1.1.5.2.2 Using the Library

The SST39 driver provides the blocking APIs to read, write and erase SST39 memory.

The SST39 driver can be used in following ways:

To perform sector erase operation
To perform chip erase operation
To perform page write to the SST39
To read the product identification codes of the SST39

Example Application to Erase, Write and Read SST39 Memory

#define BUFFER_SIZE                       (DRV_SST39_PAGE_SIZE)
#define SST39_MANUFACTURER_ID             (0xBFU)
#define SST39_DEVICE_ID                   (0xD7U)

APP_DATA appData;

void APP_Initialize ( void )
{
    uint32_t i = 0;

    /* Place the App state machine in its initial state. */
    appData.state = APP_STATE_INIT;

    for (i = 0; i < BUFFER_SIZE; i++)
    {
        appData.writeBuffer[i] = i;
    }
}

void APP_Tasks ( void )
{

    /* Check the application's current state. */
    switch ( appData.state )
    {
        /* Application's initial state. */
        case APP_STATE_INIT:
        {
            if (DRV_SST39_Status(DRV_SST39_INDEX) == SYS_STATUS_READY)
            {
                appData.state = APP_STATE_OPEN_DRIVER;
            }
            break;
        }

        case APP_STATE_OPEN_DRIVER:
        {
            appData.handle = DRV_SST39_Open((SYS_MODULE_INDEX)DRV_SST39_INDEX, DRV_IO_INTENT_READWRITE);

            if (appData.handle != DRV_HANDLE_INVALID)
            {
                appData.state = APP_STATE_ID_GET;
            }
            break;
        }

        case APP_STATE_ID_GET:
        {
            if (DRV_SST39_ReadProductId(appData.handle, &appData.readManId, &appData.readDeviceId) != true)
            {
                appData.state = APP_STATE_ERROR;
            }
            else
            {
                if ( (appData.readManId == SST39_MANUFACTURER_ID) && (appData.readDeviceId == SST39_DEVICE_ID) )
                {
                    appData.state = APP_STATE_ERASE_FLASH;
                }
            }
            break;
        }

        case APP_STATE_ERASE_FLASH:
        {
            if (DRV_SST39_ChipErase(appData.handle) != true)
            {
                appData.state = APP_STATE_ERROR;
            }
            else
            {
                appData.state = APP_STATE_WRITE_MEMORY;
            }
            break;
        }

        case APP_STATE_WRITE_MEMORY:
        {
            if (DRV_SST39_PageWrite(appData.handle, appData.writeBuffer, 0x60000000U) != true)
            {
                appData.state = APP_STATE_ERROR;
            }
            else
            {
                appData.state = APP_STATE_READ_MEMORY;
            }
            break;
        }
        
        case APP_STATE_READ_MEMORY:
        {
            if (DRV_SST39_Read(appData.handle, appData.readBuffer, BUFFER_SIZE, 0x60000000U) != true)
            {
                appData.state = APP_STATE_ERROR;
            }
            else
            {
                appData.state = APP_STATE_VERIFY_DATA;
            }
            break;
        }    

        case APP_STATE_VERIFY_DATA:
        {
            if (!memcmp(appData.writeBuffer, appData.readBuffer, BUFFER_SIZE))
            {
                appData.state = APP_STATE_SUCCESS;
            }
            else
            {
                appData.state = APP_STATE_ERROR;
            }
            break;
        }

        case APP_STATE_SUCCESS:
        case APP_STATE_ERROR:
        default:
            break;
    }
}