_50_Milli_Seconds(); // Delay Tsce time
if (Check_Data_Polling (0,0xFFFF))
return TRUE;
else
return FALSE;
}
/************************************************************************/
/* PROCEDURE: Program_One_Word
*/
/* */
/* This procedure can be used to program ONE word of data to the */
/* 39VF0X. */
/* */
/* 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 39VF0XB */
/* Dst DESTINATION address which will be written with the */
/* data passed in from Src */
/* */
/* Output: */
/* return TRUE: indicates success in word-program */
/* return FALSE: indicates failure in word-program */
/************************************************************************/
int Program_One_Word (WORD *SrcWord, Uint32 Dst)
{
Uint32 DestBuf = Dst;
WORD *SourceBuf = SrcWord;
int ReturnStatus;
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x00A0; // write data 0x00A0 to device addr 0x555
*sysAddress(DestBuf) = *SourceBuf; // transfer the WORD to destination
ReturnStatus = Check_Toggle_Ready(DestBuf); // wait for TOGGLE bit ready
return ReturnStatus;
}
/************************************************************************/
/* PROCEDURE: Program_One_Sector */
/* */
/* This procedure can be used to program a total of 2048 words of data */
/* to the SST39VF0X. */
/* */
/* NOTES: 1. It is necessary to first erase the sector before the*/
/* programming. */
/* 2. This sample code assumes the destination address passed*/
/* from the calling function is the starting address of the*/
/* sector.*/
/* */
/* Input: */
/* Src SOURCE address containing the data which will be */
/* written to the 39VF0XB */
/* Dst DESTINATION address which will be written with the */
/* data passed in from Src */
/*
*/
/* Output: */
/* return TRUE: indicates success in sector-program */
/* return FALSE: indicates failure in sector-program */
/************************************************************************/
int Program_One_Sector (WORD *Src, Uint32 Dst)
{
WORD *SourceBuf;
Uint32 DestBuf;
int Index, ReturnStatus;
SourceBuf = Src;
DestBuf = Dst;
ReturnStatus = Erase_One_Sector(DestBuf);// erase the sector first
if (!ReturnStatus)
return ReturnStatus;
for (Index = 0; Index < SECTOR_SIZE; Index++)
{ // transfer data from source to destination
ReturnStatus = Program_One_Word( SourceBuf, DestBuf);
++DestBuf;
++SourceBuf;
if (!ReturnStatus)
return ReturnStatus;
}
return ReturnStatus;
}
/************************************************************************/
/* PROCEDURE: Program_One_Block */
/* */
/* This procedure can be used to program a total of 32k words of data */
/* to the SST39VF0XB. */
/* */
/* NOTES: 1. It is necessary to first erase the block before the*/
/* programming. */
/* 2. This sample code assumes the destination address passed*/
/* from the calling function is the starting address of the*/
/* block.*/
/**/
/* Input: */
/* Src SOURCE address containing the data which will be */
/* written to the 39VF0X */
/* Dst DESTINATION address which will be written with the */
/* data passed in from Src */
/* */
/* Output: */
/* return TRUE: indicates success in block-program */
/* return FALSE: indicates failure in block-program */
/************************************************************************/
int Program_One_Block (WORD *Src, Uint32 Dst)
{
WORD *SourceBuf;
Uint32 DestBuf;
int Index, ReturnStatus;
SourceBuf = Src;
DestBuf = Dst;
ReturnStatus = Erase_One_Block(DestBuf);// erase the block first
if (!ReturnStatus)
return ReturnStatus;
for (Index = 0; Index < BLOCK_SIZE; Index++)
{ // transfer data from source to destination
ReturnStatus = Program_One_Word( SourceBuf, DestBuf);
++DestBuf;
++SourceBuf;
if (!ReturnStatus)
return ReturnStatus;
}
return ReturnStatus;
}
/************************************************************************/
/* PROCEDURE: SecID_Lock_Status */
/* */
/* This procedure should be used to check the Lock Status of SecID*/
/* */
/* Input: */
/* None */
/* */
/* Output: */
/* return TRUE: indicates SecID is Locked */
/* return FALSE: indicates SecID is Unlocked */
/************************************************************************/
int SecID_Lock_Status(void)
{
WORD SecID_Status;
// Issue the Sec ID Entry code to 39VF0X
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x0088; // write data 0x0088 to device addr 0x555
Delay_150_Nano_Seconds(); // insert delay time = Tida
// Read Lock Status of SecID segment
SecID_Status = *sysAddress(0x00FF);
SecID_Status &= 0x0008; // Unlocked: DQ3=1; Locked: DQ3=0
// Issue the Sec ID Exit code thus returning the 39VF0X
// to the read operating mode
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x00F0; // write data 0x00F0 to device addr 0x555
Delay_150_Nano_Seconds(); // insert delay time = Tida
if (!SecID_Status)
return TRUE; // SecID segment is Locked
return FALSE; // SecID segment is Unlocked
}
/************************************************************************/
/* PROCEDURE: User_SecID_Word_Program */
/* */
/* This procedure can be used to program data into the User SecID */
/* segment (from 000010H--000017H) in 39VF0XB. */
/* */
/* NOTE: 1. It's recommended to lock out the SecID segment after the */
/* completion of program.*/
/* 2. There's no way to unlock the SecID segment once it's*/
/* locked.*/
/* */
/* Input: */
/* SrcWordSource address to fetch data*/
/* Dst Destination address to write data*/
/* length number of word needs
to be programmed*/
/* */
/* Output: */
/* return TRUE: indicates SecID program is successful */
/* return FALSE: indicates SecID program is failed or SecID */
/* is locked.*/
/************************************************************************/
int User_SecID_Word_Program (WORD *SrcWord, WORD *Dst, int length)
{
WORD *DestBuf;
WORD *SourceBuf;
int test, index=length;
DestBuf = Dst;
SourceBuf = SrcWord;
test = SecID_Lock_Status (); // check whether the SecID is Locked or not
if (test) // TRUE: SecID is Locked
return FALSE;
while (index--)
{
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x00A5; // write data 0x00A5 to device addr 0x555
*sysAddress(DestBuf) = *SourceBuf; // transfer the WORD to destination
++DestBuf;
++SourceBuf;
// Read the toggle bit to detect end-of-write for the Sec ID.
// Do Not use Data# Polling for User_SecID_Word_Program.
test = Check_Toggle_Ready((Uint32)DestBuf); // wait for TOGGLE bit to get ready
if (!test)
return FALSE; // SecID Word-Program failed!
}
return TRUE;
}
/************************************************************************/
/* PROCEDURE: User_SecID_Lock_Out */
/* */
/* This procedure can be used to Lock Out the User Seccurity ID. */
/* User Security ID segment, from 000010H--000017H, in 39VF0XB. */
/* */
/* NOTE: 1. Call SecID_Lock_Status() first to verify the SecID is */
/* unlocked.*/
/* 2. SecID segment can't be erased.*/
/* 3. SecID segment can't be unlocked once it's locked.*/
/* */
/* Input: None */
/* */
/* Output: None */
/************************************************************************/
void User_SecID_Lock_Out (void)
{
*sysAddress(0x555) = 0x00AA; // write data 0x00AA to device addr 0x555
*sysAddress(0x2AA) = 0x0055; // write data 0x0055 to device addr 0x2AA
*sysAddress(0x555) = 0x0085; // write data 0x0085 to device addr 0x555
*sysAddress(0x00FF) = 0x0000; // write data 0x0000 to any addr
Delay_10_Micro_Seconds();// Wait for Word-Program timeout, Tbp=10us
}
/*************************************************************
***********/
/* PROCEDURE: Erase_Suspend */
/* */
/* This procedure can be used to temporarily suspend a Sector/Block-*/
/* Erase operation in 39VF0XB. */
/* */
/* Input: None */
/* */
/* Output: None */
/************************************************************************/
void Erase_Suspend (void)
{
*sysAddress(0x555) = 0x00B0; // write data 0x00B0 to any addr, i.e. 0x555
Delay_20_Micro_Seconds();// The device automatically enters read mode
// typically within 20 us after the Erase-Suspend command issued.
}
/************************************************************************/
/* PROCEDURE: Erase_Resume */
/* */
/* This procedure can be used to resume a Sector-Erase or Block-Erase */
/* operation that had been suspended in 39VF0XB. */
/* */
/* Input: None */
/* */
/* Output: None */
/************************************************************************/
void Erase_Resume (void)
{
*sysAddress(0x555) = 0x0030; // write data 0x0030 to any addr, i.e. 0x555
}
/************************************************************************/
/* 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: TRUE Data toggling success */
/* FALSE Time out */
/************************************************************************/
int Check_Toggle_Ready (Uint32 Dst)
{
WORD PreData;
WORD CurrData;
unsigned long TimeOut = 0;
Pre
Data = *sysAddress(Dst);
PreData = PreData & 0x0040; // read DQ6
while (TimeOut < MAX_TIMEOUT) // MAX_TIMEOUT=0x07FFFFFF
{
CurrData = *sysAddress(Dst);
CurrData = CurrData & 0x0040; // read DQ6 again
if (PreData == CurrData)
{
return TRUE;
}
PreData = CurrData;
TimeOut++;
}
return FALSE;
}
/************************************************************************/
/* 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: */
/* TRUE Data polling success */
/* FALSE Time out */
/************************************************************************/
int Check_Data_Polling (Uint32 Dst, WORD TrueData)
{
WORD CurrData;
unsigned long int TimeOut = 0;
TrueData = TrueData & 0x0080; // read D7
while (TimeOut < MAX_TIMEOUT)// MAX_TIMEOUT=0x07FFFFFF
{
CurrData = *sysAddress(Dst);
CurrData = CurrData & 0x0080; // read DQ7
if (TrueData == CurrData)
{
return TRUE;
}
TimeOut++;
}
return FALSE;
}
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