AT45DB081D serial EEPROM code not working ( uC LM3s5951 is used)

Dhanush Nair

I am using AT45DB081D atmel IC and lm3s5951 stallaries controller
My code is working with GPIO but not with SPI my SPI code is as shown bellow:-

#define SSI_CLK       GPIO_PIN_0
#define SSI_CS        GPIO_PIN_1
#define SSI_TX        GPIO_PIN_3
#define SSI_RX        GPIO_PIN_2 

unsigned long data; 
int main(void){
  
    unsigned long BufReception;
  
    SysCtlClockSet(SYSCTL_SYSDIV_4 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN |
                   SYSCTL_XTAL_8MHZ);
    
    SysCtlPeripheralEnable(SYSCTL_PERIPH_SSI1);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE);  

    GPIOPinTypeGPIOOutPut(GPIO_PORTA_BASE, SSI_CS);
    GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, SSI_CS);
    GPIOPinTypeSSI(GPIO_PORTA_BASE, SSI_CLK | SSI_TX | SSI_RX );

    SSIConfigSetExpClk(SSI0_BASE, SysCtlClockGet(), SSI_FRF_MOTO_MODE_0, 
                       SSI_MODE_MASTER, 1000000, 8);
    
    SSIEnable(SSI0_BASE);
 DelayUs(10); //10uSec
 Spi_erase();
 Buffer_write(); // buffer 1 write
 Buffer_read(); // buffer 1 read
 LcdDisplay(data);//lcd display
 
 }

void Spi_erase()
{ 
 uint16 block_counter = 0;
 unit8 addfld[2];

Df_ReadyBusy(); while(block_counter<512) //total 512 block { addfld[0]=((uint8)(block_counter>>4)); addfld[1]=((uint8)(block_counter<<4)); GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, 0); //chip select low SSIDataPut(SSI0_BASE, 0x50); //block erase SSIDataGet(SSI0_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI0_BASE, &addfld[0]); SSIDataGet(SSI0_BASE, &dummyBuf); SSIDataPut(SSI0_BASE, &addfld[0]); //24 bits address SSIDataGet(SSI0_BASE, &dummyBuf); SSIDataPut(SSI0_BASE, 0x00); SSIDataGet(SSI0_BASE, &dummyBuf);

GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, SSI_CS);//chip select high Df_ReadyBusy(); }

}

void buffer_read()
{ 
     Df_ReadyBusy();
     GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, 0);  //chip select low
    SSIDataPut(SSI0_BASE, 0xD4);  //read buffer 1

SSIDataGet(SSI0_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI0_BASE, 0x00); SSIDataGet(SSI0_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI0_BASE, 0x00); //24 bits address SSIDataGet(SSI0_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI0_BASE, 0x00); SSIDataGet(SSI0_BASE, &dummyBuf);//dummy to clear write buffer

SSIDataPut(SSI0_BASE, 0x00);

SSIDataGet(SSI0_BASE, &data);//read data in 'data'

GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, SSI_CS);//chip select high

}

void buffer_write()
{ 
     Df_ReadyBusy();
     GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, 0);  //chip select low
    SSIDataPut(SSI0_BASE, 0x84);  //read buffer 1

SSIDataGet(SSI0_BASE, 0x41); // 'A' character

GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, SSI_CS);//chip select high

}

void  Df_ReadyBusy()
{
     uint8 byResult;
    for(;;)
    {
        byResult = GetFlashStatus();
        if(byResult & 0x80)
        {
          break;
        }
    }
  Delay(2);
}


unsigned long GetFlashStatus()
{
   uint8 ret;
   unsigned long ret1;
   GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, 0);  //chip select low
   SSIDataPut(SSI0_BASE, 0x57);
   SSIDataGet(SSI0_BASE, &ret1);
  GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, SSI_CS);//chip select high  
  ret=(uint8)ret1;
  return ret;
 

}

My code is not working and it is hang in Df_ReadyBusy() function ,help me please................

over 11 years ago

0 Dhanush Nair over 11 years ago

Expert 1360 points

please tell me whether any mistake in my code ...my SPI conf. is right or wrong .....is there need of dummy bit

0 Petrei over 11 years ago in reply to Dhanush Nair

Guru 26105 points

Hi,

Two problems with your code:

a) while first you enabled the SSI1 peripheral, all further SPI functions calls uses SSI0;

b) while erasing and writing the EEPROM: first send the command and then wait for completion (i.e. remove the calls to status at the beginning and let it active while command is executing).

And one more - did not checked the data sheet of your device, but some EEPROMs need to write to them Write_enable command first before the write command - check your device sheet to see if that is the case.

Petrei

0 Dhanush Nair over 11 years ago in reply to Petrei

Expert 1360 points

Hi Petrei ,

I have successfully completed reading and writing with GPIO ( so there is no problem of Write_enable ) , but i am unable to do the same with SPI

As suggested by you ,

Petrei said:

Two problems with your code:

a) while first you enabled the SSI1 peripheral, all further SPI functions calls uses SSI0;

b) while erasing and writing the EEPROM: first send the command and then wait for completion (i.e. remove the calls to status at the beginning and let it active while command is executing).

#define SSI_CLK       GPIO_PIN_0
#define SSI_CS        GPIO_PIN_1
#define SSI_TX        GPIO_PIN_3
#define SSI_RX        GPIO_PIN_2 

unsigned long data; 
int main(void){
  
    unsigned long BufReception;
  
    SysCtlClockSet(SYSCTL_SYSDIV_4 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN |
                   SYSCTL_XTAL_8MHZ);
    
    SysCtlPeripheralEnable(SYSCTL_PERIPH_SSI1);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE); 
    
    GPIOPinConfigure(GPIO_PE0_SSI1CLK); //==========configure clk
    GPIOPinConfigure(GPIO_PE2_SSI1RX);//  ==========configure Rx
    GPIOPinConfigure(GPIO_PE3_SSI1TX);//  ==========configure Tx

    GPIOPinTypeGPIOOutPut(GPIO_PORTA_BASE, SSI_CS);
    GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, SSI_CS);
    GPIOPinTypeSSI(GPIO_PORTA_BASE, SSI_CLK | SSI_TX | SSI_RX );

    SSIConfigSetExpClk(SSI0_BASE, SysCtlClockGet(), SSI_FRF_MOTO_MODE_0, 
                       SSI_MODE_MASTER, 1000000, 8);
    
    SSIEnable(SSI0_BASE);
 DelayUs(10); //10uSec
 Spi_erase();
 Buffer_write(); // buffer 1 write
 Buffer_read(); // buffer 1 read
 LcdDisplay(data);//lcd display
 
 }

void Spi_erase()
{ 
 uint16 block_counter = 0;
 unit8 addfld[2];

Df_ReadyBusy(); while(block_counter<512) //total 512 block { addfld[0]=((uint8)(block_counter>>4)); addfld[1]=((uint8)(block_counter<<4)); GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, 0); //chip select low SSIDataPut(SSI1_BASE, 0x50); //block erase SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI1_BASE, &addfld[0]); SSIDataGet(SSI1_BASE, &dummyBuf); SSIDataPut(SSI1_BASE, &addfld[0]); //24 bits address SSIDataGet(SSI1_BASE, &dummyBuf); SSIDataPut(SSI1_BASE, 0x00); SSIDataGet(SSI1_BASE, &dummyBuf);

GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, SSI_CS);//chip select high Df_ReadyBusy(); }

}

void buffer_read()
{ 

      GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, 0);  //chip select low
    SSIDataPut(SSI1_BASE, 0xD4);  //read buffer 1

Df_ReadyBusy();

SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI1_BASE, 0x00); SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI1_BASE, 0x00); //24 bits address SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI1_BASE, 0x00); SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer

SSIDataPut(SSI1_BASE, 0x00);

SSIDataGet(SSI1_BASE, &data);//read data in 'data'

GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, SSI_CS);//chip select high Df_ReadyBusy();

}

void buffer_write()
{ 
     
     GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, 0);  //chip select low
  SSIDataPut(SSI1_BASE, 0x84);  //read buffer 1

      Df_ReadyBusy();

SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer

SSIDataPut(SSI1_BASE, 0x00); SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI1_BASE, 0x00); //24 bits address SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI1_BASE, 0x00); SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer

SSIDataGet(SSI1_BASE, 0x41); // 'A' character

GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, SSI_CS);//chip select high Df_ReadyBusy();

}

void  Df_ReadyBusy()
{
     uint8 byResult;
    for(;;)
    {
        byResult = GetFlashStatus();
        if(byResult & 0x80)
        {
          break;
        }
    }
  Delay(2);
}


unsigned long GetFlashStatus()
{
   uint8 ret;
   unsigned long ret1;
   GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, 0);  //chip select low
   SSIDataPut(SSI1_BASE, 0x57);
   SSIDataGet(SSI1_BASE, &ret1);
  GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, SSI_CS);//chip select high  
  ret=(uint8)ret1;
  return ret;
 

}


I have done changes as you told and added these commands

 GPIOPinConfigure(GPIO_PE0_SSI1CLK); //==========configure clk
 GPIOPinConfigure(GPIO_PE2_SSI1RX);//  ==========configure Rx
 GPIOPinConfigure(GPIO_PE3_SSI1TX);//  ==========configure Tx
But still it is not working.Every time it read command read 255 only.I think there is problem in "SSI" configure but where i dont know

0 Petrei over 11 years ago in reply to Dhanush Nair

Guru 26105 points

Hi,

In this code (and similar) :

void buffer_write()
{ 
     
     GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, 0);  //chip select low
  SSIDataPut(SSI1_BASE, 0x84);  //read buffer 1

      Df_ReadyBusy();

Your call to this function Df.... first set CS low, then high, so further access to SPI is done with CS high, instead low, so that's why I suggested you to remove this function at this place.

Next, changing from SPI0 to needed SPI1 implies also some other pins - I did not cheched if they are the corect ones.

Petrei

0 Dhanush Nair over 11 years ago in reply to Petrei

Expert 1360 points

HI,

I HAVE DONE CHANGES BUT STILL IT IS NOT WORKING..

AS U SAID

Petrei said:
Hi,

In this code (and similar) :
void buffer_write()
{ 
     
     GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, 0);  //chip select low
  SSIDataPut(SSI1_BASE, 0x84);  //read buffer 1  
      Df_ReadyBusy();
Your call to this function Df.... first set CS low, then high, so further access to SPI is done with CS high, instead low, so that's why I suggested you to remove this function at this place.

Next, changing from SPI0 to needed SPI1 implies also some other pins - I did not cheched if they are the corect ones.

Petrei

STILL.....EVERY TIME IT READ 225

#define SSI_CLK       GPIO_PIN_0
#define SSI_CS        GPIO_PIN_1
#define SSI_TX        GPIO_PIN_3
#define SSI_RX        GPIO_PIN_2 

unsigned long data; 
int main(void){
  
    unsigned long BufReception;
  
    SysCtlClockSet(SYSCTL_SYSDIV_4 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN |
                   SYSCTL_XTAL_8MHZ);
    
    SysCtlPeripheralEnable(SYSCTL_PERIPH_SSI1);
    SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE); 
    
    GPIOPinConfigure(GPIO_PE0_SSI1CLK); //==========configure clk
    GPIOPinConfigure(GPIO_PE2_SSI1RX);//  ==========configure Rx
    GPIOPinConfigure(GPIO_PE3_SSI1TX);//  ==========configure Tx

    GPIOPinTypeGPIOOutPut(GPIO_PORTA_BASE, SSI_CS);
    GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, SSI_CS);
    GPIOPinTypeSSI(GPIO_PORTA_BASE, SSI_CLK | SSI_TX | SSI_RX );

    SSIConfigSetExpClk(SSI0_BASE, SysCtlClockGet(), SSI_FRF_MOTO_MODE_0, 
                       SSI_MODE_MASTER, 1000000, 8);
    
    SSIEnable(SSI0_BASE);
 DelayUs(10); //10uSec
 Spi_erase();
 Buffer_write(); // buffer 1 write
 Buffer_read(); // buffer 1 read
 LcdDisplay(data);//lcd display
 
 }

void Spi_erase()
{ 
 uint16 block_counter = 0;
 unit8 addfld[2];

Df_ReadyBusy(); while(block_counter<512) //total 512 block { addfld[0]=((uint8)(block_counter>>4)); addfld[1]=((uint8)(block_counter<<4)); GPIOPinWrite(GPIO_PORTA_BASE, SSI_CS, 0); //chip select low SSIDataPut(SSI1_BASE, 0x50); //block erase SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer SSIDataPut(SSI1_BASE, &addfld[0]); SSIDataGet(SSI1_BASE, &dummyBuf); SSIDataPut(SSI1_BASE, &addfld[0]); //24 bits address SSIDataGet(SSI1_BASE, &dummyBuf); SSIDataPut(SSI1_BASE, 0x00); SSIDataGet(SSI1_BASE, &dummyBuf);

GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, SSI_CS);//chip select high Df_ReadyBusy(); }

}

void buffer_read()
{ 

      GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, 0);  //chip select low
    SSIDataPut(SSI1_BASE, 0xD4);  //read buffer 1

SSIDataPut(SSI1_BASE,dummyBuf);

SSIDataGet(SSI1_BASE, &data);//read data in 'data'

GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, SSI_CS);//chip select high Df_ReadyBusy();

}

void buffer_write()
{ 
     
     GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, 0);  //chip select low
  SSIDataPut(SSI1_BASE, 0x84);  //read buffer 1

SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer

SSIDataPut(SSI1_BASE, 0x41); // 'A' character

SSIDataGet(SSI1_BASE, &dummyBuf);//dummy to clear write buffer

GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, SSI_CS);//chip select high Df_ReadyBusy();

}

void  Df_ReadyBusy()
{
     uint8 byResult;
    for(;;)
    {
        byResult = GetFlashStatus();
        if(byResult & 0x80)
        {
          break;
        }
    }
  Delay(2);
}


unsigned long GetFlashStatus()
{
   uint8 ret;
   unsigned long ret1;
   GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, 0);  //chip select low
   SSIDataPut(SSI1_BASE, 0x57);
   SSIDataGet(SSI1_BASE, &ret1);
  GPIOPinWrite(GPIO_PORTE_BASE, SSI_CS, SSI_CS);//chip select high  
  ret=(uint8)ret1;
  return ret;
 

}

0 Petrei over 11 years ago in reply to Dhanush Nair

Guru 26105 points

Hi,

How did you configured the SPI? To use mode0 - but for this mode you should toggle CS pin for every transmitted word (Check the user manual). Also take into account the right SPI sequence - first you send something (Put) and then you read (Get) - check to see if you matched this way all your writes/reads (seems you modified in the last version). Use an oscilloscope and debug using breakpoints. Check the SPI pins status.

Also, as a general programming methodology, try to apply the "top-down" approach rather than "bottom-up" as it seems you have done. The last one is prone to errors and time consuming.

0 Petrei over 11 years ago in reply to Petrei

Guru 26105 points

Hi,

I downloaded the data sheet of your device and reading it confirmed my supposition in a previous post - this device has both hardware and software write protection. For hardware point of view: if you did not used, at least must have a pull-up resistor on /WP pin, do not let it floating. For software point of view, it is wise to send first the disable sector protection command before any write (see paragraph 8.1.2).

Also, it is wise to use mode 3 - less hardware toggling. Try automatic toggling.

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AT45DB081D serial EEPROM code not working ( uC LM3s5951 is used)