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今天是：2024年09月10日（星期二）
2018年09月10日 | 关于STM8S使用硬件SPI收发问题
2018-09-10 来源：eefocus
在调试STM8S的SPI时候,由于在学习板上飞线,然后发现每次读SPI FLASH的设备ID等都是不对的.
在21IC发帖求救http://bbs.21ic.com/forum.php?mod=viewthread&tid=788880&epclose=1
总体来说是怀疑硬件飞线的干扰.于是今天又飞了一块板子,发现仍然有这样的问题.
好吧,真的只能打板了.
自己想想会不会在读取数据前SPI的硬件BUFFER中就存在有数据啊.
嗯,有可能, 于是在读数据前,先将SPI的数据先读出,清空缓存,具体代码如下
/*
--Common functions
*/
/*
* Function: Wait_Flash_WarmUp
* Arguments: None.
* Description: Wait some time until flash read / write enable.
* Return Message: None.
*/
void Wait_Flash_WarmUp()
{
uint32 time_cnt = FlashFullAccessTime;
while( time_cnt > 0 )
{
time_cnt--;
}
}
/*
* Function: Initial_Spi
* Arguments: None
* Description: Initial spi flash state and wait flash warm-up
* (enable read/write).
* Return Message: None
*/
void Initial_Spi()
{
#ifdef GPIO_SPI
WPn = 1; // Write potected initial high
SI = 0; // Flash input data
SCLK = 1; // Flash input clock
CSn = 1; // Chip Select
#endif
GPIO_Init(CS_PIN,GPIO_MODE_OUT_PP_HIGH_FAST);
GPIO_Init(SPI_SCK_PIN,GPIO_MODE_OUT_PP_HIGH_FAST);
GPIO_Init(SPI_MOSI_PIN,GPIO_MODE_OUT_PP_HIGH_FAST);
GPIO_Init(SPI_MISO_PIN,GPIO_MODE_IN_PU_NO_IT);
SPI_DeInit();
SPI_Init(SPI_FIRSTBIT_MSB,SPI_BAUDRATEPRESCALER_2,SPI_MODE_MASTER,SPI_CLOCKPOLARITY_HIGH,\
SPI_CLOCKPHASE_2EDGE,SPI_DATADIRECTION_2LINES_FULLDUPLEX,SPI_NSS_SOFT,0x07);
SPI_Cmd(TRUE);
// Wait flash warm-up
Wait_Flash_WarmUp();
}
/*
* Function: CS_Low, CS_High
* Arguments: None.
* Description: Chip select go low / high.
* Return Message: None.
*/
void CS_Low()
{
#ifdef GPIO_SPI
CSn = 0;
#else
//--- insert your chip select code here. ---//
GPIO_WriteLow(CS_PIN);
#endif
}
void CS_High()
{
#ifdef GPIO_SPI
CSn = 1;
WPn = 1;
#else
//--- insert your chip select code here. ---//
GPIO_WriteHigh(CS_PIN);
#endif
}
/*
* Function: InsertDummyCycle
* Arguments: dummy_cycle, number of dummy clock cycle
* Description: Insert dummy cycle of SCLK
* Return Message: None.
*/
void InsertDummyCycle( uint8 dummy_cycle )
{
#ifdef GPIO_SPI
uint8 i;
for( i=0; i < dummy_cycle; i=i+1 )
{
SCLK = 0;
SCLK = 1;
}
#else
//--- insert your code here. ---//
uint8 i;
for( i=0; i < dummy_cycle / 8 ; i=i+1 )
{
SPI_SendData(DUMMY_BYTE);
}
#endif
}
/*
* Function: SendByte
* Arguments: byte_value, data transfer to flash
* transfer_type, select different type of I/O mode.
* Seven mode:
* SIO, single IO
* DIO, dual IO
* QIO, quad IO
* PIO, parallel
* DTSIO, double transfer rate SIO
* DTDIO, double transfer rate DIO
* DTQIO, double transfer rate QIO
* Description: Send one byte data to flash
* Return Message: None.
*/
void SendByte( uint8 byte_value, uint8 transfer_type )
{
while(SPI_GetFlagStatus(SPI_FLAG_TXE) == RESET);
SPI_SendData(byte_value);
#ifdef GPIO_SPI
uint16 i;
uint8 cycle_cnt;
switch( transfer_type )
{
#ifdef SIO
case SIO: // single I/O
cycle_cnt = 8;
for( i= 0; i < cycle_cnt; i++ )
{
if ( (byte_value & IO_MASK) == 0x80 ){
SI = 1;
}
else{
SI = 0;
}
SCLK = 0;
byte_value = byte_value << 1;
SCLK = 1;
}
break;
#endif
#ifdef DIO
case DIO: // dual I/O
cycle_cnt = 4;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
P1 = (( byte_value & 0xc0 ) >> 2) | (P1 & 0xcf);
byte_value = byte_value << 2;
SCLK = 1;
}
break;
#endif
#ifdef QIO
case QIO: // quad I/O
cycle_cnt = 2;
for( i= 0; i < cycle_cnt; i++ )
{
P1 = (byte_value & 0xf0); // CS# and SCLK must be zero at this phase
byte_value = byte_value << 4;
SCLK = 1;
}
break;
#endif
#ifdef PIO
case PIO: // Parallel I/O
SCLK = 0;
PO7 = ( (byte_value & IO_MASK) == IO_MASK )?1:0;
PO6 = ( (byte_value & 0x40) == 0x40 )?1:0;
P3 = (byte_value & 0x3f) | (P3 & 0xc0);
SCLK = 1;
break;
#endif
#ifdef DTSIO
case DTSIO: // Double transfer rate single I/O
cycle_cnt = 4;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
SI = ( (byte_value & IO_MASK) == IO_MASK )?1:0;
byte_value = byte_value << 1;
SCLK = 1;
SI = ( (byte_value & IO_MASK) == IO_MASK )?1:0;
byte_value = byte_value << 1;
}
break;
#endif
#ifdef DTDIO
case DTDIO: // Double transfer rate dual I/O
cycle_cnt = 2;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
P1 = (( byte_value & 0xc0 ) >> 2) | (P1 & 0xcf);
byte_value = byte_value << 2;
SCLK = 1;
P1 = (( byte_value & 0xc0 ) >> 2) | (P1 & 0xcf);
byte_value = byte_value << 2;
}
break;
#endif
#ifdef DTQIO
case DTQIO: // Double transfer rate quad I/O
SCLK = 0;
P1 = (byte_value & 0xf0);
SCLK = 1;
byte_value = byte_value << 4;
P1 = (byte_value & 0xf0); // CS# and SCLK must be zero at this phase
break;
#endif
default:
break;
}
#else
switch( transfer_type )
{
#ifdef SIO
case SIO: // Single I/O
//--- insert your code here for single IO transfer. ---//
break;
#endif
#ifdef DIO
case DIO: // Dual I/O
//--- insert your code here for dual IO transfer. ---//
break;
#endif
#ifdef QIO
case QIO: // Quad I/O
//--- insert your code here for quad IO transfer. ---//
break;
#endif
#ifdef PIO
case PIO: // Parallel I/O
//--- insert your code here for parallel IO transfer. ---//
break;
#endif
#ifdef DTSIO
case DTSIO: // Double transfer rate Single I/O
//--- insert your code here for DT single IO transfer. ---//
break;
#endif
#ifdef DTDIO
case DTDIO: // Double transfer rate Dual I/O
//--- insert your code here for DT dual IO transfer. ---//
break;
#endif
#ifdef DTQIO
case DTQIO: // Double transfer rate Quad I/O
//--- insert your code here for DT quad IO transfer. ---//
break;
#endif
default:
break;
}
#endif /* End of GPIO_SPI */
}
/*
* Function: GetByte
* Arguments: byte_value, data receive from flash
* transfer_type, select different type of I/O mode.
* Seven mode:
* SIO, single IO
* DIO, dual IO
* QIO, quad IO
* PIO, parallel IO
* DTSIO, double transfer rate SIO
* DTDIO, double transfer rate DIO
* DTQIO, double transfer rate QIO
* Description: Get one byte data to flash
* Return Message: 8 bit data
*/
uint8 GetByte( uint8 transfer_type )
{
uint8 data_buf;
data_buf = SPI_ReceiveData();//必须先读取一下,防止接收缓存中存有数据
SendByte( DUMMY_BYTE, SIO );
while(SPI_GetFlagStatus(SPI_FLAG_RXNE) == RESET);
data_buf = SPI_ReceiveData();
#ifdef GPIO_SPI
uint16 i;
uint8 cycle_cnt;
data_buf = 0;
cycle_cnt = 8 >> transfer_type;
switch( transfer_type )
{
#ifdef SIO
case SIO: // single I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SO = 1;
// End VIP 8051 GPIO
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
if ( SO == 1 ){
data_buf = (data_buf | (0x80 >> i));
}
SCLK = 1;
}
break;
#endif
#ifdef DIO
case DIO: // dual I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SIO0 = 1;
SIO1 = 1;
// End VIP 8051 GPIO
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
data_buf = data_buf << 2;
data_buf = ( data_buf | ((P1 & 0x30) >> 4 ) );
SCLK = 1;
}
break;
#endif
#ifdef QIO
case QIO: // quad I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SIO0 = 1;
SIO1 = 1;
SIO2 = 1;
SIO3 = 1;
// End VIP 8051 GPIO
SCLK = 0;
data_buf = P1 & 0xf0;
SCLK = 1;
SCLK = 0;
data_buf = ((P1 & 0xf0)>> 4)| data_buf;
SCLK = 1;
break;
#endif
#ifdef PIO
case PIO: // Parallel I/O
// Set VIP 8051 GPIO as input ( need pull to high )
PO7 = 1;
PO6 = 1;
PO5 = 1;
PO4 = 1;
PO3 = 1;
PO2 = 1;
PO1 = 1;
PO0 = 1;
// End VIP 8051 GPIO
SCLK = 0;
data_buf = (( P1 & 0x20 )<< 2) | ((P1 & 0x02 ) << 5) | (P3 & 0x3f );
SCLK = 1;
break;
#endif
#ifdef DTSIO
case DTSIO: // Double transfer rate Single I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SO = 1;
// End VIP 8051 GPIO
cycle_cnt = 4;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
if ( SO == 1 ){
data_buf = (data_buf | ( 0x80 >> (i*2) ));
}
SCLK = 1;
if ( SO == 1 ){
data_buf = (data_buf | (0x80 >> ((i*2) + 1) ));
}
}
break;
#endif
#ifdef DTDIO
case DTDIO: // Double transfer rate Dual I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SIO0 = 1;
SIO1 = 1;
// End VIP 8051 GPIO
cycle_cnt = 2;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
data_buf = data_buf << 2;
data_buf = ( data_buf | ( (P1 & 0x30) >> 4 ) );
SCLK = 1;
data_buf = data_buf << 2;
data_buf = ( data_buf | ( (P1 & 0x30) >> 4 ) );
}
break;
#endif
#ifdef DTQIO
case DTQIO: // DTR qual I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SIO0 = 1;
SIO1 = 1;
SIO2 = 1;
SIO3 = 1;
// End VIP 8051 GPIO
SCLK = 0;
data_buf = P1 & 0xf0;
SCLK = 1;
data_buf = ( (P1 & 0xf0) >> 4 )| data_buf;
break;
#endif
default:
break;
}
#else
switch( transfer_type )
{
#ifdef SIO
case SIO: // Single I/O
//--- insert your code here for single IO receive. ---//
break;
#endif
#ifdef DIO
case DIO: // Dual I/O
//--- insert your code here for dual IO receive. ---//
break;
#endif
#ifdef QIO
case QIO: // Quad I/O
//--- insert your code here for qual IO receive. ---//
break;
#endif
#ifdef PIO
case PIO: // Parallel I/O
//--- insert your code here for parallel IO receive. ---//
break;
#endif
#ifdef DTSIO
case DTSIO: // Double transfer rate Single I/O
//--- insert your code here for DT single IO receive. ---//
break;
#endif
#ifdef DTDIO
case DTDIO: // Double transfer rate Dual I/O
//--- insert your code here for DT dual IO receive. ---//
break;
#endif
#ifdef DTQIO
case DTQIO: // Double transfer rate Qual I/O
//--- insert your code here for DT quad IO receive. ---//
#endif
default:
break;
}
#endif /* End of GPIO_SPI */
return data_buf;
}
/*
* Function: WaitFlashReady
* Arguments: ExpectTime, expected time-out value of flash operations.
* No use at non-synchronous IO mode.
* Description: Synchronous IO:
* If flash is ready return TRUE.
* If flash is time-out return FALSE.
* Non-synchronous IO:
* Always return TRUE
* Return Message: TRUE, FALSE
*/
BOOL WaitFlashReady( uint32 ExpectTime )
{
#ifndef NON_SYNCHRONOUS_IO
uint32 temp = 0;
while( IsFlashBusy() )
{
if( temp > ExpectTime )
{
return FALSE;
}
temp = temp + 1;
}
return TRUE;
#else
return TRUE;
#endif
}
/*
* Function: WaitRYBYReady
* Arguments: ExpectTime, expected time-out value of flash operations.
* No use at non-synchronous IO mode.
* Description: Synchronous IO:
* If flash is ready return TRUE.
* If flash is time-out return FALSE.
* Non-synchronous IO:
* Always return TRUE
* Return Message: TRUE, FALSE
*/
BOOL WaitRYBYReady( uint32 ExpectTime )
{
#ifndef NON_SYNCHRONOUS_IO
uint32 temp = 0;
#ifdef GPIO_SPI
while( SO == 0 )
#else
// Insert your code for waiting RYBY (SO) pin ready
#endif
{
if( temp > ExpectTime )
{
return FALSE;
}
temp = temp + 1;
}
return TRUE;
#else
return TRUE;
#endif
}
/*
* Function: IsFlashBusy
* Arguments: None.
* Description: Check status register WIP bit.
* If WIP bit = 1: return TRUE ( Busy )
* = 0: return FALSE ( Ready ).
* Return Message: TRUE, FALSE
*/
BOOL IsFlashBusy( void )
{
uint8 gDataBuffer;
CMD_RDSR( &gDataBuffer );
if( (gDataBuffer & FLASH_WIP_MASK) == FLASH_WIP_MASK )
return TRUE;
else
return FALSE;
}
/*
* Function: IsFlashQIO
* Arguments: None.
* Description: If flash QE bit = 1: return TRUE
* = 0: return FALSE.
* Return Message: TRUE, FALSE
*/
BOOL IsFlashQIO( void )
{
#ifdef FLASH_NO_QE_BIT
return TRUE;
#else
uint8 gDataBuffer;
CMD_RDSR( &gDataBuffer );
if( (gDataBuffer & FLASH_QE_MASK) == FLASH_QE_MASK )
return TRUE;
else
return FALSE;
#endif
}
/*
* Function: IsFlash4Byte
* Arguments: None
* Description: Check flash address is 3-byte or 4-byte.
* If flash 4BYTE bit = 1: return TRUE
* = 0: return FALSE.
* Return Message: TRUE, FALSE
*/
BOOL IsFlash4Byte( void )
{
#ifdef FLASH_CMD_RDSCUR
#ifdef FLASH_4BYTE_ONLY
return TRUE;
#elif FLASH_3BYTE_ONLY
return FALSE;
#else
uint8 gDataBuffer;
CMD_RDSCUR( &gDataBuffer );
if( (gDataBuffer & FLASH_4BYTE_MASK) == FLASH_4BYTE_MASK )
return TRUE;
else
return FALSE;
#endif
#else
return FALSE;
#endif
}
/*
* Function: SendFlashAddr
* Arguments: flash_address, 32 bit flash memory address
* io_mode, I/O mode to transfer address
* addr_4byte_mode,
* Description: Send flash address with 3-byte or 4-byte mode.
* Return Message: None
*/
void SendFlashAddr( uint32 flash_address, uint8 io_mode, uint8 addr_4byte_mode )
{
/* Check flash is 3-byte or 4-byte mode.
4-byte mode: Send 4-byte address (A31-A0)
3-byte mode: Send 3-byte address (A23-A0) */
if( addr_4byte_mode == TRUE ){
SendByte( (flash_address >> 24), io_mode ); // A31-A24
}
/* A23-A0 */
SendByte( (flash_address >> 16), io_mode );
SendByte( (flash_address >> 8), io_mode );
SendByte( (flash_address), io_mode );
}
/*
* ID Command
*/
/*
* Function: CMD_RDID
* Arguments: Identification, 32 bit buffer to store id
* Description: The RDID instruction is to read the manufacturer ID
* of 1-byte and followed by Device ID of 2-byte.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RDID( uint32 *Identification )
{
uint32 temp;
uint8 gDataBuffer[3];
// Chip select go low to start a flash command
CS_Low();
// Send command
SendByte( FLASH_CMD_RDID, SIO );
// Get manufacturer identification, device identification
gDataBuffer[0] = GetByte( SIO );
gDataBuffer[1] = GetByte( SIO );
gDataBuffer[2] = GetByte( SIO );
// Chip select go high to end a command
CS_High();
// Store identification
temp = (u32)(gDataBuffer[0]);
temp = (u32)((temp << 8) | gDataBuffer[1]);
*Identification = (u32)((temp << 8) | gDataBuffer[2]);
return FlashOperationSuccess;
}
/*
* Function: CMD_RES
* Arguments: ElectricIdentification, 8 bit buffer to store electric id
* Description: The RES instruction is to read the Device
* electric identification of 1-byte.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RES( uint8 *ElectricIdentification )
{
// Chip select go low to start a flash command
CS_Low();
// Send flash command and insert dummy cycle
SendByte( FLASH_CMD_RES, SIO );
InsertDummyCycle( 24 );
// Get electric identification
*ElectricIdentification = GetByte( SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_REMS
* Arguments: REMS_Identification, 16 bit buffer to store id
* fsptr, pointer of flash status structure
* Description: The REMS instruction is to read the Device
* manufacturer ID and electric ID of 1-byte.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_REMS( uint16 *REMS_Identification, FlashStatus *fsptr )
{
uint8 gDataBuffer[2];
// Chip select go low to start a flash command
CS_Low();
// Send flash command and insert dummy cycle ( if need )
// ArrangeOpt = 0x00 will output the manufacturer's ID first
// = 0x01 will output electric ID first
SendByte( FLASH_CMD_REMS, SIO );
InsertDummyCycle( 16 );
SendByte( fsptr->ArrangeOpt, SIO );
// Get ID
gDataBuffer[0] = GetByte( SIO );
gDataBuffer[1] = GetByte( SIO );
// Store identification informaion
*REMS_Identification = (gDataBuffer[0] << 8) | gDataBuffer[1];
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Register Command
*/
/*
* Function: CMD_RDSR
* Arguments: StatusReg, 8 bit buffer to store status register value
* Description: The RDSR instruction is for reading Status Register Bits.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RDSR( uint8 *StatusReg )
{
uint8 gDataBuffer;
// Chip select go low to start a flash command
CS_Low();
// Send command
SendByte( FLASH_CMD_RDSR, SIO );
gDataBuffer = GetByte( SIO );
// Chip select go high to end a flash command
CS_High();
*StatusReg = gDataBuffer;
return FlashOperationSuccess;
}
/*
* Function: CMD_WRSR
* Arguments: UpdateValue, 8/16 bit status register value to updata
* Description: The WRSR instruction is for changing the values of
* Status Register Bits (and configuration register)
* Return Message: FlashIsBusy, FlashTimeOut, FlashOperationSuccess
*/
#ifdef SUPPORT_WRSR_CR
ReturnMsg CMD_WRSR( uint16 UpdateValue )
#else
ReturnMsg CMD_WRSR( uint8 UpdateValue )
#endif
{
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
// Send command and update value
SendByte( FLASH_CMD_WRSR, SIO );
SendByte( UpdateValue, SIO );
#ifdef SUPPORT_WRSR_CR
SendByte( UpdateValue >> 8, SIO ); // write configuration register
#endif
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( WriteStatusRegCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Function: CMD_RDSCUR
* Arguments: SecurityReg, 8 bit buffer to store security register value
* Description: The RDSCUR instruction is for reading the value of
* Security Register bits.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RDSCUR( uint8 *SecurityReg )
{
uint8 gDataBuffer;
// Chip select go low to start a flash command
CS_Low();
//Send command
SendByte( FLASH_CMD_RDSCUR, SIO );
gDataBuffer = GetByte( SIO );
// Chip select go high to end a flash command
CS_High();
*SecurityReg = gDataBuffer;
return FlashOperationSuccess;
}
/*
* Function: CMD_WRSCUR
* Arguments: None.
* Description: The WRSCUR instruction is for changing the values of
* Security Register Bits.
* Return Message: FlashIsBusy, FlashOperationSuccess, FlashWriteRegFailed,
* FlashTimeOut
*/
ReturnMsg CMD_WRSCUR( void )
{
uint8 gDataBuffer;
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
// Write WRSCUR command
SendByte( FLASH_CMD_WRSCUR, SIO );
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( WriteSecuRegCycleTime ) ){
CMD_RDSCUR( &gDataBuffer );
// Check security register LDSO bit
if( (gDataBuffer & FLASH_LDSO_MASK) == FLASH_LDSO_MASK )
return FlashOperationSuccess;
else
return FlashWriteRegFailed;
}
else
return FlashTimeOut;
}
/*
* Read Command
*/
/*
* Function: CMD_READ
* Arguments: flash_address, 32 bit flash memory address
* target_address, buffer address to store returned data
* byte_length, length of returned data in byte unit
* Description: The READ instruction is for reading data out.
* Return Message: FlashAddressInvalid, FlashOperationSuccess
*/
ReturnMsg CMD_READ( uint32 flash_address, uint8 *target_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Chip select go low to start a flash command
CS_Low();
// Write READ command and address
SendByte( FLASH_CMD_READ, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
// Set a loop to read data into buffer
for( index=0; index < byte_length; index++ )
{
// Read data one byte at a time
*(target_address + index) = GetByte( SIO );
}
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_DREAD
* Arguments: flash_address, 32 bit flash memory address
* target_address, buffer address to store returned data
* byte_length, length of returned data in byte unit
* Description: The DREAD instruction enable double throughput of Serial
* Flash in read mode
* Return Message: FlashAddressInvalid, FlashOperationSuccess
*/
ReturnMsg CMD_DREAD( uint32 flash_address, uint8 *target_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Chip select go low to start a flash command
CS_Low();
// Write 2-I/O Read command and address
SendByte( FLASH_CMD_DREAD, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
InsertDummyCycle( 8 ); // Wait 8 dummy cycle
// Set a loop to read data into data buffer
for( index=0; index < byte_length; index++ )
{
*(target_address + index) = GetByte( DIO );
}
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_FASTREAD
* Arguments: flash_address, 32 bit flash memory address
* target_address, buffer address to store returned data
* byte_length, length of returned data in byte unit
* Description: The FASTREAD instruction is for quickly reading data out.
* Return Message: FlashAddressInvalid, FlashOperationSuccess
*/
ReturnMsg CMD_FASTREAD( uint32 flash_address, uint8 *target_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Chip select go low to start a flash command
CS_Low();
// Write Fast Read command, address and dummy cycle
SendByte( FLASH_CMD_FASTREAD, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
InsertDummyCycle ( 8 ); // Wait dummy cycle
// Set a loop to read data into data buffer
for( index=0; index < byte_length; index++ )
{
*(target_address + index) = GetByte( SIO );
}
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_RDSFDP
* Arguments: flash_address, 32 bit flash memory address
* target_address, buffer address to store returned data
* byte_length, length of returned data in byte unit
* Description: RDSFDP can retrieve the operating characteristics, structure
* and vendor-specified information such as identifying information,
* memory size, operating voltages and timinginformation of device
* Return Message: FlashAddressInvalid, FlashOperationSuccess
*/
ReturnMsg CMD_RDSFDP( uint32 flash_address, uint8 *target_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Chip select go low to start a flash command
CS_Low();
// Write Read SFDP command
SendByte( FLASH_CMD_RDSFDP, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
InsertDummyCycle ( 8 ); // Insert dummy cycle
// Set a loop to read data into data buffer
for( index=0; index < byte_length; index++ )
{
*(target_address + index) = GetByte( SIO );
}
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Program Command
*/
/*
* Function: CMD_WREN
* Arguments: None.
* Description: The WREN instruction is for setting
* Write Enable Latch (WEL) bit.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_WREN( void )
{
// Chip select go low to start a flash command
CS_Low();
// Write Enable command = 0x06, Setting Write Enable Latch Bit
SendByte( FLASH_CMD_WREN, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_WRDI
* Arguments: None.
* Description: The WRDI instruction is to reset
* Write Enable Latch (WEL) bit.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_WRDI( void )
{
// Chip select go low to start a flash command
CS_Low();
// Write Disable command = 0x04, resets Write Enable Latch Bit
SendByte( FLASH_CMD_WRDI, SIO );
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_PP
* Arguments: flash_address, 32 bit flash memory address
* source_address, buffer address of source data to program
* byte_length, byte length of data to programm
* Description: The PP instruction is for programming
* the memory to be "0".
* The device only accept the last 256 byte ( or 32 byte ) to program.
* If the page address ( flash_address[7:0] ) reach 0xFF, it will
* program next at 0x00 of the same page.
* Some products have smaller page size ( 32 byte )
* Return Message: FlashAddressInvalid, FlashIsBusy, FlashOperationSuccess,
* FlashTimeOut
*/
ReturnMsg CMD_PP( uint32 flash_address, uint8 *source_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
// Write Page Program command
SendByte( FLASH_CMD_PP, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
// Set a loop to down load whole page data into flash's buffer
// Note: only last 256 byte ( or 32 byte ) will be programmed
for( index=0; index < byte_length; index++ )
{
SendByte( *(source_address + index), SIO );
}
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( PageProgramCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Erase Command
*/
/*
* Function: CMD_SE
* Arguments: flash_address, 32 bit flash memory address
* Description: The SE instruction is for erasing the data
* of the chosen sector (4KB) to be "1".
* Return Message: FlashAddressInvalid, FlashIsBusy, FlashOperationSuccess,
* FlashTimeOut
*/
ReturnMsg CMD_SE( uint32 flash_address )
{
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
//Write Sector Erase command = 0x20;
SendByte( FLASH_CMD_SE, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( SectorEraseCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Function: CMD_BE
* Arguments: flash_address, 32 bit flash memory address
* Description: The BE instruction is for erasing the data
* of the chosen sector (64KB) to be "1".
* Return Message: FlashAddressInvalid, FlashIsBusy, FlashOperationSuccess,
* FlashTimeOut
*/
ReturnMsg CMD_BE( uint32 flash_address )
{
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
//Write Block Erase command = 0xD8;
SendByte( FLASH_CMD_BE, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( BlockEraseCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Function: CMD_CE
* Arguments: None.
* Description: The CE instruction is for erasing the data
* of the whole chip to be "1".
* Return Message: FlashIsBusy, FlashOperationSuccess, FlashTimeOut
*/
ReturnMsg CMD_CE( void )
{
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
//Write Chip Erase command = 0x60;
SendByte( FLASH_CMD_CE, SIO );
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( ChipEraseCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Mode setting Command
*/
/*
* Function: CMD_DP
* Arguments: None.
* Description: The DP instruction is for setting the
* device on the minimizing the power consumption.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_DP( void )
{
// Chip select go low to start a flash command
CS_Low();
// Deep Power Down Mode command
SendByte( FLASH_CMD_DP, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_RDP
* Arguments: None.
* Description: The Release from RDP instruction is
* putting the device in the Stand-by Power mode.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RDP( void )
{
// Chip select go low to start a flash command
CS_Low();
// Deep Power Down Mode command
SendByte( FLASH_CMD_RDP, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_ENSO
* Arguments: None.
* Description: The ENSO instruction is for entering the secured OTP mode.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_ENSO( void )
{
// Chip select go low to start a flash command
CS_Low();
// Write ENSO command
SendByte( FLASH_CMD_ENSO, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_EXSO
* Arguments: None.
* Description: The EXSO instruction is for exiting the secured OTP mode.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_EXSO( void )
{
// Chip select go low to start a flash command
CS_Low();
// Write EXSO command = 0xC1
SendByte( FLASH_CMD_EXSO, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Reset setting Command
*/
/*
* Security Command
*/
注意在uint8 GetByte( uint8 transfer_type )函数的这句话
data_buf = SPI_ReceiveData();//必须先读取一下,防止接收缓存中存有数据
好了,调试一下,果然成功获取该SPI FLASH的值.
那我用IO方式验证一下.代码如下:
/*
--Common functions
*/
/*
* Function: Wait_Flash_WarmUp
* Arguments: None.
* Description: Wait some time until flash read / write enable.
* Return Message: None.
*/
void Wait_Flash_WarmUp()
{
uint32 time_cnt = FlashFullAccessTime;
while( time_cnt > 0 )
{
time_cnt--;
}
}
/*
* Function: Initial_Spi
* Arguments: None
* Description: Initial spi flash state and wait flash warm-up
* (enable read/write).
* Return Message: None
*/
void Initial_Spi()
{
#ifdef GPIO_SPI
WPn = 1; // Write potected initial high
SI = 0; // Flash input data
SCLK = 1; // Flash input clock
CSn = 1; // Chip Select
#endif
GPIO_Init(CS_PIN,GPIO_MODE_OUT_PP_HIGH_FAST);
GPIO_Init(SPI_SCK_PIN,GPIO_MODE_OUT_PP_HIGH_FAST);
GPIO_Init(SPI_MOSI_PIN,GPIO_MODE_OUT_PP_HIGH_FAST);
GPIO_Init(SPI_MISO_PIN,GPIO_MODE_IN_PU_NO_IT);
//SPI_DeInit();
//SPI_Init(SPI_FIRSTBIT_MSB,SPI_BAUDRATEPRESCALER_2,SPI_MODE_MASTER,SPI_CLOCKPOLARITY_HIGH,\
// SPI_CLOCKPHASE_2EDGE,SPI_DATADIRECTION_2LINES_FULLDUPLEX,SPI_NSS_SOFT,0x07);
//SPI_Cmd(TRUE);
// Wait flash warm-up
Wait_Flash_WarmUp();
}
/*
* Function: CS_Low, CS_High
* Arguments: None.
* Description: Chip select go low / high.
* Return Message: None.
*/
void CS_Low()
{
#ifdef GPIO_SPI
CSn = 0;
#else
//--- insert your chip select code here. ---//
GPIO_WriteLow(CS_PIN);
#endif
}
void CS_High()
{
#ifdef GPIO_SPI
CSn = 1;
WPn = 1;
#else
//--- insert your chip select code here. ---//
GPIO_WriteHigh(CS_PIN);
#endif
}
/*
* Function: InsertDummyCycle
* Arguments: dummy_cycle, number of dummy clock cycle
* Description: Insert dummy cycle of SCLK
* Return Message: None.
*/
void InsertDummyCycle( uint8 dummy_cycle )
{
#ifdef GPIO_SPI
uint8 i;
for( i=0; i < dummy_cycle; i=i+1 )
{
SCLK = 0;
SCLK = 1;
}
#else
//--- insert your code here. ---//
uint8 i;
#if 0
for( i=0; i < dummy_cycle / 8 ; i=i+1 )
{
SPI_SendData(DUMMY_BYTE);
}
#else
for( i=0; i < dummy_cycle; i=i+1 )
{
GPIO_WriteLow(SPI_SCK_PIN);
GPIO_WriteHigh(SPI_SCK_PIN);
}
#endif
#endif
}
/*
* Function: SendByte
* Arguments: byte_value, data transfer to flash
* transfer_type, select different type of I/O mode.
* Seven mode:
* SIO, single IO
* DIO, dual IO
* QIO, quad IO
* PIO, parallel
* DTSIO, double transfer rate SIO
* DTDIO, double transfer rate DIO
* DTQIO, double transfer rate QIO
* Description: Send one byte data to flash
* Return Message: None.
*/
void SendByte( uint8 byte_value, uint8 transfer_type )
{
uint16 i;
uint8 cycle_cnt;
#if 0
while(SPI_GetFlagStatus(SPI_FLAG_TXE) == RESET);
SPI_SendData(byte_value);
#else
cycle_cnt = 8;
for( i= 0; i < cycle_cnt; i++ )
{
if ( (byte_value & IO_MASK) == 0x80 ){
GPIO_WriteHigh(SPI_MOSI_PIN);
}
else{
GPIO_WriteLow(SPI_MOSI_PIN);
}
GPIO_WriteLow(SPI_SCK_PIN);
byte_value = byte_value << 1;
GPIO_WriteHigh(SPI_SCK_PIN);
}
#endif
#ifdef GPIO_SPI
switch( transfer_type )
{
#ifdef SIO
case SIO: // single I/O
cycle_cnt = 8;
for( i= 0; i < cycle_cnt; i++ )
{
if ( (byte_value & IO_MASK) == 0x80 ){
SI = 1;
}
else{
SI = 0;
}
SCLK = 0;
byte_value = byte_value << 1;
SCLK = 1;
}
break;
#endif
#ifdef DIO
case DIO: // dual I/O
cycle_cnt = 4;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
P1 = (( byte_value & 0xc0 ) >> 2) | (P1 & 0xcf);
byte_value = byte_value << 2;
SCLK = 1;
}
break;
#endif
#ifdef QIO
case QIO: // quad I/O
cycle_cnt = 2;
for( i= 0; i < cycle_cnt; i++ )
{
P1 = (byte_value & 0xf0); // CS# and SCLK must be zero at this phase
byte_value = byte_value << 4;
SCLK = 1;
}
break;
#endif
#ifdef PIO
case PIO: // Parallel I/O
SCLK = 0;
PO7 = ( (byte_value & IO_MASK) == IO_MASK )?1:0;
PO6 = ( (byte_value & 0x40) == 0x40 )?1:0;
P3 = (byte_value & 0x3f) | (P3 & 0xc0);
SCLK = 1;
break;
#endif
#ifdef DTSIO
case DTSIO: // Double transfer rate single I/O
cycle_cnt = 4;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
SI = ( (byte_value & IO_MASK) == IO_MASK )?1:0;
byte_value = byte_value << 1;
SCLK = 1;
SI = ( (byte_value & IO_MASK) == IO_MASK )?1:0;
byte_value = byte_value << 1;
}
break;
#endif
#ifdef DTDIO
case DTDIO: // Double transfer rate dual I/O
cycle_cnt = 2;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
P1 = (( byte_value & 0xc0 ) >> 2) | (P1 & 0xcf);
byte_value = byte_value << 2;
SCLK = 1;
P1 = (( byte_value & 0xc0 ) >> 2) | (P1 & 0xcf);
byte_value = byte_value << 2;
}
break;
#endif
#ifdef DTQIO
case DTQIO: // Double transfer rate quad I/O
SCLK = 0;
P1 = (byte_value & 0xf0);
SCLK = 1;
byte_value = byte_value << 4;
P1 = (byte_value & 0xf0); // CS# and SCLK must be zero at this phase
break;
#endif
default:
break;
}
#else
switch( transfer_type )
{
#ifdef SIO
case SIO: // Single I/O
//--- insert your code here for single IO transfer. ---//
break;
#endif
#ifdef DIO
case DIO: // Dual I/O
//--- insert your code here for dual IO transfer. ---//
break;
#endif
#ifdef QIO
case QIO: // Quad I/O
//--- insert your code here for quad IO transfer. ---//
break;
#endif
#ifdef PIO
case PIO: // Parallel I/O
//--- insert your code here for parallel IO transfer. ---//
break;
#endif
#ifdef DTSIO
case DTSIO: // Double transfer rate Single I/O
//--- insert your code here for DT single IO transfer. ---//
break;
#endif
#ifdef DTDIO
case DTDIO: // Double transfer rate Dual I/O
//--- insert your code here for DT dual IO transfer. ---//
break;
#endif
#ifdef DTQIO
case DTQIO: // Double transfer rate Quad I/O
//--- insert your code here for DT quad IO transfer. ---//
break;
#endif
default:
break;
}
#endif /* End of GPIO_SPI */
}
/*
* Function: GetByte
* Arguments: byte_value, data receive from flash
* transfer_type, select different type of I/O mode.
* Seven mode:
* SIO, single IO
* DIO, dual IO
* QIO, quad IO
* PIO, parallel IO
* DTSIO, double transfer rate SIO
* DTDIO, double transfer rate DIO
* DTQIO, double transfer rate QIO
* Description: Get one byte data to flash
* Return Message: 8 bit data
*/
uint8 GetByte( uint8 transfer_type )
{
uint8 data_buf;
uint16 i;
uint8 cycle_cnt;
data_buf = 0;
#if 0
data_buf = SPI_ReceiveData();
SendByte( DUMMY_BYTE, SIO );
while(SPI_GetFlagStatus(SPI_FLAG_RXNE) == RESET);
data_buf = SPI_ReceiveData();
#else
cycle_cnt = 8;
for( i= 0; i < cycle_cnt; i++ )
{
GPIO_WriteLow(SPI_SCK_PIN);
if ( GPIO_ReadInputPin(SPI_MISO_PIN) == 1 ){
data_buf = (data_buf | (0x80 >> i));
}
GPIO_WriteHigh(SPI_SCK_PIN);
}
#endif
#ifdef GPIO_SPI
cycle_cnt = 8 >> transfer_type;
switch( transfer_type )
{
#ifdef SIO
case SIO: // single I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SO = 1;
// End VIP 8051 GPIO
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
if ( SO == 1 ){
data_buf = (data_buf | (0x80 >> i));
}
SCLK = 1;
}
break;
#endif
#ifdef DIO
case DIO: // dual I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SIO0 = 1;
SIO1 = 1;
// End VIP 8051 GPIO
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
data_buf = data_buf << 2;
data_buf = ( data_buf | ((P1 & 0x30) >> 4 ) );
SCLK = 1;
}
break;
#endif
#ifdef QIO
case QIO: // quad I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SIO0 = 1;
SIO1 = 1;
SIO2 = 1;
SIO3 = 1;
// End VIP 8051 GPIO
SCLK = 0;
data_buf = P1 & 0xf0;
SCLK = 1;
SCLK = 0;
data_buf = ((P1 & 0xf0)>> 4)| data_buf;
SCLK = 1;
break;
#endif
#ifdef PIO
case PIO: // Parallel I/O
// Set VIP 8051 GPIO as input ( need pull to high )
PO7 = 1;
PO6 = 1;
PO5 = 1;
PO4 = 1;
PO3 = 1;
PO2 = 1;
PO1 = 1;
PO0 = 1;
// End VIP 8051 GPIO
SCLK = 0;
data_buf = (( P1 & 0x20 )<< 2) | ((P1 & 0x02 ) << 5) | (P3 & 0x3f );
SCLK = 1;
break;
#endif
#ifdef DTSIO
case DTSIO: // Double transfer rate Single I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SO = 1;
// End VIP 8051 GPIO
cycle_cnt = 4;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
if ( SO == 1 ){
data_buf = (data_buf | ( 0x80 >> (i*2) ));
}
SCLK = 1;
if ( SO == 1 ){
data_buf = (data_buf | (0x80 >> ((i*2) + 1) ));
}
}
break;
#endif
#ifdef DTDIO
case DTDIO: // Double transfer rate Dual I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SIO0 = 1;
SIO1 = 1;
// End VIP 8051 GPIO
cycle_cnt = 2;
for( i= 0; i < cycle_cnt; i++ )
{
SCLK = 0;
data_buf = data_buf << 2;
data_buf = ( data_buf | ( (P1 & 0x30) >> 4 ) );
SCLK = 1;
data_buf = data_buf << 2;
data_buf = ( data_buf | ( (P1 & 0x30) >> 4 ) );
}
break;
#endif
#ifdef DTQIO
case DTQIO: // DTR qual I/O
// Set VIP 8051 GPIO as input ( need pull to high )
SIO0 = 1;
SIO1 = 1;
SIO2 = 1;
SIO3 = 1;
// End VIP 8051 GPIO
SCLK = 0;
data_buf = P1 & 0xf0;
SCLK = 1;
data_buf = ( (P1 & 0xf0) >> 4 )| data_buf;
break;
#endif
default:
break;
}
#else
switch( transfer_type )
{
#ifdef SIO
case SIO: // Single I/O
//--- insert your code here for single IO receive. ---//
break;
#endif
#ifdef DIO
case DIO: // Dual I/O
//--- insert your code here for dual IO receive. ---//
break;
#endif
#ifdef QIO
case QIO: // Quad I/O
//--- insert your code here for qual IO receive. ---//
break;
#endif
#ifdef PIO
case PIO: // Parallel I/O
//--- insert your code here for parallel IO receive. ---//
break;
#endif
#ifdef DTSIO
case DTSIO: // Double transfer rate Single I/O
//--- insert your code here for DT single IO receive. ---//
break;
#endif
#ifdef DTDIO
case DTDIO: // Double transfer rate Dual I/O
//--- insert your code here for DT dual IO receive. ---//
break;
#endif
#ifdef DTQIO
case DTQIO: // Double transfer rate Qual I/O
//--- insert your code here for DT quad IO receive. ---//
#endif
default:
break;
}
#endif /* End of GPIO_SPI */
return data_buf;
}
/*
* Function: WaitFlashReady
* Arguments: ExpectTime, expected time-out value of flash operations.
* No use at non-synchronous IO mode.
* Description: Synchronous IO:
* If flash is ready return TRUE.
* If flash is time-out return FALSE.
* Non-synchronous IO:
* Always return TRUE
* Return Message: TRUE, FALSE
*/
BOOL WaitFlashReady( uint32 ExpectTime )
{
#ifndef NON_SYNCHRONOUS_IO
uint32 temp = 0;
while( IsFlashBusy() )
{
if( temp > ExpectTime )
{
return FALSE;
}
temp = temp + 1;
}
return TRUE;
#else
return TRUE;
#endif
}
/*
* Function: WaitRYBYReady
* Arguments: ExpectTime, expected time-out value of flash operations.
* No use at non-synchronous IO mode.
* Description: Synchronous IO:
* If flash is ready return TRUE.
* If flash is time-out return FALSE.
* Non-synchronous IO:
* Always return TRUE
* Return Message: TRUE, FALSE
*/
BOOL WaitRYBYReady( uint32 ExpectTime )
{
#ifndef NON_SYNCHRONOUS_IO
uint32 temp = 0;
#ifdef GPIO_SPI
while( SO == 0 )
#else
// Insert your code for waiting RYBY (SO) pin ready
#endif
{
if( temp > ExpectTime )
{
return FALSE;
}
temp = temp + 1;
}
return TRUE;
#else
return TRUE;
#endif
}
/*
* Function: IsFlashBusy
* Arguments: None.
* Description: Check status register WIP bit.
* If WIP bit = 1: return TRUE ( Busy )
* = 0: return FALSE ( Ready ).
* Return Message: TRUE, FALSE
*/
BOOL IsFlashBusy( void )
{
uint8 gDataBuffer;
CMD_RDSR( &gDataBuffer );
if( (gDataBuffer & FLASH_WIP_MASK) == FLASH_WIP_MASK )
return TRUE;
else
return FALSE;
}
/*
* Function: IsFlashQIO
* Arguments: None.
* Description: If flash QE bit = 1: return TRUE
* = 0: return FALSE.
* Return Message: TRUE, FALSE
*/
BOOL IsFlashQIO( void )
{
#ifdef FLASH_NO_QE_BIT
return TRUE;
#else
uint8 gDataBuffer;
CMD_RDSR( &gDataBuffer );
if( (gDataBuffer & FLASH_QE_MASK) == FLASH_QE_MASK )
return TRUE;
else
return FALSE;
#endif
}
/*
* Function: IsFlash4Byte
* Arguments: None
* Description: Check flash address is 3-byte or 4-byte.
* If flash 4BYTE bit = 1: return TRUE
* = 0: return FALSE.
* Return Message: TRUE, FALSE
*/
BOOL IsFlash4Byte( void )
{
#ifdef FLASH_CMD_RDSCUR
#ifdef FLASH_4BYTE_ONLY
return TRUE;
#elif FLASH_3BYTE_ONLY
return FALSE;
#else
uint8 gDataBuffer;
CMD_RDSCUR( &gDataBuffer );
if( (gDataBuffer & FLASH_4BYTE_MASK) == FLASH_4BYTE_MASK )
return TRUE;
else
return FALSE;
#endif
#else
return FALSE;
#endif
}
/*
* Function: SendFlashAddr
* Arguments: flash_address, 32 bit flash memory address
* io_mode, I/O mode to transfer address
* addr_4byte_mode,
* Description: Send flash address with 3-byte or 4-byte mode.
* Return Message: None
*/
void SendFlashAddr( uint32 flash_address, uint8 io_mode, uint8 addr_4byte_mode )
{
/* Check flash is 3-byte or 4-byte mode.
4-byte mode: Send 4-byte address (A31-A0)
3-byte mode: Send 3-byte address (A23-A0) */
if( addr_4byte_mode == TRUE ){
SendByte( (flash_address >> 24), io_mode ); // A31-A24
}
/* A23-A0 */
SendByte( (flash_address >> 16), io_mode );
SendByte( (flash_address >> 8), io_mode );
SendByte( (flash_address), io_mode );
}
/*
* ID Command
*/
/*
* Function: CMD_RDID
* Arguments: Identification, 32 bit buffer to store id
* Description: The RDID instruction is to read the manufacturer ID
* of 1-byte and followed by Device ID of 2-byte.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RDID( uint32 *Identification )
{
uint32 temp;
uint8 gDataBuffer[3];
// Chip select go low to start a flash command
CS_Low();
// Send command
SendByte( FLASH_CMD_RDID, SIO );
// Get manufacturer identification, device identification
gDataBuffer[0] = GetByte( SIO );
gDataBuffer[1] = GetByte( SIO );
gDataBuffer[2] = GetByte( SIO );
// Chip select go high to end a command
CS_High();
// Store identification
temp = (u32)(gDataBuffer[0]);
temp = (u32)((temp << 8) | gDataBuffer[1]);
*Identification = (u32)((temp << 8) | gDataBuffer[2]);
return FlashOperationSuccess;
}
/*
* Function: CMD_RES
* Arguments: ElectricIdentification, 8 bit buffer to store electric id
* Description: The RES instruction is to read the Device
* electric identification of 1-byte.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RES( uint8 *ElectricIdentification )
{
// Chip select go low to start a flash command
CS_Low();
// Send flash command and insert dummy cycle
SendByte( FLASH_CMD_RES, SIO );
InsertDummyCycle( 24 );
// Get electric identification
*ElectricIdentification = GetByte( SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_REMS
* Arguments: REMS_Identification, 16 bit buffer to store id
* fsptr, pointer of flash status structure
* Description: The REMS instruction is to read the Device
* manufacturer ID and electric ID of 1-byte.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_REMS( uint16 *REMS_Identification, FlashStatus *fsptr )
{
uint8 gDataBuffer[2];
// Chip select go low to start a flash command
CS_Low();
// Send flash command and insert dummy cycle ( if need )
// ArrangeOpt = 0x00 will output the manufacturer's ID first
// = 0x01 will output electric ID first
SendByte( FLASH_CMD_REMS, SIO );
InsertDummyCycle( 16 );
SendByte( fsptr->ArrangeOpt, SIO );
// Get ID
gDataBuffer[0] = GetByte( SIO );
gDataBuffer[1] = GetByte( SIO );
// Store identification informaion
*REMS_Identification = (gDataBuffer[0] << 8) | gDataBuffer[1];
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Register Command
*/
/*
* Function: CMD_RDSR
* Arguments: StatusReg, 8 bit buffer to store status register value
* Description: The RDSR instruction is for reading Status Register Bits.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RDSR( uint8 *StatusReg )
{
uint8 gDataBuffer;
// Chip select go low to start a flash command
CS_Low();
// Send command
SendByte( FLASH_CMD_RDSR, SIO );
gDataBuffer = GetByte( SIO );
// Chip select go high to end a flash command
CS_High();
*StatusReg = gDataBuffer;
return FlashOperationSuccess;
}
/*
* Function: CMD_WRSR
* Arguments: UpdateValue, 8/16 bit status register value to updata
* Description: The WRSR instruction is for changing the values of
* Status Register Bits (and configuration register)
* Return Message: FlashIsBusy, FlashTimeOut, FlashOperationSuccess
*/
#ifdef SUPPORT_WRSR_CR
ReturnMsg CMD_WRSR( uint16 UpdateValue )
#else
ReturnMsg CMD_WRSR( uint8 UpdateValue )
#endif
{
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
// Send command and update value
SendByte( FLASH_CMD_WRSR, SIO );
SendByte( UpdateValue, SIO );
#ifdef SUPPORT_WRSR_CR
SendByte( UpdateValue >> 8, SIO ); // write configuration register
#endif
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( WriteStatusRegCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Function: CMD_RDSCUR
* Arguments: SecurityReg, 8 bit buffer to store security register value
* Description: The RDSCUR instruction is for reading the value of
* Security Register bits.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RDSCUR( uint8 *SecurityReg )
{
uint8 gDataBuffer;
// Chip select go low to start a flash command
CS_Low();
//Send command
SendByte( FLASH_CMD_RDSCUR, SIO );
gDataBuffer = GetByte( SIO );
// Chip select go high to end a flash command
CS_High();
*SecurityReg = gDataBuffer;
return FlashOperationSuccess;
}
/*
* Function: CMD_WRSCUR
* Arguments: None.
* Description: The WRSCUR instruction is for changing the values of
* Security Register Bits.
* Return Message: FlashIsBusy, FlashOperationSuccess, FlashWriteRegFailed,
* FlashTimeOut
*/
ReturnMsg CMD_WRSCUR( void )
{
uint8 gDataBuffer;
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
// Write WRSCUR command
SendByte( FLASH_CMD_WRSCUR, SIO );
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( WriteSecuRegCycleTime ) ){
CMD_RDSCUR( &gDataBuffer );
// Check security register LDSO bit
if( (gDataBuffer & FLASH_LDSO_MASK) == FLASH_LDSO_MASK )
return FlashOperationSuccess;
else
return FlashWriteRegFailed;
}
else
return FlashTimeOut;
}
/*
* Read Command
*/
/*
* Function: CMD_READ
* Arguments: flash_address, 32 bit flash memory address
* target_address, buffer address to store returned data
* byte_length, length of returned data in byte unit
* Description: The READ instruction is for reading data out.
* Return Message: FlashAddressInvalid, FlashOperationSuccess
*/
ReturnMsg CMD_READ( uint32 flash_address, uint8 *target_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Chip select go low to start a flash command
CS_Low();
// Write READ command and address
SendByte( FLASH_CMD_READ, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
// Set a loop to read data into buffer
for( index=0; index < byte_length; index++ )
{
// Read data one byte at a time
*(target_address + index) = GetByte( SIO );
}
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_DREAD
* Arguments: flash_address, 32 bit flash memory address
* target_address, buffer address to store returned data
* byte_length, length of returned data in byte unit
* Description: The DREAD instruction enable double throughput of Serial
* Flash in read mode
* Return Message: FlashAddressInvalid, FlashOperationSuccess
*/
ReturnMsg CMD_DREAD( uint32 flash_address, uint8 *target_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Chip select go low to start a flash command
CS_Low();
// Write 2-I/O Read command and address
SendByte( FLASH_CMD_DREAD, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
InsertDummyCycle( 8 ); // Wait 8 dummy cycle
// Set a loop to read data into data buffer
for( index=0; index < byte_length; index++ )
{
*(target_address + index) = GetByte( DIO );
}
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_FASTREAD
* Arguments: flash_address, 32 bit flash memory address
* target_address, buffer address to store returned data
* byte_length, length of returned data in byte unit
* Description: The FASTREAD instruction is for quickly reading data out.
* Return Message: FlashAddressInvalid, FlashOperationSuccess
*/
ReturnMsg CMD_FASTREAD( uint32 flash_address, uint8 *target_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Chip select go low to start a flash command
CS_Low();
// Write Fast Read command, address and dummy cycle
SendByte( FLASH_CMD_FASTREAD, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
InsertDummyCycle ( 8 ); // Wait dummy cycle
// Set a loop to read data into data buffer
for( index=0; index < byte_length; index++ )
{
*(target_address + index) = GetByte( SIO );
}
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_RDSFDP
* Arguments: flash_address, 32 bit flash memory address
* target_address, buffer address to store returned data
* byte_length, length of returned data in byte unit
* Description: RDSFDP can retrieve the operating characteristics, structure
* and vendor-specified information such as identifying information,
* memory size, operating voltages and timinginformation of device
* Return Message: FlashAddressInvalid, FlashOperationSuccess
*/
ReturnMsg CMD_RDSFDP( uint32 flash_address, uint8 *target_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Chip select go low to start a flash command
CS_Low();
// Write Read SFDP command
SendByte( FLASH_CMD_RDSFDP, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
InsertDummyCycle ( 8 ); // Insert dummy cycle
// Set a loop to read data into data buffer
for( index=0; index < byte_length; index++ )
{
*(target_address + index) = GetByte( SIO );
}
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Program Command
*/
/*
* Function: CMD_WREN
* Arguments: None.
* Description: The WREN instruction is for setting
* Write Enable Latch (WEL) bit.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_WREN( void )
{
// Chip select go low to start a flash command
CS_Low();
// Write Enable command = 0x06, Setting Write Enable Latch Bit
SendByte( FLASH_CMD_WREN, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_WRDI
* Arguments: None.
* Description: The WRDI instruction is to reset
* Write Enable Latch (WEL) bit.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_WRDI( void )
{
// Chip select go low to start a flash command
CS_Low();
// Write Disable command = 0x04, resets Write Enable Latch Bit
SendByte( FLASH_CMD_WRDI, SIO );
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_PP
* Arguments: flash_address, 32 bit flash memory address
* source_address, buffer address of source data to program
* byte_length, byte length of data to programm
* Description: The PP instruction is for programming
* the memory to be "0".
* The device only accept the last 256 byte ( or 32 byte ) to program.
* If the page address ( flash_address[7:0] ) reach 0xFF, it will
* program next at 0x00 of the same page.
* Some products have smaller page size ( 32 byte )
* Return Message: FlashAddressInvalid, FlashIsBusy, FlashOperationSuccess,
* FlashTimeOut
*/
ReturnMsg CMD_PP( uint32 flash_address, uint8 *source_address, uint32 byte_length )
{
uint32 index;
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
// Write Page Program command
SendByte( FLASH_CMD_PP, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
// Set a loop to down load whole page data into flash's buffer
// Note: only last 256 byte ( or 32 byte ) will be programmed
for( index=0; index < byte_length; index++ )
{
SendByte( *(source_address + index), SIO );
}
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( PageProgramCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Erase Command
*/
/*
* Function: CMD_SE
* Arguments: flash_address, 32 bit flash memory address
* Description: The SE instruction is for erasing the data
* of the chosen sector (4KB) to be "1".
* Return Message: FlashAddressInvalid, FlashIsBusy, FlashOperationSuccess,
* FlashTimeOut
*/
ReturnMsg CMD_SE( uint32 flash_address )
{
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
//Write Sector Erase command = 0x20;
SendByte( FLASH_CMD_SE, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( SectorEraseCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Function: CMD_BE
* Arguments: flash_address, 32 bit flash memory address
* Description: The BE instruction is for erasing the data
* of the chosen sector (64KB) to be "1".
* Return Message: FlashAddressInvalid, FlashIsBusy, FlashOperationSuccess,
* FlashTimeOut
*/
ReturnMsg CMD_BE( uint32 flash_address )
{
uint8 addr_4byte_mode;
// Check flash address
if( flash_address > FlashSize ) return FlashAddressInvalid;
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Check 3-byte or 4-byte mode
if( IsFlash4Byte() )
addr_4byte_mode = TRUE; // 4-byte mode
else
addr_4byte_mode = FALSE; // 3-byte mode
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
//Write Block Erase command = 0xD8;
SendByte( FLASH_CMD_BE, SIO );
SendFlashAddr( flash_address, SIO, addr_4byte_mode );
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( BlockEraseCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Function: CMD_CE
* Arguments: None.
* Description: The CE instruction is for erasing the data
* of the whole chip to be "1".
* Return Message: FlashIsBusy, FlashOperationSuccess, FlashTimeOut
*/
ReturnMsg CMD_CE( void )
{
// Check flash is busy or not
if( IsFlashBusy() ) return FlashIsBusy;
// Setting Write Enable Latch bit
CMD_WREN();
// Chip select go low to start a flash command
CS_Low();
//Write Chip Erase command = 0x60;
SendByte( FLASH_CMD_CE, SIO );
// Chip select go high to end a flash command
CS_High();
if( WaitFlashReady( ChipEraseCycleTime ) )
return FlashOperationSuccess;
else
return FlashTimeOut;
}
/*
* Mode setting Command
*/
/*
* Function: CMD_DP
* Arguments: None.
* Description: The DP instruction is for setting the
* device on the minimizing the power consumption.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_DP( void )
{
// Chip select go low to start a flash command
CS_Low();
// Deep Power Down Mode command
SendByte( FLASH_CMD_DP, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_RDP
* Arguments: None.
* Description: The Release from RDP instruction is
* putting the device in the Stand-by Power mode.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_RDP( void )
{
// Chip select go low to start a flash command
CS_Low();
// Deep Power Down Mode command
SendByte( FLASH_CMD_RDP, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_ENSO
* Arguments: None.
* Description: The ENSO instruction is for entering the secured OTP mode.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_ENSO( void )
{
// Chip select go low to start a flash command
CS_Low();
// Write ENSO command
SendByte( FLASH_CMD_ENSO, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Function: CMD_EXSO
* Arguments: None.
* Description: The EXSO instruction is for exiting the secured OTP mode.
* Return Message: FlashOperationSuccess
*/
ReturnMsg CMD_EXSO( void )
{
// Chip select go low to start a flash command
CS_Low();
// Write EXSO command = 0xC1
SendByte( FLASH_CMD_EXSO, SIO );
// Chip select go high to end a flash command
CS_High();
return FlashOperationSuccess;
}
/*
* Reset setting Command
*/
/*
* Security Command
*/
验证结果也正确的.
史海拾趣
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