u8glib_usermanual

1 . My favorites ▼ | Sign in u8glib Universal Graphics Library for 8 Bit Embedded Systems Search projects Project Home Wiki Issues Source Search Current pages for Search userreference User Reference Manual Featured Updated Jun 28, 2014 by olikr...@gmail.com User Reference Manual begin disableCursor drawBitmap drawBitmapP drawBox drawCircle drawDisc drawEllipse drawFilledEllipse drawFrame drawHLine drawLine drawPixel drawRBox drawRFrame drawStr drawStr90 drawStr180 drawStr270 drawStrP drawStr90P drawStr180P drawStr270P drawTriangle drawVLine drawXBM drawXBMP enableCursor firstPage getColorIndex getFontAscent getFontDescent getFontLineSpacing getHeight getMode getWidth getStrWidth InitSPI , InitHWSPI , Init8Bit InitComFn nextPage print setColorIndex setContrast setCursorColor setCursorFont setCursorPos setCursorStyle setDefaultBackgroundColor setDefaultForegroundColor setDefaultMidColor setFont 

2 . setFontLineSpacingFactor setFontPosBaseline setFontPosBottom setFontPosCenter setFontPosTop setFontRefHeightAll setFontRefHeightExtendedText setFontRefHeightText setHardwareBackup setPrintPos setRGB setRot90 setRot180 setRot270 setScale2x2 sleepOn sleepOff undoRotation undoScale U8GLIB User Reference Manual begin C++ Prototype uint8_t U8GLIB::begin(void) C Prototype uint8_t u8g_Begin(u8g_t *u8g) Description Reset display and put it into default state. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: 0, if the init procedure fails. Use: Outside picture loop. Note: Available with v1.11. Example: See also: U8GLIB disableCursor C++ Prototype void U8GLIB::disableCursor(void) C Prototype void u8g_DisableCursor(u8g_t *u8g) Description Disable the cursor. The cursor will not be visible. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: Use: 

3 . Outside picture loop. Note: Example: See also: enableCursor, setCursorColor, setCursorFont, setCursorPos, setCursorStyle drawBitmap drawBitmapP C++ Prototype void U8GLIB::drawBitmap(u8g_uint_t x, u8g_uint_t y, u8g_uint_t cnt, u8g_uint_t h, const uint8_t *bitmap) void U8GLIB::drawBitmapP(u8g_uint_t x, u8g_uint_t y, u8g_uint_t cnt, u8g_uint_t h, const u8g_pgm_uint8_t *bitmap) C Prototype void u8g_DrawBitmap(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t cnt, u8g_uint_t h, const uint8_t *bitmap) void u8g_DrawBitmapP(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t cnt, u8g_uint_t h, const u8g_pgm_uint8_t *bitmap) Description Draw a bitmap at the specified x/y position (upper left corner of the bitmap). Parts of the bitmap may be outside the display boundaries. The bitmap is specified by the array bitmap. A cleared bit means: Do not draw a pixel. A set bit inside the array means: Write pixel with the current color index. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position (left position of the bitmap). y: Y-position (upper position of the bitmap). cnt: Number of bytes of the bitmap in horizontal direction. The width of the bitmap is cnt*8. h: Height of the bitmap. Returns: Use: Inside picture loop. Note: Example: U8GLIB_PCD8544 u8g(13, 11, 10, 9, 8); // SPI communication: SCK = 13, MOSI = 11, CS = 10, A0 = 9, Reset = 8 const uint8_t rook_bitmap[] U8G_PROGMEM = { 0x00, // 00000000 0x55, // 01010101 0x7f, // 01111111 0x3e, // 00111110 0x3e, // 00111110 0x3e, // 00111110 0x3e, // 00111110 0x7f // 01111111 }; void draw(void) { // graphic commands to redraw the complete screen should be placed here u8g.drawBitmapP( 0, 0, 1, 8, rook_bitmap); } void setup(void) { } void loop(void) { // picture loop u8g.firstPage(); do { draw(); } while( u8g.nextPage() ); // rebuild the picture after some delay delay(1000); } 

4 . See also: setColorIndex drawXBM drawBox C++ Prototype void U8GLIB::drawBox(u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h) C Prototype void u8g_DrawBox(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h) Description Draw a box (filled frame), starting at x/y position (upper left edge). The box has width w and height h. Parts of the box can be outside of the display boundaries. This procedure uses the current color index to draw the box. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position of upper left edge. y: Y-position of upper left edge. w: Width of the box. h: Height of the box. Returns: Use: Inside picture loop. Note: Example: U8GLIB u8g(...) ... u8g.drawBox(10,12,20,30); See also: setColorIndex, drawFrame drawCircle C++ Prototype void U8GLIB::drawCircle(u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rad, uint8_t opt = U8G_DRAW_ALL) C Prototype void u8g_DrawCircle(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rad, uint8_t opt) Description Draw a circle with radus rad at position (x0, y0). The diameter of the circle is 2*rad+1 Depending on opt, it is possible to draw only some sections of the circle. Possible values for opt are: U8G_DRAW_UPPER_RIGHT, U8G_DRAW_UPPER_LEFT, U8G_DRAW_LOWER_LEFT, U8G_DRAW_LOWER_RIGHT, U8G_DRAW_ALL. These values can be combined with the | operator. Arguments: u8g : Pointer to the u8g structure (C interface only). x0, y0: Position of the center of the circle. rad: Defines the size of the circle: Radus = rad. opt: Selects some or all sections of the circle. 

5 . U8G_DRAW_UPPER_RIGHT U8G_DRAW_UPPER_LEFT U8G_DRAW_LOWER_LEFT U8G_DRAW_LOWER_RIGHT U8G_DRAW_ALL Returns: Use: Inside picture loop. Note: Available with v1.02 Example: u8g.drawCircle(20, 20, 14); u8g.drawCircle(20, 20, 14, U8G_DRAW_UPPER_RIGHT); See also: drawDisc drawDisc C++ Prototype void U8GLIB::drawDisc(u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rad, uint8_t opt = U8G_DRAW_ALL) C Prototype void u8g_DrawDisc(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rad, uint8_t opt) Description Draw a filled circle with radus rad at position (x0, y0). The diameter of the circle is 2*rad+1 Depending on opt, it is possible to draw only some sections of the disc. Possible values for opt are: U8G_DRAW_UPPER_RIGHT, U8G_DRAW_UPPER_LEFT, U8G_DRAW_LOWER_LEFT, U8G_DRAW_LOWER_RIGHT, U8G_DRAW_ALL. These values can be combined with the | operator. Arguments: u8g : Pointer to the u8g structure (C interface only). x0, y0: Position of the center of the filled circle. rad: Defines the size of the disc: Radus = rad. opt: Selects some or all sections of the circle. U8G_DRAW_UPPER_RIGHT U8G_DRAW_UPPER_LEFT U8G_DRAW_LOWER_LEFT U8G_DRAW_LOWER_RIGHT U8G_DRAW_ALL Returns: Use: Inside picture loop. Note: Available with v1.02 

6 . Example: See drawCircle See also: drawCircle drawEllipse C++ Prototype void U8GLIB::drawEllipse(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rx, u8g_uint_t ry, uint8_t opt) C Prototype void u8g_DrawEllipse(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rx, u8g_uint_t ry, uint8_t opt) Description Draw ellipse with radus rx and 'ry' at position (x0, y0). rx*ry must be lower than 1024 in 8 Bit mode of u8glib. Depending on opt, it is possible to draw only some sections of the disc. Possible values for opt are: U8G_DRAW_UPPER_RIGHT, U8G_DRAW_UPPER_LEFT, U8G_DRAW_LOWER_LEFT, U8G_DRAW_LOWER_RIGHT, U8G_DRAW_ALL. These values can be combined with the | operator. Arguments: u8g : Pointer to the u8g structure (C interface only). x0, y0: Position of the center of the filled circle. rx, rx: Defines the size of the ellipse. opt: Selects some or all sections of the ellipse. U8G_DRAW_UPPER_RIGHT U8G_DRAW_UPPER_LEFT U8G_DRAW_LOWER_LEFT U8G_DRAW_LOWER_RIGHT U8G_DRAW_ALL Returns: Use: Inside picture loop. Note: Available with v1.14 See also: drawCircle drawFilledEllipse C++ Prototype void U8GLIB::drawFilledEllipse(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rx, u8g_uint_t ry, uint8_t opt) C Prototype void u8g_DrawFilledEllipse(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rx, u8g_uint_t ry, uint8_t opt) Description Draw a filled ellipse with radus rx and 'ry' at position (x0, y0). rx*ry must be lower than 1024 in 8 Bit mode of u8glib. Depending on opt, it is possible to draw only some sections of the disc. Possible values for opt are: U8G_DRAW_UPPER_RIGHT, U8G_DRAW_UPPER_LEFT, U8G_DRAW_LOWER_LEFT, U8G_DRAW_LOWER_RIGHT, U8G_DRAW_ALL. These values can be combined with the | operator. Arguments: u8g : Pointer to the u8g structure (C interface only). x0, y0: Position of the center of the filled circle. rx, rx: Defines the size of the ellipse. opt: Selects some or all sections of the ellipse. U8G_DRAW_UPPER_RIGHT U8G_DRAW_UPPER_LEFT U8G_DRAW_LOWER_LEFT U8G_DRAW_LOWER_RIGHT U8G_DRAW_ALL Returns: Use: Inside picture loop. 

7 . Note: Available with v1.14 See also: drawCircle drawFrame C++ Prototype void U8GLIB::drawFrame(u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h) C Prototype void u8g_DrawFrame(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h) Description Draw a frame, starting at x/y position (upper left edge). The frame has width w and height h. Parts of the frame can be outside of the display boundaries. This procedure uses the current color index to draw the lines of the frame. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position of upper left edge. y: Y-position of upper left edge. w: Width of the frame. h: Height of the frame. Returns: Use: Inside picture loop. Note: Example: U8GLIB u8g(...) ... u8g.drawFrame(10,12,30,20); See also: setColorIndex, drawBox drawHLine C++ Prototype void U8GLIB::drawHLine(u8g_uint_t x, u8g_uint_t y, u8g_uint_t w) C Prototype void u8g_DrawHLine(u8g_t *u8g, uint8_t x, uint8_t y, u8g_uint_t w) Description Draw a horizontal line, starting at x/y position (left edge). The width of the line is w pixels. Parts of the line can be outside of the display boundaries. This procedure uses the current color index to draw the line. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position. y: Y-position. w: Width of the horizontal line. Returns: 

8 . Use: Inside picture loop. Note: Example: See also: setColorIndex, drawVLine drawLine C++ Prototype void U8GLIB::drawLine(u8g_uint_t x1, u8g_uint_t y1, u8g_uint_t x2, u8g_uint_t y2) C Prototype void u8g_DrawLine(u8g_t *u8g, u8g_uint_t x1, u8g_uint_t y1, u8g_uint_t x2, u8g_uint_t y2) Description Draw a line from (x1, y1) to (x2, y2). There are no restrictions on the start end end position. This procedure uses the current color index to draw the line. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. Arguments: u8g : Pointer to the u8g structure (C interface only). x1, y1: Start position. x2, y2: End position. Returns: Use: Inside picture loop. Note: Available in v1.03. Example: u8g.drawLine(7, 10, 40, 55); See also: setColorIndex, drawVLine drawHLine drawPixel C++ Prototype void U8GLIB::drawPixel(uint8_t x, uint8_t y) C Prototype void u8g_DrawPixel(u8g_t *u8g, uint8_t x, uint8_t y) Description Draw a pixel at the specified x/y position. Position (0,0) is at the upper left corner of the display. The position may be outside the display boundaries. This procedure uses the current color index to draw the pixel. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position. y: Y-position. Returns: Use: 

9 . Inside picture loop. Note: Example: U8GLIB u8g(...) ... u8g.drawPixel(14,23); See also: setColorIndex drawRBox drawRFrame C++ Prototype void U8GLIB::drawRBox(u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h, u8g_uint_t r) void U8GLIB::drawRFrame(u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h, u8g_uint_t r) C Prototype void u8g_DrawRBox(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h, u8g_uint_t r) void u8g_DrawRFrame(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h, u8g_uint_t r) Description Draw a box/frame with round edges, starting at x/y position (upper left edge). The box/frame has width w and height h. Parts of the box can be outside of the display boundaries. Edges have radius r. It is required that w >= 2*(r+1) and h >= 2*(r+1). This condition is not checked. Behavior is undefined if w or h is smaller than 2*(r+1). This procedure uses the current color index to draw the box. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position of upper left edge. y: Y-position of upper left edge. w: Width of the box. h: Height of the box. r: Radius for the four edges. Returns: Use: Inside picture loop. Note: Available with v1.09 Note: See also: setColorIndex, drawFrame drawBox drawStr drawStr90 drawStr180 drawStr270 drawStrP drawStr90P drawStr180P 

10 .drawStr270P C++ Prototype u8g_uint_t U8GLIB::drawStr(u8g_uint_t x, u8g_uint_t y, const char *s) u8g_uint_t U8GLIB::drawStr90(u8g_uint_t x, u8g_uint_t y, const char *s) u8g_uint_t U8GLIB::drawStr180(u8g_uint_t x, u8g_uint_t y, const char *s) u8g_uint_t U8GLIB::drawStr270(u8g_uint_t x, u8g_uint_t y, const char *s) u8g_uint_t U8GLIB::drawStrP(u8g_uint_t x, u8g_uint_t y, const u8g_pgm_uint8_t *s) u8g_uint_t U8GLIB::drawStr90P(u8g_uint_t x, u8g_uint_t y, const u8g_pgm_uint8_t *s) u8g_uint_t U8GLIB::drawStr180P(u8g_uint_t x, u8g_uint_t y, const u8g_pgm_uint8_t *s) u8g_uint_t U8GLIB::drawStr270P(u8g_uint_t x, u8g_uint_t y, const u8g_pgm_uint8_t *s) C Prototype u8g_uint_t u8g_DrawStr(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, const char *s); u8g_uint_t u8g_DrawStr90(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, const char *s); u8g_uint_t u8g_DrawStr180(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, const char *s); u8g_uint_t u8g_DrawStr270(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, const char *s); u8g_uint_t u8g_DrawStrP(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, const u8g_pgm_uint8_t *s); u8g_uint_t u8g_DrawStr90P(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, const u8g_pgm_uint8_t *s); u8g_uint_t u8g_DrawStr180P(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, const u8g_pgm_uint8_t *s); u8g_uint_t u8g_DrawStr270P(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, const u8g_pgm_uint8_t *s); Description Draws a string at the specified x/y position. The x/y position is the lower left corner of the first character of the string. It is required to assign a font with the setFont procedure before the first call to this procedure. This procedure also uses the current color index to draw the characters. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. The (x,y) arguments are influenced by the reference point calculation mode (setFontPosBaseline). 'P' variant: s is assumed to point to a string in PROGMEM area. '90', '180', '270' variants: Rotate string output by 90, 180 or 270 degree. Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position. y: Y-position. s: A pointer to a C-string (terminated with \0). Returns: The width of the string s in pixel. Use: Inside picture loop. Note: The C++ Arduino environment also offers the more powerful print procedure. Example: U8GLIB u8g(...) ... u8g.setFont(u8g_font_osb18); u8g.drawStr(0, 20, "ABC"); The reference point (0,20) for the origin of the text string usually is one pixel below the lower left edge of the first character. The height of the uppercase letters is shown in the font overview bitmap (in this example 18, see here). In some cases the size of the uppercase letters is also part of the font name. See also: setColorIndex, setFont setFontPosBaseline print 

11 .drawTriangle C++ Prototype void U8GLIB::drawTriangle(uint16_t x0, uint16_t y0, uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2) C Prototype void u8g_DrawTriangle(u8g_t *u8g, uint16_t x0, uint16_t y0, uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2) Description Draw a triangle (filled polygon). Arguments are 16 bit and the polygon is clipped to the size of the display. Multiple polygons are drawn so that they exactly match without overlap: The left side of a polygon is drawn, the right side is not draw. The upper side is only draw if it is flat. In the example picture below, the pixel at (9,43) is drawn by the polygon procedures, but pixels (14,9) and (45,32) are not drawn. Arguments: u8g : Pointer to the u8g structure (C interface only). x0: X-position point 0. y0: Y-position point 0. x1: X-position point 1. y1: Y-position point 1. x2: X-position point 2. y2: Y-position point 2. Returns: Use: Inside picture loop. Note: Available with v1.15 Example: U8GLIB u8g(...) ... u8g.drawTriangle(14,9, 45,32, 9,42); u8g.drawTriangle(14,55, 45,33, 9,43); See also: setColorIndex drawVLine C++ Prototype void U8GLIB::drawVLine(u8g_uint_t x, u8g_uint_t y, u8g_uint_t h) C Prototype void u8g_DrawVLine(u8g_t *u8g, uint8_t x, uint8_t y, u8g_uint_t h) Description Draw a vertical line, starting at x/y position (upper edge). The height of the line is h pixels. Parts of the line can be outside of the display boundaries. This procedure uses the current color index to draw the line. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position. y: Y-position. h: Height of the horizontal line. Returns: 

12 . Use: Inside picture loop. Note: Example: See also: setColorIndex, drawHLine drawXBM drawXBMP C++ Prototype void U8GLIB::drawXBM(u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h, const uint8_t *bitmap) void U8GLIB::drawXBMP(u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h, const u8g_pgm_uint8_t *bitmap) C Prototype void u8g_DrawXBM(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h, const uint8_t *bitmap) void u8g_DrawXBMP(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t w, u8g_uint_t h, const u8g_pgm_uint8_t *bitmap) Description Draw a XBM Bitmap. Position (x,y) is the upper left corner of the bitmap. XBM contains monochrome, 1-bit bitmaps. This procedure only draws pixel values 1. The current color index is used for drawing (see setColorIndex). Pixel with value 0 are not drawn (transparent). Many tools can save a bitmap as XBM. The result will look like this example: #define u8g_logo_width 38 #define u8g_logo_height 24 static unsigned char u8g_logo_bits[] = { 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xe0, 0xe0, ... 0xff, 0x3f, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xff, 0xff, 0x3f }; This could can be copied directly into your code. Use drawXBM to draw this bitmap at (0,0): u8g.drawXBM( 0, 0, u8g_logo_width, u8g_logo_height, u8g_logo_bits); In most cases it is better to place the bitmap into AVR PROGMEM area. Add the U8G_PROGMEM after the array definition before the init sequence: static unsigned char u8g_logo_bits[] U8G_PROGMEM = { With this modification call the drawXBMP variant: u8g.drawXBMP( 0, 0, u8g_logo_width, u8g_logo_height, u8g_logo_bits); Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position. y: Y-position. w: Width of the bitmap. h: Height of the bitmap. bitmap: Pointer to the start of the bitmap. Returns: Use: Inside picture loop. Note: Example: 

13 . See also: setColorIndex, drawBitmap enableCursor C++ Prototype void U8GLIB::enableCursor(void) C Prototype void u8g_EnableCursor(u8g_t *u8g) Description Enable the cursor at the specified position. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: Use: Outside picture loop. Note: Example: See also: disableCursor, setCursorColor, setCursorFont, setCursorPos, setCursorStyle firstPage C++ Prototype void U8GLIB::firstPage(void) C Prototype void u8g_FirstPage(u8g_t *u8g) Description A call to this procedure, marks the beginning of the picture loop. Arguments: Returns: Use: This procedure call starts the picture loop; it cannot be used inside the picture loop. Picture loops cannot be nested. Note: Example: See also: nextPage getColorIndex C++ Prototype uint8_t U8GLIB::getColorIndex(void) C Prototype uint8_t u8g_GetColorIndex(u8g_t *u8g) Description The current "color index" is used by all "draw" procedures to set a pixel value on the display. This procedure returns the current value, which has been set as current color index. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: 

14 . Value, which is used by the "draw" procedures as a pixel value. Use: Inside and outside picture loop. Note: Example: See also: drawPixel setColorIndex getFontAscent C++ Prototype u8g_int_t U8GLIB::getFontAscent(void) C Prototype u8g_int_t u8g_GetFontAscentu8g_t *u8g) Description Returns the reference height of the glyphs above the baseline (ascent). This value depends on the current reference height (see setFontRefHeightAll). Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: The ascent of the current font. Use: Inside and outside picture loop. Note: Example: For u8g_font_10x20 the ascent is 13. u8g_SetFont(u8g, u8g_font_10x20); u8g_DrawStr(u8g, 5, 20, "ABCdefg"); a = u8g_GetFontAscent(u8g); The dotted line shows the baseline of the string. The string itself is above the baseline. The reference point for the string (5, 20) is exactly on the baseline. The ascent is the number of pixels of the highest glyph above baseline. To calculate the y position which is above the largest glyph, use baseline_y_pos-u8g_GetFontAscent(u8g)-1. See also: setFont getFontDescent setFontRefHeightAll getFontDescent C++ Prototype u8g_int_t U8GLIB::getFontDescent(void) C Prototype u8g_int_t u8g_GetFontDescent(u8g_t *u8g) Description Returns the reference height of the glyphs below the baseline (descent). Arguments: 

15 . u8g : Pointer to the u8g structure (C interface only). Returns: The descent of the current font. Use: Inside and outside picture loop. Note: Example: For u8g_font_10x20 the descent is -4. u8g_SetFont(u8g, u8g_font_10x20); u8g_DrawStr(u8g, 5, 20, "ABCdefg"); d = u8g_GetFontDescent(u8g); The dotted line shows the baseline of the string. The string itself is above the baseline. The reference point for the string (5, 20) is exactly on the baseline. The ascent is the number of pixels of the highest glyph above baseline. To calculate the y position which is below the glyph with the highest descent, use baseline_y_pos-u8g_GetFontDescent(u8g). See also: setFont getFontAscent getFontLineSpacing C++ Prototype u8g_int_t U8GLIB::getFontLineSpacing(void) C Prototype u8g_int_t u8g_getFontLineSpacing(u8g_t *u8g) Description Returns the vertical distance of two lines of text, written with the current font. This value is derived from the ascent and descent value and multiplied with the current LineSpacingFactor. The returned value is influenced by the current font, the "Reference Height" and the LineSpacingFactor. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: The distance of two lines (pixel). Use: Inside and outside picture loop. Note: See also: setFont getFontAscent getFontDescent setFontRefHeightAll setLineSpacingFactor getHeight C++ Prototype u8g_uint_t U8GLIB::getHeight(void) C Prototype u8g_uint_t u8g_GetHeight(u8g_t *u8g) Description 

16 . Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: The height of the display. Use: Inside and outside picture loop. Note: Example: See also: getWidth getMode C++ Prototype uint8_t U8GLIB::getMode(void) C Prototype uint8_t u8g_GetMode(u8g_t *u8g) Description Returns information about the display (display mode). The result of this procedure can be used to extract the number of bits per pixel: U8G_MODE_GET_BITS_PER_PIXEL(mode) Predefined modes are: U8G_MODE_BW: black/white monochrome mode with 1 bit per pixel U8G_MODE_GRAY2BIT: Graylevel mode with 2 bit per pixel Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: The current display mode. Use: Inside and outside picture loop. Note: Example: See also: getWidth C++ Prototype u8g_uint_t U8GLIB::getWidth(void) C Prototype u8g_uint_t u8g_GetWidth(u8g_t *u8g) Description Returns the width of the display. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: The width of the display. Use: 

17 . Inside and outside picture loop. Note: Example: This procedure will return 128 for an attached display with the dimensions 128x64. See also: getHeight getStrWidth C++ Prototype u8g_uint_t U8GLIB::getStrWidth(const char *s) u8g_uint_t U8GLIB::getStrWidthP(const u8g_pgm_uint8_t *s) C Prototype u8g_uint_t u8g_GetStrWidth(u8g_t *u8g, const char *s) u8g_uint_t u8g_GetStrWidthP(u8g_t *u8g, const u8g_pgm_uint8_t *s) Description Returns the width of the string "s", based on the current font. Arguments: u8g : Pointer to the u8g structure (C interface only). s : Pointer to a string. Returns: The width of the string. Use: Inside the picture loop. Note: Example: See Tutorial Font and String Handling See also: setFont InitSPI, InitHWSPI, Init8Bit InitComFn C Prototype uint8_t u8g_InitSPI(u8g_t *u8g, u8g_dev_t *dev, uint8_t sck, uint8_t mosi, uint8_t cs, uint8_t a0, uint8_t reset); uint8_t u8g_InitHWSPI(u8g_t *u8g, u8g_dev_t *dev, uint8_t cs, uint8_t a0, uint8_t reset); uint8_t u8g_Init8Bit(u8g_t *u8g, u8g_dev_t *dev, uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3, uint8_t d4, uint8_t d5, uint8_t d6 uint8_t en, uint8_t cs1, uint8_t cs2, uint8_t di, uint8_t rw, uint8_t reset); uint8_t u8g_InitComFn(u8g_t *u8g, u8g_dev_t *dev, u8g_com_fnptr com_fn); Description For the C-Interface only: Create a new interface to a graphics display. This procedure must be called before calling any other C- procedure. The dev argument describes the type of the display. See here for a complete list of available devices. u8g_InitComFn will be the default init precedure for the ARM plattfrom. It requires a specific low level procedure for the ARM controller. An examples for this procedure is here for the LPC1114 (end of u8g_arm.c). A more detailed description of the communication procedure can be found here: INSTALL Arguments: dev: A pointer to a device structure. Arduino pins: Required pins to connect the display depending on the communication interface. reset: The reset pin is optional and can be U8G_PIN_NONE com_fn: A procedure that handles low level access to the display. 

18 . Use: Outside picture loop. Note: u8g_InitComFn is avialble with v1.14. Example: See also: List of supported devices, U8GLIB C++ Constructor nextPage C++ Prototype uint8_t U8GLIB::nextPage(void) C Prototype uint8_t u8g_NextPage(u8g_t *u8g) Description A call to this procedure, marks the end of the body of the picture loop. Arguments: Returns: 0, if the picture loop has been finished, 1 if another redraw of the picture is required. Use: This procedure call marks the body of the picture loop, it can not be used inside the picture loop (Picture loops can not be nested). Note: This procedure will not reset or modify any internal values (like the draw color or the current font). The font settings and draw properties at the end of the body of the picture loop are still the same when the body of the picture loop is started again. Usually it is a good idea to set such properties at the beginning of the body of the picture loop. Example: See also: firstPage Picture Loop print C++ Prototype U8GLIB::print(...) C Prototype Description A call to the print procedure of the Print base class. See the documentation on the Arduino web page: http://arduino.cc/en/Serial/Print. print() behaves similar to drawStr. All font settings also apply to this procedure. All strings and values passed to the print procedure are written to the "print position". The "print position" can be set via setPrintPos. Arguments: See http://arduino.cc/en/Serial/Print Returns: See http://arduino.cc/en/Serial/Print Use: Inside the picture loop. Note: Example: See also: setPrintPos drawStr setColorIndex C++ Prototype void U8GLIB::setColorIndex(uint8_t color_index) 

19 . C Prototype void u8g_SetColorIndex(u8g_t *u8g, uint8_t color_index) Description The current "color index" is used by all "draw" procedures to set a pixel value on the display. For a monochrome display, the color index 0 will usually clear a pixel and the color index 1 will set a pixel. For a display which supports gray levels, this procedure sets the gray level for drawing. Arguments: u8g : Pointer to the u8g structure (C interface only). color_index: Value, which is used by the "draw" procedures as a pixel value. Returns: Use: Inside and outside picture loop. It is a good practice to use this procedure at the beginning of the body of the picture loop. Note: Example: U8GLIB u8g(...) ... u8g.setColorIndex(1); u8g.drawBox(10, 12, 20, 30); u8g.setColorIndex(0); u8g.drawPixel(28, 14); // clear pixel at (28, 14) See also: drawPixel getColorIndex setDefaultBackgroundColor setContrast C++ Prototype uint8_t U8GLIB::setContrast(uint8_t contast) C Prototype uint8_t u8g_SetContrast(u8g_t *u8g, uint8_t contast) Description Assigns a new contrast value (0..255) to the display. Not all displays or driver support the setting of the contrast value (see devices table). Arguments: u8g : Pointer to the u8g structure (C interface only). contrast: New contrast value (0..255). Returns: The value 1, if the contrast value has been assigned. Use: Inside and outside picture loop. It is a good practice to use this procedure not inside the picture loop. Note: Available with v1.02 Example: See also: Device Table setCursorColor C++ Prototype 

20 . void U8GLIB::setCursorColor(uint8_t fg, uint8_t bg) C Prototype void u8g_SetCursorColor(u8g_t *u8g, uint8_t fg, uint8_t bg) Description Assign the foreground and background color index for the cursor. Arguments: u8g : Pointer to the u8g structure (C interface only). fg: Foreground color index. bg: Background color index. Returns: Use: Outside picture loop. Note: Example: See also: enableCursor setCursorFont C++ Prototype void U8GLIB::setCursorFont(const u8g_pgm_uint8_t *font) C Prototype void u8g_SetCursorFont(u8g_t *u8g, const u8g_pgm_uint8_t *font) Description Set the cursor font (see note below). The cursor shape can be selected from this font. Arguments: u8g : Pointer to the u8g structure (C interface only). font: A pointer to the font data with cursor shapes. Returns: Use: Outside picture loop. Note: The following cursor fonts are available: u8g_font_cursor 

21 . u8g_font_cursorr, reduced number of cursor shapes, uses less memory. Example: See also: setCursorStyle, enableCursor setCursorPos C++ Prototype void U8GLIB::setCursorPos(uint8_t x, uint8_t y) C Prototype void u8g_SetCursorPos(u8g_t *u8g, uint8_t x, uint8_t y) Description Draw the enabled cursor at the specified x/y position. Arguments: u8g : Pointer to the u8g structure (C interface only). x: X-position. y: Y-position. Returns: Use: Outside picture loop. Note: Example: See also: enableCursor setCursorStyle C++ Prototype void U8GLIB::setCursorStyle(uint8_t encoding) C Prototype void u8g_SetCursorStyle(u8g_t *u8g, uint8_t encoding) Description Set the cursor shape. The cursor shape is defined by two bitmaps of a cursor font. The encoding 32 will select the bitmaps 32 and 33 of a cursor font. In the font u8g_font_cursor, this would select the x cursor in the upper left edge: 

22 . Arguments: u8g : Pointer to the u8g structure (C interface only). encoding: A character position within the cursor font. Returns: Use: Outside picture loop. Note: Example: See also: setCursorFont, enableCursor setDefaultBackgroundColor setDefaultForegroundColor setDefaultMidColor C++ Prototype void U8GLIB::setDefaultBackgroundColor(void) void U8GLIB::setDefaultForegroundColor(void) void U8GLIB::setDefaultMidColor(void) C Prototype void u8g_SetDefaultBackgroundColor(u8g_t *u8g) void u8g_SetDefaultForegroundColor(u8g_t *u8g) void u8g_SetDefaultMidColor(u8g_t *u8g) Description Assign one of the default colors as current color index. On a monochrom display, setDefaultBackgroundColor will assign 0 to the current color index and setDefaultForegroundColor will assign 1 to the current color index. For all display types, it is ensured, that setDefaultBackgroundColor and setDefaultForegroundColor will assign different values. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: Use: Inside and outside picture loop. Note: Example: See also: setColorIndex setFont C++ Prototype void U8GLIB::setFont(const u8g_fntpgm_uint8_t *font) C Prototype 

23 . void u8g_SetFont(u8g_t *u8g, const u8g_pgm_uint8_t *font) Description Set the current font and reset the font reference position to "Baseline" (setFontPosBaseline). This font will be used for any further font and draw procedures. U8glib has a lot of built-in fonts which can be used as argument. See here for an overview. Arguments: u8g : Pointer to the u8g structure (C interface only). font: A pointer to the font data. Returns: Use: Inside and outside picture loop. It is a good practice to use this procedure at the beginning of the body of the picture loop. Note: The fonts are loaded into memory as needed. The more fonts you use, the larger your program will be. Example: See also: drawStr setFontPosBaseline setFontLineSpacingFactor C++ Prototype void U8GLIB::setFontLineSpacingFactor(uint8_t factor) C Prototype void u8g_SetFontLineSpacingFactor(u8g_t *u8g,uint8_t factor) Description Assign the factor for the LineSpacing calclation. Line stretch 0.5 0.8 1.0 1.2 1.5 2.0 factor 32 51 64 77 96 128 Arguments: u8g : Pointer to the u8g structure (C interface only). factor: See above. Returns: Use: Inside and outside picture loop. Note: See also: getFontLineSpacing setFontPosBaseline setFontPosBottom setFontPosCenter setFontPosTop C++ Prototype void U8GLIB::setFontPosBaseline(void) void U8GLIB::setFontPosBottom(void) void U8GLIB::setFontPosCenter(void) void U8GLIB::setFontPosTop(void) C Prototype void u8g_SetFontPosBaseline(u8g_t *u8g); void u8g_SetFontPosBottom(u8g_t *u8g); void u8g_SetFontPosCenter(u8g_t *u8g); void u8g_SetFontPosTop(u8g_t *u8g); 

24 . Description Set the reference position for the character and string draw procedure. In the following command u8g_DrawStr(u8g, 5, 20, "ABCdefg"); the string is placed at (5,20), where (5,20) defines the left start of the baseline if setFontPosBaseline has been called (which also is the default). setFontPosBottom: Reference position is getFontDescent() below baseline. setFontPosTop: Reference position is getFontAscent()+1 above baseline (one pixel above the highest refrence character). setFontPosCenter: Reference position centered with respect to getFontAscent() and getFontDescent(). Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: Use: Inside and outside picture loop. Note: Example: setFontPosTop will move the reference point (0,20) for the origin of the text string to the upper left corner of the string. U8GLIB u8g(...) ... u8g.setFont(u8g_font_osb18); u8g.setFontPosTop(); u8g.drawStr(0, 20, "ABC"); See also: drawStr getFontAscent getFontDescent setFontRefHeightAll setFontRefHeightExtendedText setFontRefHeightText C++ Prototype void U8GLIB::setFontRefHeightAll(void) void U8GLIB::setFontRefExtendedHeightText(void) void U8GLIB::setFontRefHeightText(void) C Prototype void u8g_SetFontRefHeightAll(u8g_t *u8g) void u8g_SetFontRefHeightExtendedText(u8g_t *u8g) void u8g_SetFontRefHeightText(u8g_t *u8g) Description A call to one of these procedure will define the calculation method for the ascent and descent of the current font. This method will be used for the current and all other fonts, which will be set with setFont(). Changing this calculation method has an effect on getFontAscent() and getFontDescent(). It has also an effect on the text position methods other than setFontPosBaseline() setFontRefHeightAll: Ascent will be the highest ascent of all glyphs of the current font. Descent will be the highest descent of all glyphs of the current font. setFontRefHeightExtendedText: Ascent will be the largest ascent of "A", "1" or "(" of the current font. Descent will be the descent of "g" or "(" of the current font (this is the default after startup). setFontRefHeightText: Ascent will be the ascent of "A" or "1" of the current font. Descent will be the descent "g" of the current font. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: 

25 . Use: Inside and outside picture loop. Note: Example: setFontRefHeightText: Ascent value of u8g_font_gdr25 is 25. setFontRefHeightExtendedText: Ascent value of u8g_font_gdr25 is 31. setFontRefHeightAll: Ascent value of u8g_font_gdr25 is 35. See also: setFontPosBaseline getFontAscent setHardwareBackup C++ Prototype void U8GLIB::setHardwareBackup(u8g_state_cb backup_cb) C Prototype void u8g_SetHardwareBackup(u8g_t *u8g, u8g_state_cb backup_cb); Description The display can be connected to I/O pins which are also shared with other external devices. Examples are SPI, TWI or UART interfaces. Example: SD card and SPI display share Clock and Data pins (but have different chip select lines). The SD Card software uses the SPI hardware of the microcontroller to access the SD card, but U8glib should use a software SPI mode. In such a case, the hardware state of the microcontroller SPI subsystem must be modified before access to SD card and display. This modification is activated by this procedure. Usage is: (1) Init u8glib, (2) call this procedure and (3) init other libraries. Available backup procedures: u8g_backup_avr_spi: Backup SPI hardware state of an AVR microcontroller. Arguments: u8g : Pointer to the u8g structure (C interface only). backup_cb: Hardware state backup procedure (specific to controller and hardware subsystem). Returns: Use: 

26 . Outside picture loop. Note: Available in v1.05. Example: U8glib uses software SPI and SD library hardware SPI: U8GLIB_DOGM128 u8g(7, 5, 1, 2); // SPI Com: SCK = 7, MOSI = 5, CS = 1, A0 = 2 ... void setup() { ... // SPI backup: Avoid conflict between SW-SPI (u8glib) and HW-SPI (SD) u8g.setHardwareBackup(u8g_backup_avr_spi); ... // Setup Arduino SD library pinMode(SS, OUTPUT); if (SD.begin(23)) { mas_Init(mas_device_sd, NULL); } ... } See also: setPrintPos C++ Prototype void U8GLIB::setPrintPos(u8g_uint_t x, u8g_uint_t y) C Prototype Description Assignes the (x,y) position for the next call of the print procedure. Arguments: x: X-position. y: Y-position. Returns: Use: Inside picture loop. Example: See also: print setRGB C++ Prototype void U8GLIB::setRGB(uint8_t r, uint8_t g, uint8_t b) C Prototype void u8g_SetRGB(u8g_t *u8g, uint8_t r, uint8_t g, uint8_t b) Description Assignes RGB color for one of the color devices. Arguments: u8g : Pointer to the u8g structure (C interface only). r: Red part of the color, range: 0..255. g: Green part of the color, range: 0..255. b: Blue part of the color, range: 0..255. Returns: Note: Available with v1.13 Use: Inside picture loop. 

27 . Example: See also: setColorIndex setRot90 setRot180 setRot270 C++ Prototype void U8GLIB::setRot90() void U8GLIB::setRot180() void U8GLIB::setRot270() C Prototype void u8g_SetRot90(u8g_t *u8g) void u8g_SetRot180(u8g_t *u8g) void u8g_SetRot270(u8g_t *u8g) Description Clockwise rotates the display screen by 90, 180 or 270 degree. For most display devices, landscape view is the default mode. Rotation by 90 or 270 degree will put the display into portrait mode. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: Use: Outside picture loop. Arduino environment: It is a good practice to use this procedure in the setup() procedure. Example: Left: Default landscape mode. Right: Portrait mode with setRot90. See also: undoRotation setScale2x2 C++ Prototype void U8GLIB::setScale2x2() C Prototype void u8g_SetScale2x2(u8g_t *u8g) Description This command halfs x and y dimension of the display. After calling this command, graphics commands output blocks of size 2x2 pixel until a call to u8g:undoScale(). getHeight() and getWidth() only return half of the original display values. All graphic commands between "u8g::setScale2x2()" and "u8g:undoScale()" are scaled up (line draw, pixel set, font, bitmaps, ...). Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: 

28 . Note: Available with v1.09 Use: Outside or inside picture loop. If used inside the picture loop, also call u8g:undoScale() inside the picture loop. Example: void draw(void) { u8g.setFont(u8g_font_unifont); u8g.setFontPosTop(); u8g.drawStr(0, 1, "Hello"); u8g.drawHLine(0, 1+14, 40); u8g.setScale2x2(); // Scale up all draw procedures u8g.drawStr(0, 12, "Hello"); // actual display position is (0,24) u8g.drawHLine(0, 12+14, 40); // All other procedures are also affected u8g.undoScale(); // IMPORTANT: Switch back to normal mode } See also: undoScale sleepOn sleepOff C++ Prototype void U8GLIB::sleepOn(void) void U8GLIB::sleepOff(void) C Prototype void u8g_SleepOn(u8g_t *u8g) void u8g_SleepOff(u8g_t *u8g) Description Enable/disable sleep mode for the display (if possible). Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: - Use: Outside picture loop. Note: Available with v1.11. Supported for ST7565 and SSD13xx controller. Example: undoRotation C++ Prototype void U8GLIB::undoRotation() C Prototype void u8g_UndoRotation(u8g_t *u8g) Description Remove an applied rotation done by the "setRotXY" commands. After calling this command, the display will have its default orientation. Nothing happens if the display has default orientation. 

29 . u8g : Pointer to the u8g structure (C interface only). Returns: Use: Outside picture loop. Example: See also: setRot90 undoScale C++ Prototype void U8GLIB::undoScale() C Prototype void u8g_UndoScale(u8g_t *u8g) Description Remove an applied scaling. If the scaling has been applied within the body of the picture loop, then this command should be called within the body of the picture loop. Arguments: u8g : Pointer to the u8g structure (C interface only). Returns: Note: Available with v1.09 Example: See also: setScale2x2 U8GLIB C++ Prototype void U8GLIB::U8GLIB(u8g_dev_t *dev) void U8GLIB::U8GLIB(u8g_dev_t *dev, uint8_t sck, uint8_t mosi, uint8_t cs, uint8_t a0, uint8_t reset) void U8GLIB::U8GLIB(u8g_dev_t *dev, uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3, uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7 uint8_t en, uint8_t cs1, uint8_t cs2, uint8_t di, uint8_t rw, uint8_t reset) Description Create a new interface to a graphics display. The dev argument describes the type of the display. See here for a complete list of available devices. Usually this constructor is not called directly. Instead there are drived classes for each available device. See also the last column of the device list for a complete list of available constructor calls. Arguments: dev: A pointer to a device structure. Arduino pins: Required pins to connect the display depending on the communication interface. reset: The reset pin is optional and can be U8G_PIN_NONE Returns: Use: Outside picture loop. Note: Example: See also: List of supported devices Comment by cooljian...@gmail.com, Dec 31, 2012 HI，a problem---arduino 12864,when in parallel there are "noises",when in spi ,it's okay,could you tell me why,thanks? Comment by project member olikr...@gmail.com, Dec 31, 2012