File content as of revision 20:6e2e4a8372eb:

#ifndef RA8875_H
#define RA8875_H
#include <mbed.h>

#include "GraphicsDisplay.h"

#define RA8875_DEFAULT_SPI_FREQ 1000000

// Define this to enable code that monitors the performance of various
// graphics commands.
//#define PERF_METRICS

// What better place for some test code than in here...
#define TESTENABLE

#define RGB(r,g,b) ( ((r<<8)&0xF800) | ((g<<3)&0x07E0) | (b>>3) )

/// DOS colors - slightly color enhanced
#define Black       (color_t)(RGB(0,0,0))
#define Blue        (color_t)(RGB(0,0,187))
#define Green       (color_t)(RGB(0,187,0))
#define Cyan        (color_t)(RGB(0,187,187))
#define Red         (color_t)(RGB(187,0,0))
#define Magenta     (color_t)(RGB(187,0,187))
#define Brown       (color_t)(RGB(187,187,0))
#define Gray        (color_t)(RGB(187,187,187))
#define Charcoal    (color_t)(RGB(85,85,85))
#define BrightBlue  (color_t)(RGB(85,85,255))
#define BrightGreen (color_t)(RGB(85,255,85))
#define BrightCyan  (color_t)(RGB(85,255,255))
#define Orange      (color_t)(RGB(255,85,85))
#define Pink        (color_t)(RGB(255,85,255))
#define Yellow      (color_t)(RGB(255,255,85))
#define White       (color_t)(RGB(255,255,255))

#define BrightRed   (color_t)(RGB(255,0,0))

//namespace SW_graphics
//{

/// color type definition to let the compiler help keep us honest.
/// 
/// colors can be defined with the RGB(r,g,b) macro, and there
/// are a number of predefined colors:
/// - Black,    Blue,       Green,       Cyan,
/// - Red,      Magenta,    Brown,       Gray,
/// - Charcoal, BrightBlue, BrightGreen, BrightCyan,
/// - Orange,   Pink,       Yellow,      White
///
typedef uint16_t color_t;   

/// background fill info for drawing Text, Rectangles, RoundedRectanges, Circles, Ellipses and Triangles.
typedef enum
{
    NOFILL,     ///< do not fill the object with the background color
    FILL        ///< fill the object space with the background color
} fill_t;

/// return values from functions
//typedef enum
//{
//    noerror,
//    bad_parameter
//} RetCode_t;

class RA8875 : public GraphicsDisplay
{
public:   
    /// font type selection.
    typedef enum
    {
        ISO8859_1,
        ISO8859_2,
        ISO8859_3,
        ISO8859_4
    } font_t;
    
    /// font rotation selection
    typedef enum
    {
        normal,
        rotated
    } font_angle_t;
    
    /// alignment  
    typedef enum
    {
        align_none,
        align_full
    } alignment_t;    
    
    /// Scale factor - 1, 2, 3 4
    typedef unsigned int HorizontalScale;
    
    /// Scale factor - 1, 2, 3, 4
    typedef unsigned int VerticalScale;

    /// Clear screen region
    typedef enum
    {
        FULLWINDOW,
        ACTIVEWINDOW
    } Region_t;
    
    /// Constructor for a display based on the RAiO RA8875 
    /// display controller.
    ///
    /// @param mosi is the SPI master out slave in pin on the mbed.
    /// @param miso is the SPI master in slave out pin on the mbed.
    /// @param sclk is the SPI shift clock pin on the mbed.
    /// @param csel is the DigitalOut pin on the mbed to use as the
    ///         active low chip select for the display controller.
    /// @param reset is the DigitalOut pin on the mbed to use as the 
    ///         active low reset input on the display controller - 
    ///         but this is not currently used.
    /// @param name is a text name for this object, which will permit
    ///         capturing stdout and printf() directly to it.
    ///
    RA8875(PinName mosi, PinName miso, PinName sclk, PinName csel, PinName reset, const char * name = "lcd");
    
    /// Destructor doesn't have much to do.
    //~RA8875();
    
    /// Write a command to the display
    ///
    /// This is a high level command, and may invoke several primitives.
    ///
    /// @param command is the command to write.
    /// @data is optional data to be written to the command register
    ///     and only occurs if the data is in the range [0 - 0xFF].
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t WriteCommand(unsigned char command, unsigned int data = 0xFFFF);
    
    /// Write a data byte to the display
    ///
    /// This is a high level command, and may invoke several primitives.
    ///
    /// @param data is the data to write.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t WriteData(unsigned char data);
    
    /// Read a command register
    ///
    /// @param command is the command register to read.
    /// @returns the value read from the register.
    ///
    unsigned char ReadCommand(unsigned char command);
    
    /// Read a data byte to the display
    ///
    /// This is a high level command, and may invoke several primitives.
    ///
    /// @returns data that was read.
    ///
    unsigned char ReadData(void);
    
    /// Read the display status
    ///
    /// This is a high level command, and may invoke several primitives.
    ///
    /// @returns data that was read.
    ///
    unsigned char ReadStatus(void);

    /// get the width in pixels of the currently active font
    ///
    /// @returns font width in pixels.
    ///    
    unsigned int fontwidth(void);
    
    /// get the height in pixels of the currently active font
    ///
    /// @returns font height in pixels.
    ///    
    unsigned int fontheight(void);
    
    /// get the number of colums based on the currently active font
    ///
    /// @returns number of columns.
    ///    
    virtual int columns(void);

    /// get the number of rows based on the currently active font
    ///
    /// @returns number of rows.
    ///    
    virtual int rows(void);

    /// get the screen width in pixels
    ///
    /// @returns screen width in pixels.
    ///
    virtual int width(void);

    /// get the screen height in pixels
    ///
    /// @returns screen height in pixels.
    ///
    virtual int height(void);

    /// Set cursor position based on the current font size.
    /// 
    /// @param x is the horizontal position in character positions
    /// @param y is the vertical position in character positions
    /// @returns success/failure code. @see RetCode_t.
    ///
    virtual RetCode_t locate(unsigned int x, unsigned int y);

    /// Prepare the controller to write text to the screen by positioning
    /// the cursor.
    ///
    /// @param x is the horizontal position in pixels (from the left edge)
    /// @param y is the vertical position in pixels (from the top edge)
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t SetTextCursor(unsigned int x, unsigned int y);
    
    /// Select the ISO 8859-X font to use next.
    ///
    /// Supported fonts: ISO 8859-1, -2, -3, -4
    ///
    /// @param font selects the font for the subsequent text rendering.
    ///
    /// @note if either hScale or vScale is outside of its permitted range,
    ///     the command is not executed.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t SetTextFont(font_t font = ISO8859_1);
    
    /// Control the font behavior.
    ///
    /// This command lets you make several modifications to any text that
    /// is written.
    ///
    /// Options can be combined:
    /// Default:
    /// @li Full alignment disabled, 
    /// @li Font with Background color, 
    /// @li Font in normal orientiation,
    /// @li Horizontal scale x 1
    /// @li Vertical scale x 1
    /// @li alignment
    /// 
    /// @param fillit defaults to FILL, but can be NOFILL
    /// @param angle defaults to normal, but can be rotated
    /// @param hScale defaults to 1, but can be 1, 2, 3, or 4,
    ///     and scales the font size by this amount.
    /// @param vScale defaults to 1, but can be 1, 2, 3, or 4,
    ///     and scales the font size by this amount.
    /// @param alignment defaults to align_none, but can be
    ///     align_full.
    /// 
    /// @note if either hScale or vScale is outside of its permitted range,
    ///     the command is not executed.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t SetTextFontControl(fill_t fillit = FILL, 
        font_angle_t angle = normal, 
        HorizontalScale hScale = 1, 
        VerticalScale vScale = 1, 
        alignment_t alignment = align_none);
    
    /// Control the font size
    ///
    /// This command lets you set the font enlargement for both horizontal
    /// and vertical, independent of the rotation, background, and 
    /// alignment. @see SetTextFontControl.
    ///
    /// @param hScale defaults to 1, but can be 1, 2, 3, or 4,
    ///     and scales the font size by this amount.
    /// @param vScale defaults to 1, but can be 1, 2, 3, or 4,
    ///     and scales the font size by this amount.
    ///
    /// @note if either hScale or vScale is outside of its permitted range,
    ///     the command is not executed.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t SetTextFontSize(HorizontalScale hScale = 1, VerticalScale vScale = 1);
    
    /// put a character on the screen.
    ///
    /// @param c is the character.
    /// @returns the character, or EOF if there is an error.
    ///
    virtual int _putc(int c);

    /// Write string of text to the display
    ///
    /// @param string is the null terminated string to send to the display.
    ///
    void puts(const char * string);
    
    /// Write string of text to the display at the specified location.
    ///
    /// @param x is the horizontal position in pixels (from the left edge)
    /// @param y is the vertical position in pixels (from the top edge)
    /// @param string is the null terminated string to send to the display.
    ///
    void puts(unsigned int x, unsigned int y, const char * string);
    
    /// Prepare the controller to write binary data to the screen by positioning
    /// the memory cursor.
    ///
    /// @param x is the horizontal position in pixels (from the left edge)
    /// @param y is the vertical position in pixels (from the top edge)
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t SetMemoryCursor(unsigned int x, unsigned int y);
    
    /// Set the window, which controls where items are written to the screen.
    ///
    /// When something hits the window width, it wraps back to the left side
    /// and down a row. If the initial write is outside the window, it will
    /// be captured into the window when it crosses a boundary.
    ///
    /// @param x is the left edge in pixels.
    /// @param y is the top edge in pixels.
    /// @param width is the window width in pixels.
    /// @param height is the window height in pixels.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t SetWindow(unsigned int x, unsigned int y, unsigned int width, unsigned int height);
    
    /// Clear the screen.
    ///
    /// The behavior is to clear the whole screen. @see clsw().
    ///
    /// @returns success/failure code. @see RetCode_t.
    ///
    virtual RetCode_t cls(void);
    
    /// Clear the screen, or clear only the active window.
    ///
    /// The default behavior is to clear the whole screen. With the optional 
    /// parameter, the action can be restricted to the active window, which
    /// can be set with the @see SetWindow method.
    ///
    /// @param region is an optional parameter that defaults to FULLWINDOW
    ///         or may be set to ACTIVEWINDOW.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t clsw(RA8875::Region_t region = FULLWINDOW);

    /// Set the background color.
    ///
    /// @param color is expressed in 16-bit format.
    /// @returns success/failure code. @see RetCode_t.
    ///
    virtual RetCode_t background(color_t color);
    
    /// Set the background color.
    ///
    /// @param r is the red element of the color.
    /// @param g is the green element of the color.
    /// @param b is the blue element of the color.
    /// @returns success/failure code. @see RetCode_t.
    ///
    virtual RetCode_t background(unsigned char r, unsigned char g, unsigned char b);
    
    /// Set the foreground color.
    ///
    /// @param color is expressed in 16-bit format.
    /// @returns success/failure code. @see RetCode_t.
    ///
    virtual RetCode_t foreground(color_t color);
    
    /// Set the foreground color.
    ///
    /// @param R is the red element of the color.
    /// @param G is the green element of the color.
    /// @param B is the blue element of the color.
    /// @returns success/failure code. @see RetCode_t.
    ///
    virtual RetCode_t foreground(unsigned char R, unsigned char G, unsigned char B);
    
    /// Get the current foreground color value.
    ///
    /// @returns the current foreground color.
    ///
    unsigned int GetForeColor(void);
        
    /// Draw a pixel in the specified color.
    ///
    /// @note As a side effect, this also sets the foreground color 
    ///     affecting all subsequent operations.
    ///
    /// @param x is the horizontal offset to this pixel.
    /// @param y is the vertical offset to this pixel.
    /// @param color defines the color for the pixel.
    /// @returns success/failure code. @see RetCode_t.
    ///
    virtual RetCode_t pixel(unsigned int x, unsigned int y, color_t color);
    
    /// Draw a pixel in the current foreground color.
    ///
    /// @param x is the horizontal offset to this pixel.
    /// @param y is the veritical offset to this pixel.
    /// @returns success/failure code. @see RetCode_t.
    ///
    virtual RetCode_t pixel(unsigned int x, unsigned int y);
    
    /// Draw a line in the specified color
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x1 is the horizontal start of the line.
    /// @param y1 is the vertical start of the line.
    /// @param x2 is the horizontal end of the line.
    /// @param y2 is the vertical end of the line.
    /// @param color defines the foreground color.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t line(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        color_t color);

    /// Draw a line
    ///
    /// Draws a line using the foreground color setting.
    ///
    /// @param x1 is the horizontal start of the line.
    /// @param y1 is the vertical start of the line.
    /// @param x2 is the horizontal end of the line.
    /// @param y2 is the vertical end of the line.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t line(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2);

    /// Draw a rectangle in the specified color
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x1 is the horizontal start of the line.
    /// @param y1 is the vertical start of the line.
    /// @param x2 is the horizontal end of the line.
    /// @param y2 is the vertical end of the line.
    /// @param color defines the foreground color.
    /// @param fillit is optional to FILL the rectangle. default is NOFILL.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t rect(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        color_t color, fill_t fillit = NOFILL);

    /// Draw a filled rectangle in the specified color
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x1 is the horizontal start of the line.
    /// @param y1 is the vertical start of the line.
    /// @param x2 is the horizontal end of the line.
    /// @param y2 is the vertical end of the line.
    /// @param color defines the foreground color.
    /// @param fillit is optional to NOFILL the rectangle. default is FILL.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t fillrect(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        color_t color, fill_t fillit = FILL);

    /// Draw a rectangle
    ///
    /// Draws a rectangle using the foreground color setting.
    ///
    /// @param x1 is the horizontal start of the line.
    /// @param y1 is the vertical start of the line.
    /// @param x2 is the horizontal end of the line.
    /// @param y2 is the vertical end of the line.
    /// @param fillit is optional to FILL the rectangle. default is NOFILL.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t rect(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        fill_t fillit = NOFILL);

    /// Draw a filled rectangle with rounded corners using the specified color.
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x1 is the horizontal start of the line.
    /// @param y1 is the vertical start of the line.
    /// @param x2 is the horizontal end of the line.
    /// @param y2 is the vertical end of the line.
    /// @param radius1 defines the horizontal width of the curved corner.
    /// @param radius2 defines the vertical width of the curved corner.
    /// @param color defines the foreground color.
    /// @param fillit is optional to FILL the rectangle. default is NOFILL.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t fillroundrect(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        unsigned int radius1, unsigned int radius2, color_t color, fill_t fillit = FILL);

    /// Draw a rectangle with rounded corners using the specified color.
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x1 is the horizontal start of the line.
    /// @param y1 is the vertical start of the line.
    /// @param x2 is the horizontal end of the line.
    /// @param y2 is the vertical end of the line.
    /// @param radius1 defines the horizontal width of the curved corner.
    /// @param radius2 defines the vertical width of the curved corner.
    /// @param color defines the foreground color.
    /// @param fillit is optional to FILL the rectangle. default is NOFILL.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t roundrect(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        unsigned int radius1, unsigned int radius2, color_t color, fill_t fillit = NOFILL);

    /// Draw a rectangle with rounded corners.
    ///
    /// Draws a rectangle with rounded corners using the foreground color setting.
    ///
    /// @param x1 is the horizontal start of the line.
    /// @param y1 is the vertical start of the line.
    /// @param x2 is the horizontal end of the line.
    /// @param y2 is the vertical end of the line.
    /// @param radius1 defines the horizontal width of the curved corner.
    /// @param radius2 defines the vertical width of the curved corner.
    /// @param fillit is optional to FILL the rectangle. default is NOFILL.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t roundrect(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        unsigned int radius1, unsigned int radius2, fill_t fillit = NOFILL);

    /// Draw a triangle in the specified color.
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x1 is the horizontal for point 1.
    /// @param y1 is the vertical for point 1.
    /// @param x2 is the horizontal for point 2.
    /// @param y2 is the vertical for point 2.
    /// @param x3 is the horizontal for point 3.
    /// @param y3 is the vertical for point 3.
    /// @param color defines the foreground color.
    /// @param fillit is optional to FILL the rectangle. default is NOFILL.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t triangle(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        unsigned int x3, unsigned int y3, color_t color, fill_t fillit = NOFILL);
    
    /// Draw a filled triangle in the specified color.
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x1 is the horizontal for point 1.
    /// @param y1 is the vertical for point 1.
    /// @param x2 is the horizontal for point 2.
    /// @param y2 is the vertical for point 2.
    /// @param x3 is the horizontal for point 3.
    /// @param y3 is the vertical for point 3.
    /// @param color defines the foreground color.
    /// @param fillit is optional to FILL the rectangle. default is NOFILL.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t filltriangle(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        unsigned int x3, unsigned int y3, color_t color, fill_t fillit = FILL);

    /// Draw a triangle
    ///
    /// Draws a triangle using the foreground color setting.
    ///
    /// @param x1 is the horizontal for point 1.
    /// @param y1 is the vertical for point 1.
    /// @param x2 is the horizontal for point 2.
    /// @param y2 is the vertical for point 2.
    /// @param x3 is the horizontal for point 3.
    /// @param y3 is the vertical for point 3.
    /// @param fillit is optional to FILL the rectangle. default is NOFILL.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t triangle(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, 
        unsigned int x3, unsigned int y3, fill_t fillit = NOFILL);
    
    /// Draw a circle using the specified color.
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x is the horizontal center of the circle.
    /// @param y is the vertical center of the circle.
    /// @param radius defines the size of the circle.
    /// @param color defines the foreground color.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t circle(unsigned int x, unsigned int y, unsigned int radius, color_t color, fill_t fillit = NOFILL);

    /// Draw a filled circle using the specified color.
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x is the horizontal center of the circle.
    /// @param y is the vertical center of the circle.
    /// @param radius defines the size of the circle.
    /// @param color defines the foreground color.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t fillcircle(unsigned int x, unsigned int y, unsigned int radius, color_t color, fill_t fillit = FILL);

    /// Draw a circle.
    ///
    /// Draws a circle using the foreground color setting.
    ///
    /// @param x is the horizontal center of the circle.
    /// @param y is the vertical center of the circle.
    /// @param radius defines the size of the circle.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t circle(unsigned int x, unsigned int y, unsigned int radius, fill_t fillit = NOFILL);

    /// Draw an Ellipse using the specified color
    ///
    /// @note As a side effect, this changes the current
    ///     foreground color for subsequent operations.
    ///
    /// @param x is the horizontal center of the ellipse.
    /// @param y is the vertical center of the ellipse.
    /// @param radius1 defines the horizontal width of the ellipse.
    /// @param radius2 defines the vertical width of the ellipse.
    /// @param color defines the foreground color.
    /// @param fillit defines whether the circle is filled or not.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t ellipse(unsigned int x, unsigned int y, unsigned int radius1, unsigned int radius1, 
        color_t color, fill_t fillit = NOFILL);

    /// Draw an Ellipse
    ///
    /// Draws it using the foreground color setting.
    ///
    /// @param x is the horizontal center of the ellipse.
    /// @param y is the vertical center of the ellipse.
    /// @param radius1 defines the horizontal width of the ellipse.
    /// @param radius2 defines the vertical width of the ellipse.
    /// @param fillit defines whether the circle is filled or not.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t ellipse(unsigned int x, unsigned int y, unsigned int radius1, unsigned int radius1, fill_t fillit = NOFILL);
    
    /// Control display power
    ///
    /// @param on when set to true will turn on the display, when false it is turned off.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t Power(bool on);

    /// Reset the display controller via the Software Reset interface.
    ///
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t Reset(void);
    
    /// Set backlight brightness.
    ///
    /// When the built-in PWM is used to control the backlight, this 
    /// API can be used to set the brightness.
    /// 
    /// @param brightness ranges from 0 (off) to 255 (full on)
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t Backlight_u8(unsigned char brightness);
    
    /// Set backlight brightness.
    ///
    /// When the built-in PWM is used to control the backlight, this 
    /// API can be used to set the brightness.
    /// 
    /// @param brightness ranges from 0.0 (off) to 1.0 (full on)
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t Backlight(float brightness);

    /// Set a reference to a bitmap font, provided by the user.
    ///
    /// @note Tool to create the fonts is accessible from its creator
    ///     available at http://www.mikroe.com. 
    ///     Change the data to an array of type char[].
    ///
    /// @param font is a pointer to a specially formed font array.
    ///     This special font array has a 4-byte header, followed by 
    ///     the data:
    ///   - the number of bytes per char
    ///   - the vertical size in pixels for each character
    ///   - the horizontal size in pixels for each character
    ///   - the number of bytes per vertical line (width of the array)
    /// @returns error code.
    ///
    RetCode_t set_font(const unsigned char * font);

    /// Get the RGB value for a DOS color.
    ///
    /// @param i is the color, in the range 0 to 15;
    /// @returns the RGB color of the selected index, or 0 
    ///     if the index is out of bounds.
    ///
    color_t DOSColor(int i);

    /// Get the color name (string) for a DOS color.
    ///
    /// @param i is the color, in the range 0 to 15;
    /// @returns a pointer to a string with the color name,
    ///     or NULL if the index is out of bounds.
    /// 
    const char * DOSColorNames(int i);


#ifdef PERF_METRICS
    /// Clear the performance metrics to zero.
    void ClearPerformance();
    
    /// Report the performance metrics for drawing functions using
    /// printf()
    void ReportPerformance();
#endif

private:
    /// Set the SPI port frequency (in Hz).
    ///
    /// @note attempts to call this API at runtime, with the display
    ///         already online, cause the system to lockup. 
    ///         Not sure why, so moving this to private to run once.
    ///
    /// This uses the mbed SPI driver, and is therefore dependent on
    /// its capabilities. Limited tests were performed for the display
    /// in the range of 1,000,000 to 50,000,000 Hz. The display was
    /// a bit erratic above 20,000,000 Hz, so this became the default,
    /// even though it might have been the bench-level wiring that posed
    /// the limit.
    ///
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t frequency(unsigned long Hz = RA8875_DEFAULT_SPI_FREQ);
    

    /// Initialize the chip, which is normally done as part of the
    /// constructor, so not called by the user.
    ///
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t init(void);
    
    /// Select the peripheral to use it.
    ///
    /// @param chipsel when true will select the peripheral, and when false
    ///     will deselect the chip. This is the logical selection, and
    ///     the pin selection is the invert of this.
    /// @returns success/failure code. @see RetCode_t.
    ///
    RetCode_t select(bool chipsel);

    /// The most primitive - to write a data value to the SPI interface.
    ///
    /// @param data is the value to write.
    /// @returns a value read from the port, since SPI is often shift
    ///     in while shifting out.
    ///
    unsigned char spiwrite(unsigned char data);
    
    /// The most primitive - to read a data value to the SPI interface.
    ///
    /// This is really just a specialcase of the write command, where
    /// the value zero is written in order to read.
    ///
    /// @returns a value read from the port, since SPI is often shift
    ///     in while shifting out.
    ///
    unsigned char spiread();
    
    SPI spi;                        ///< spi port
    DigitalOut cs;                  ///< chip select pin, assumed active low
    DigitalOut res;                 ///< reset pin, assumed active low
    const unsigned char * font;     ///< reference to an external font somewhere in memory
    
    #ifdef PERF_METRICS
    typedef enum
    {
        PRF_CLS,
        PRF_DRAWPOINT,
        PRF_DRAWLINE,
        PRF_DRAWRECTANGLE,
        PRF_DRAWROUNDEDRECTANGLE,
        PRF_DRAWTRIANGLE,
        PRF_DRAWCIRCLE,
        PRF_DRAWELLIPSE,
        METRICCOUNT
    } method_e;
    unsigned long metrics[METRICCOUNT];
    void RegisterPerformance(method_e method);
    Timer performance;
    #endif
};

//}     // namespace

//using namespace SW_graphics;

#endif