//*****************************************************************************
static void
OSRAMWriteFirst(unsigned char ucChar)
{
    //
    // Set the slave address.
    //
    I2CMasterSlaveAddrSet(I2C_MASTER_BASE, SSD0303_ADDR, false);

    //
    // Write the first byte to the controller.
    //
    I2CMasterDataPut(I2C_MASTER_BASE, ucChar);

    //
    // Start the transfer.
    //
    I2CMasterControl(I2C_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_START);
}

//*****************************************************************************
//
//! \internal
//!
//! Write a byte to the SSD0303 controller.
//!
//! \param ucChar is the byte to be transmitted to the controller.
//!
//! This function continues a transfer to the SSD0303 controller by writing
//! another byte over the I2C bus.  This must only be called after calling
//! OSRAMWriteFirst(), but before calling OSRAMWriteFinal().
//!
//! The data is written in a polled faashion; this function will not return
//! until the byte has been written to the controller.
//!
//! \return None.
//
//*****************************************************************************
static void
OSRAMWriteByte(unsigned char ucChar)
{
    //
    // Wait until the current byte has been transferred.
    //
    while(I2CMasterIntStatus(I2C_MASTER_BASE, false) == 0)
    {
    }

    //
    // Provide the required inter-byte delay.
    //
    OSRAMDelay(g_ulDelay);

    //
    // Write the next byte to the controller.
    //
    I2CMasterDataPut(I2C_MASTER_BASE, ucChar);

    //
    // Continue the transfer.
    //
    I2CMasterControl(I2C_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_CONT);
}

//*****************************************************************************
//
//! \internal
//!
//! Write a sequence of bytes to the SSD0303 controller.
//!
//! This function continues a transfer to the SSD0303 controller by writing a
//! sequence of bytes over the I2C bus.  This must only be called after calling
//! OSRAMWriteFirst(), but before calling OSRAMWriteFinal().
//!
//! The data is written in a polled fashion; this function will not return
//! until the entire byte sequence has been written to the controller.
//!
//! \return None.
//
//*****************************************************************************
static void
OSRAMWriteArray(const unsigned char *pucBuffer, unsigned long ulCount)
{
    //
    // Loop while there are more bytes left to be transferred.
    //
    while(ulCount != 0)
    {
        //
        // Wait until the current byte has been transferred.
        //
        while(I2CMasterIntStatus(I2C_MASTER_BASE, false) == 0)
        {
        }

        //
        // Provide the required inter-byte delay.
        //
        OSRAMDelay(g_ulDelay);

        //
        // Write the next byte to the controller.
        //
        I2CMasterDataPut(I2C_MASTER_BASE, *pucBuffer++);
        ulCount--;

        //
        // Continue the transfer.
        //
        I2CMasterControl(I2C_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_CONT);
    }
}

//*****************************************************************************
//
//! \internal
//!
//! Finish a transfer to the SSD0303 controller.
//!
//! \param ucChar is the final byte to be written to the controller.
//!
//! This function will finish a transfer to the SSD0303 controller via the I2C
//! bus.  This must only be called after calling OSRAMWriteFirst().
//!
//! The data is written in a polled fashion; this function will not return
//! until the byte has been written to the controller.
//!
//! \return None.
//
//*****************************************************************************
static void
OSRAMWriteFinal(unsigned char ucChar)
{
    //
    // Wait until the current byte has been transferred.
    //
    while(I2CMasterIntStatus(I2C_MASTER_BASE, false) == 0)
    {
    }

    //
    // Provide the required inter-byte delay.
    //
    OSRAMDelay(g_ulDelay);

    //
    // Write the final byte to the controller.
    //
    I2CMasterDataPut(I2C_MASTER_BASE, ucChar);

    //
    // Finish the transfer.
    //
    I2CMasterControl(I2C_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_FINISH);

    //
    // Wait until the final byte has been transferred.
    //
    while(I2CMasterIntStatus(I2C_MASTER_BASE, false) == 0)
    {
    }

    //
    // Provide the required inter-byte delay.
    //
    OSRAMDelay(g_ulDelay);
}

//*****************************************************************************
//
//! Clears the OLED display.
//!
//! This function will clear the display.  All pixels in the display will be
//! turned off.
//!
//! This function is contained in <tt>osram96x16.c</tt>, with
//! <tt>osram96x16.h</tt> containing the API definition for use by
//! applications.
//!
//! \return None.
//
//*****************************************************************************
void
OSRAMClear(void)
{
    static const unsigned char pucRow1[] =
    {
        0xb0, 0x80, 0x04, 0x80, 0x12, 0x40
    };
    static const unsigned char pucRow2[] =
    {
        0xb1, 0x80, 0x04, 0x80, 0x12, 0x40
    };
    unsigned long ulIdx;

    //
    // Move the display cursor to the first column of the first row.
    //
    OSRAMWriteFirst(0x80);
    OSRAMWriteArray(pucRow1, sizeof(pucRow1));

    //
    // Fill this row with zeros.
    //
    for(ulIdx = 0; ulIdx < 95; ulIdx++)
    {
        OSRAMWriteByte(0x00);
    }
    OSRAMWriteFinal(0x00);

    //
    // Move the display cursor to the first column of the second row.
    //
    OSRAMWriteFirst(0x80);
    OSRAMWriteArray(pucRow2, sizeof(pucRow2));

    //
    // Fill this row with zeros.
    //
    for(ulIdx = 0; ulIdx < 95; ulIdx++)
    {
        OSRAMWriteByte(0x00);
    }
    OSRAMWriteFinal(0x00);
}

//*****************************************************************************
//
//! Displays a string on the OLED display.
//!
//! \param pcStr is a pointer to the string to display.
//! \param ulX is the horizontal position to display the string, specified in
//! columns from the left edge of the display.
//! \param ulY is the vertical position to display the string, specified in
//! eight scan line blocks from the top of the display (i.e. only 0 and 1 are
//! valid).
//!
//! This function will draw a string on the display.  Only the ASCII characters
//! between 32 (space) and 126 (tilde) are supported; other characters will
//! result in random data being draw on the display (based on whatever appears
//! before/after the font in memory).  The font is mono-spaced, so characters
//! such as "i" and "l" have more white space around them than characters such
//! as "m" or "w".
//!
//! If the drawing of the string reaches the right edge of the display, no more
//! characters will be drawn.  Therefore, special care is not required to avoid
//! supplying a string that is "too long" to display.
//!
//! This function is contained in <tt>osram96x16.c</tt>, with
//! <tt>osram96x16.h</tt> containing the API definition for use by
//! applications.
//!
//! \return None.
//
//*****************************************************************************
void
OSRAMStringDraw(const char *pcStr, unsigned long ulX, unsigned long ulY)
{
    //
    // Check the arguments.
    //
    ASSERT(ulX < 96);
    ASSERT(ulY < 2);

    //
    // Move the display cursor to the requested position on the display.
    //
    OSRAMWriteFirst(0x80);
    OSRAMWriteByte((ulY == 0) ? 0xb0 : 0xb1);
    OSRAMWriteByte(0x80);
    OSRAMWriteByte((ulX + 36) & 0x0f);
    OSRAMWriteByte(0x80);
    OSRAMWriteByte(0x10 | (((ulX + 36) >> 4) & 0x0f));
    OSRAMWriteByte(0x40);

    //
    // Loop while there are more characters in the string.
    //
    while(*pcStr != 0)
    {
        //
        // See if there is enough space on the display for this entire
        // character.
        //
        if(ulX <= 90)
        {
            //
            // Write the contents of this character to the display.
            //
            OSRAMWriteArray(g_pucFont[*pcStr - ' '], 5);

            //
            // See if this is the last character to display (either because the
            // right edge has been reached or because there are no more
            // characters).
            //
            if((ulX == 90) || (pcStr[1] == 0))
            {
                //
                // Write the final column of the display.
                //
                OSRAMWriteFinal(0x00);

                //
                // The string has been displayed.
                //
                return;
            }

            //
            // Write the inter-character padding column.
            //
            OSRAMWriteByte(0x00);
        }
        else
        {
            //
            // Write the portion of the character that will fit onto the
            // display.
            //
            OSRAMWriteArray(g_pucFont[*pcStr - ' '], 95 - ulX);
            OSRAMWriteFinal(g_pucFont[*pcStr - ' '][95 - ulX]);