include/lc7981.c File Reference

#include "lc7981.h"

Functions
void	lcd_init (uint8_t mode)
	lcd_init set the to default values.
void	lcd_clear ()
	Clears the display by setting the whole memory to 0.
void	lcd_write_text (char *txt)
	Outputs text in at the current cursor position.
void	lcd_gotoxy (uint8_t x, uint8_t y)
	Set the display cursor to a specific location.
void	lcd_plot_pixel (uint8_t x, uint8_t y, uint8_t set)
	set or unset a pixel at the specified location
void	lcd_plot_bitmap (uint8_t x, uint8_t y, PGM_P bitmap, uint8_t w, uint8_t h)
	This function will plot a bitmap with the upper left corner to the given coordinates.
void	lcd_plot_char (uint8_t x_off, uint8_t y_off, uint8_t c, uint8_t fw, uint8_t fh, PGM_P font)
	Plots a single character in graphicmode.
void	lcd_plot_text (uint8_t x_off, uint8_t y_off, const char *text, uint8_t fw, uint8_t fh, PGM_P font)
	Plots a text using lcd_plot_char.
void	lcd_plot_pgmtext (uint8_t x_off, uint8_t y_off, PGM_P text, uint8_t fw, uint8_t fh, PGM_P font)
	Plots a text using lcd_plot_char.
Variables
uint8_t	lcd_mode
	Currently used mode, can be text or graphic.
uint8_t	lcd_curline
	Current line. Used for scrolling in text mode.

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Function Documentation

void lcd_clear

(

void

)

Clears the display by setting the whole memory to 0.

void lcd_gotoxy	(	uint8_t	x,
		uint8_t	y
	)

Set the display cursor to a specific location.

Right now this does only work in text mode, since there's no need for it now in graphics mode.
If the x and y values are to big, the function does nothing.

Parameters:

	x	the horizontal cursorposition (starts at 0)
	y	the vertical cursorposition (starts at 0)

void lcd_init

(

uint8_t

mode

)

lcd_init set the to default values.

Parameters:

mode

LCD_TEXT for text mode and LCD_GRAPHIC for graphic mode

void lcd_plot_bitmap	(	uint8_t	x,
		uint8_t	y,
		PGM_P	bitmap,
		uint8_t	w,
		uint8_t	h
	)

This function will plot a bitmap with the upper left corner to the given coordinates.

If the bitmap doesn't fit on the display at this location, nothing is drawn at all.
Unset pixels are treated as transparent
This function is by far the most tricky piece of code in this project,
don't worry if you don't understand it at first sight.
Actually it just loops bitwise through the bitmap and uses some
nice bit shifting magic to get it anywhere you want.

Parameters:

	x	horizontal position of the bitmap
	y	vertical position of the bitmap
	bitmap	pointer to the bitmap in pgmspace
	w	width of the bitmap
	h	height of the bitmap

This function is dedicated to Greta, one of the most important persons in my life so far.

void lcd_plot_char	(	uint8_t	x_off,
		uint8_t	y_off,
		uint8_t	c,
		uint8_t	fw,
		uint8_t	fh,
		PGM_P	font
	)

Plots a single character in graphicmode.

Each character of the font is stored linewise.
This means for a 8x8 Pixel font the 8 bytes are needed.
The first byte is the first line and the last byte is the last line.
The next 8byte are the next character.

If the position is too close to the display edge so it can't be displayed completely,
It won't be displayed at all.

Parameters:

	x_off	horizontal position of the character
	y_off	vertical position of the character
	c	the character or it's ascii code
	fw	width of the font (we start counting from 0, so a 10px width font will have fw = 9)
	fh	height of the font (we start counting from 0, so a 10px height font will have fh = 9)
	font	pointer to the flash area where the font is stored

void lcd_plot_pgmtext	(	uint8_t	x_off,
		uint8_t	y_off,
		PGM_P	text,
		uint8_t	fw,
		uint8_t	fh,
		PGM_P	font
	)

Plots a text using lcd_plot_char.

Parameters:

	x_off	horizontal position of the character
	y_off	vertical position of the character
	text	flash area where the text is stored
	fw	width of the font (we start counting from 0, so a 10px width font will have fw = 9)
	fh	height of the font (we start counting from 0, so a 10px height font will have fh = 9)
	font	pointer to the flash area where the font is stored

See also:

lcd_plot_char

lcd_plot_text

void lcd_plot_pixel	(	uint8_t	x,
		uint8_t	y,
		uint8_t	set
	)

set or unset a pixel at the specified location

Parameters:

	x	horizontal position of the pixel (starts at 0)
	y	horizontal position of the pixel (starts at 0)
	set	can be PIXEL_ON or PIXEL_OFF

void lcd_plot_text	(	uint8_t	x_off,
		uint8_t	y_off,
		const char *	text,
		uint8_t	fw,
		uint8_t	fh,
		PGM_P	font
	)

Plots a text using lcd_plot_char.

Parameters:

	x_off	horizontal position of the character
	y_off	vertical position of the character
	text	the text that is plotted
	fw	width of the font (we start counting from 0, so a 10px width font will have fw = 9)
	fh	height of the font (we start counting from 0, so a 10px height font will have fh = 9)
	font	pointer to the flash area where the font is stored

See also:

lcd_plot_char

void lcd_write_text

(

char *

txt

)

Outputs text in at the current cursor position.

If a \n occurs in the last line of the display, all the other line will be 'scrolled' up. This function is textmode only. The the second line becomes the first, the third the second and so on ...

Parameters:

txt

the text

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Variable Documentation

uint8_t lcd_curline

Current line. Used for scrolling in text mode.

uint8_t lcd_mode

Currently used mode, can be text or graphic.