Display library

Data Structures
struct	display_t

Macros
#define	DISPLAY_HEIGHT   240
#define	DISPLAY_WIDTH   240

Enumerations
enum	colors {   RGB_RED = 0xf800 , RGB_GREEN = 0x07e0 , RGB_BLUE = 0x001f , RGB_BLACK = 0x0000 ,   RGB_WHITE = 0xffff , RGB_GRAY = 0x8c51 , RGB_YELLOW = 0xFFE0 , RGB_CYAN = 0x07FF ,   RGB_PURPLE = 0xF81F }
enum	directions {   TEXT_DIRECTION0 = 0 , TEXT_DIRECTION90 = 1 , TEXT_DIRECTION180 = 2 , TEXT_DIRECTION270 = 3 ,   NUM_TEXT_DIRECTIONS }

Functions
void	display_init (display_t *display)
void	display_destroy (display_t *display)
void	displayDrawPixel (display_t *display, uint16_t x, uint16_t y, uint16_t color)
void	displayDrawFillRect (display_t *display, uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2, uint16_t color)
void	displayFillScreen (display_t *display, uint16_t color)
void	displayDrawLine (display_t *display, uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2, uint16_t color)
void	displayDrawRect (display_t *display, uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2, uint16_t color)
void	displayDrawRectAngle (display_t *display, uint16_t xc, uint16_t yc, uint16_t w, uint16_t h, uint16_t angle, uint16_t color)
void	displayDrawTriangleCenter (display_t *display, uint16_t xc, uint16_t yc, uint16_t w, uint16_t h, uint16_t angle, uint16_t color)
void	displayDrawCircle (display_t *display, uint16_t x_center, uint16_t y_center, uint16_t r, uint16_t color)
void	displayDrawFillCircle (display_t *display, uint16_t x_center, uint16_t y_center, uint16_t r, uint16_t color)
void	displayDrawRoundRect (display_t *display, uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2, uint16_t r, uint16_t color)
uint16_t	rgb_conv (uint16_t r, uint16_t g, uint16_t b)
int	displayDrawChar (display_t *display, FontxFile *fx, uint16_t x, uint16_t y, uint8_t ascii, uint16_t color)
int	displayDrawString (display_t *display, FontxFile *fx, uint16_t x, uint16_t y, uint8_t *ascii, uint16_t color)
void	displaySetFontDirection (display_t *display, uint16_t dir)
void	displaySetFontFill (display_t *display, uint16_t color)
void	displayUnsetFontFill (display_t *display)
void	displaySetFontUnderLine (display_t *display, uint16_t color)
void	displayUnsetFontUnderLine (display_t *display)
void	displayDisplayOff (display_t *display)
void	displayDisplayOn (display_t *display)
void	displayBacklightOff (display_t *display)
void	displayBacklightOn (display_t *display)
void	displayInversionOff (display_t *display)
void	displayInversionOn (display_t *display)
void	displayDrawTriangle (display_t *display, uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2, uint16_t x3, uint16_t y3, uint16_t color)
void	display_set_flip (display_t *display, bool xflip, bool yflip)

Detailed Description

Wrappers to simplify the use of the TFT LCD display.

Define a display_t display (called the display "handle"), initialise it, and pass this as the first parameter to all functions.

Warning

All functions fail with program exit if any pixel of the shape that is drawn is outside the display dimensions.

An example of how to use this library.

#include <libpynq.h>
int main (void)
{
  // initialise all I/O
  pynq_init();
  display_t display;
  display_init(&display);
 
  displayFillScreen(&display, RGB_RED);
  // drawing is simple
  displayDrawPixel(&display, 50, 50, RGB_YELLOW);
  displayDrawFillRect(&display, 10, 100, 110, 200, RGB_RED);
  displayDrawCircle(&display, 60, 40, 15, RGB_RED);
  // text is more involved
  FontxFile fx16G[2];
  // the font file must be reachable from the directory
  // from which the executable is run -- see InitFontx
  InitFontx(fx16G, "../../fonts/ILGH16XB.FNT", "");
  GetFontx(fx16G, 0, buffer_fx16G, &fontWidth_fx16G, &fontHeight_fx16G);
  displaySetFontDirection(&display, TEXT_DIRECTION0);
  uint8_t text[] = "hello";
  displayDrawString(&display, fx16G, 15, fontHeight_fx16G * 6, text1,
RGB_WHITE);
 
  // clean up after use
  display_destroy(&display);
  pynq_destroy();
  return EXIT_SUCCESS;
}

Macro Definition Documentation

DISPLAY_HEIGHT

#define DISPLAY_HEIGHT   240

Definition at line 83 of file display.h.

DISPLAY_WIDTH

#define DISPLAY_WIDTH   240

Definition at line 84 of file display.h.

Enumeration Type Documentation

colors

enum colors

Colors that can be used with the display.

Enumerator
RGB_RED
RGB_GREEN
RGB_BLUE
RGB_BLACK
RGB_WHITE
RGB_GRAY
RGB_YELLOW
RGB_CYAN
RGB_PURPLE

Definition at line 89 of file display.h.

directions

enum directions

Enum of directions the text can be printed on on the display.

Enumerator
TEXT_DIRECTION0
TEXT_DIRECTION90
TEXT_DIRECTION180
TEXT_DIRECTION270
NUM_TEXT_DIRECTIONS

Definition at line 104 of file display.h.

Function Documentation

display_destroy()

void display_destroy ( display_t *  display )

extern

Stop using the display.

Parameters

display

Handle to display.

display_init()

void display_init ( display_t *  display )

extern

Initialize the display display.

Parameters

display

Handle to display.

Definition at line 301 of file display.c.

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display_set_flip()

void display_set_flip	(	display_t *	display,
		bool	xflip,
		bool	yflip
	)

Flip the drawing off the screen.

Parameters

display	Handle to display
xflip	Flip in the X direction
yflip	Flip in the Y direction

Definition at line 279 of file display.c.

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displayBacklightOff()

void displayBacklightOff ( display_t *  display )

extern

Turn off the display backlight.

Parameters

display

Handle to display.

Definition at line 1014 of file display.c.

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displayBacklightOn()

void displayBacklightOn ( display_t *  display )

extern

Turn on the display backlight.

Parameters

display

Handle to display.

Definition at line 1023 of file display.c.

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displayDisplayOff()

void displayDisplayOff ( display_t *  display )

extern

Turn off the display.

Parameters

display

Handle to display.

Definition at line 403 of file display.c.

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displayDisplayOn()

void displayDisplayOn ( display_t *  display )

extern

Initialize DISPLAY screen.

Parameters

display	Handle to display.
width	Width of screen in pixels.
height	Height of screen in pixels.
offsetx	Horizontal offset.
offsety	Vertical offset.

Definition at line 410 of file display.c.

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displayDrawChar()

int displayDrawChar ( display_t *  display, FontxFile *  fx, uint16_t  x, uint16_t  y, uint8_t  ascii, uint16_t  color  )

extern

Draws a character on the given coordinates of the display.

Parameters

display	Handle to display.
fx	Pointer to font-file that is used for drawing the text.
x	The x-coordinate of the text on the display.
y	The y-coordinate of the text on the display.
ascii	The ascii character to draw.
color	The 16-bit color value to write.

Returns

The x-value of the next character to be printed on the display.

Warning

The font-file path must be valid from the directory in which the executable is called, otherwise the error message "cannot get font from font file" will be thrown. Absolute paths (starting with /) are safe. See documentation for InitFontx.

Definition at line 782 of file display.c.

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displayDrawCircle()

void displayDrawCircle ( display_t *  display, uint16_t  x_center, uint16_t  y_center, uint16_t  r, uint16_t  color  )

extern

Draw a circle without infill on the display.

Parameters

display	Handle to display.
x_center	X-coordinate of the center of the circle.
y_center	Y-coordinate of the center of the circle.
r	The radius of the circle in pixels.
color	The 16-bit color value to write.

Definition at line 621 of file display.c.

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displayDrawFillCircle()

void displayDrawFillCircle ( display_t *  display, uint16_t  x_center, uint16_t  y_center, uint16_t  r, uint16_t  color  )

extern

Draw a circle with infill on the display.

Parameters

display	Handle to display.
x_center	X-coordinate of the center of the circle.
y_center	Y-coordinate of the center of the circle.
r	The radius of the circle in pixels.
color	The 16-bit color value to write.

Definition at line 662 of file display.c.

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displayDrawFillRect()

void displayDrawFillRect ( display_t *  display, uint16_t  x1, uint16_t  y1, uint16_t  x2, uint16_t  y2, uint16_t  color  )

extern

Draw a filled rectangle to the display.

Parameters

display	Handle to display.
x1	The X coordinate of the top-left corner of the rectangle.
y1	The Y coordinate of the top-left corner of the rectangle.
x2	The X coordinate of the bottom-right corner of the rectangle.
y2	The Y coordinate of the bottom-right corner of the rectangle.
color	The 16-bit color value to write.

Definition at line 361 of file display.c.

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displayDrawLine()

void displayDrawLine ( display_t *  display, uint16_t  x1, uint16_t  y1, uint16_t  x2, uint16_t  y2, uint16_t  color  )

extern

Draw a line from two coordinates.

Parameters

display	Handle to display.
x1	Starting x-coordinate of line.
y1	Starting y-coordinate of line.
x2	Ending x-coordinate of line.
y2	Ending y-coordinate of line.
color	The 16-bit color value to write.

Definition at line 425 of file display.c.

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displayDrawPixel()

void displayDrawPixel ( display_t *  display, uint16_t  x, uint16_t  y, uint16_t  color  )

extern

Draw a single pixel to the display.

Parameters

display	Handle to display.
x	The X coordinate of the pixel.
y	The Y coordinate of the pixel.
color	The 16-bit color value to write.

Definition at line 317 of file display.c.

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displayDrawRect()

void displayDrawRect ( display_t *  display, uint16_t  x1, uint16_t  y1, uint16_t  x2, uint16_t  y2, uint16_t  color  )

extern

Draw a filled rectangle.

Parameters

display	Handle to display.
x1	Top-left x-coordinate of rectangle.
y1	Top-left y-coordinate of rectangle.
x2	Bottom-right x-coordinate of rectangle.
y2	Bottom-right y-coordinate of rectangle.
color	The 16-bit color value to write.

Definition at line 478 of file display.c.

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displayDrawRectAngle()

void displayDrawRectAngle ( display_t *  display, uint16_t  xc, uint16_t  yc, uint16_t  w, uint16_t  h, uint16_t  angle, uint16_t  color  )

extern

Draws a rectangle with rounded corners at a specified angle on the display.

Parameters

display	Handle to display.
xc	X-coordinate of the center of the rectangle.
yc	Y-coordinate of the center of the rectangle.
w	Width of the rectangle.
h	Height of the rectangle.
angle	Angle of rotation in degrees.
color	The 16-bit color value to write.

Definition at line 496 of file display.c.

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displayDrawRoundRect()

void displayDrawRoundRect ( display_t *  display, uint16_t  x1, uint16_t  y1, uint16_t  x2, uint16_t  y2, uint16_t  r, uint16_t  color  )

extern

Draw a rectangle with rounded angles.

Parameters

display	Handle to display.
x1	Top-left x-coordinate of rectangle.
y1	Top-left y-coordinate of rectangle.
x2	Bottom-right x-coordinate of rectangle.
y2	Bottom-right y-coordinate of rectangle.
r	The radius of the circle that is used for the edges.
color	The 16-bit color value to write.

Definition at line 708 of file display.c.

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displayDrawString()

int displayDrawString ( display_t *  display, FontxFile *  fx, uint16_t  x, uint16_t  y, uint8_t *  ascii, uint16_t  color  )

extern

Function to draw a string on the display.

Parameters

display	Handle to display.
fx	Pointer to font-file that is used for drawing the text.
x	The x-coordinate of the text on the display.
y	The y-coordinate of the text on the display.
ascii	The ascii characters to draw.
color	The 16-bit color value to write.

Returns

The x or y coordinate of the next character, depending on the orientation of the display.

Warning

The font-file path must be valid from the directory in which the executable is called, otherwise the error message "cannot get font from font file" will be thrown. Absolute paths (starting with /) are safe. See documentation for InitFontx.

Definition at line 951 of file display.c.

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displayDrawTriangle()

void displayDrawTriangle ( display_t *  display, uint16_t  x1, uint16_t  y1, uint16_t  x2, uint16_t  y2, uint16_t  x3, uint16_t  y3, uint16_t  color  )

extern

Draw a triangle without infill between the three given points in the given color.

Parameters

display	Handle to display.
x1	The first X-coordinate of the triangle.
y1	The first Y-coordinate of the triangle.
x2	The second X-coordinate of the triangle.
y2	The second Y-coordinate of the triangle.
x3	The third X-coordinate of the triangle.
y3	The third Y-coordinate of the triangle.
color	The 16-bit color value to write.

Definition at line 553 of file display.c.

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displayDrawTriangleCenter()

void displayDrawTriangleCenter ( display_t *  display, uint16_t  xc, uint16_t  yc, uint16_t  w, uint16_t  h, uint16_t  angle, uint16_t  color  )

extern

Draws a triangle at a specified angle on the display.

Parameters

display	Handle to display.
xc	X-coordinate of the center of the rectangle.
yc	Y-coordinate of the center of the rectangle.
w	Width of the rectangle.
h	Height of the rectangle.
angle	Angle of rotation in degrees.
color	The 16-bit color value to write.

Definition at line 580 of file display.c.

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displayFillScreen()

void displayFillScreen ( display_t *  display, uint16_t  color  )

extern

Fill entire display with a single color using the ldcDrawFillRect function.

Parameters

display	Handle to display.
color	Fill color in RGB format.

Definition at line 417 of file display.c.

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displayInversionOff()

void displayInversionOff ( display_t *  display )

extern

Turn off inversion of the colors.

Parameters

display

Handle to display.

Definition at line 1032 of file display.c.

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displayInversionOn()

void displayInversionOn ( display_t *  display )

extern

Turn on inversion of the colors.

Parameters

display

Handle to display.

Definition at line 1039 of file display.c.

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displaySetFontDirection()

void displaySetFontDirection ( display_t *  display, uint16_t  dir  )

extern

Changes the direction the characters will be printed.

Parameters

display	Handle to display.
dir	The direction to set the font in the display handle.

Definition at line 982 of file display.c.

displaySetFontFill()

void displaySetFontFill ( display_t *  display, uint16_t  color  )

extern

Enables the _font_fill and sets the _font_fill_color in the display handle.

Parameters

display	Handle to display.
color	The fill-color the font should have

Definition at line 989 of file display.c.

displaySetFontUnderLine()

void displaySetFontUnderLine ( display_t *  display, uint16_t  color  )

extern

Turns on _font_underline in the display handle and sets the _font_underline_color to the specified color.

Parameters

display	Handle to display.
color	The 16-bit color value to write.

Definition at line 999 of file display.c.

displayUnsetFontFill()

void displayUnsetFontFill ( display_t *  display )

extern

Sets the _font_fill parameter to false in the display handle, turns off the font fill.

Parameters

display

Handle to display.

Definition at line 997 of file display.c.

displayUnsetFontUnderLine()

void displayUnsetFontUnderLine ( display_t *  display )

extern

Turns off _font_underline in the display handle.

Parameters

display

Handle to display.

Definition at line 1007 of file display.c.

rgb_conv()

uint16_t rgb_conv ( uint16_t  r, uint16_t  g, uint16_t  b  )

extern

RGB conversion for generating a color.

Parameters

r	Red value, 5 least significant bits.
g	Green value, 6 least significant bits.
b	Blue value, 5 least significant bits.

Definition at line 778 of file display.c.