Atmel Xplained Evaluation Board ATXMEGAA3BU-XPLD ATXMEGAA3BU-XPLD 데이터 시트

 

8413A-AVR-09/11 

Font support is made available through the gfx_mono_text.c and gfx_mono_text.h 
files, which in turn relies on system font objects from sysfont.c and sysfont.h, allowing 
printing of text from glyph data stored in program memory using progmem.c and 
progmem.h. 

The demo application uses the menu system service, which in turn uses gfx_mono, 
combining primitive drawing and text output to create a simple navigation menu 
system. See the menu system chapter for more information. Each individual 
application uses the library for different purposes, such as text, primitives and 
bitmaps. 

The module 

common.services.gfx_mono.menu

 provides a simple menu system for 

monochrome graphical displays. 

Typical flow of an application using the menu system: 

1. Define 

menu 

structure. 

2. Call 

gfx_mono_menu_init()

. 

3.  Get user input. 
4.  Update menu with user input using function 

gfx_mono_menu_process_key()

. 

5. Interpret 

gfx_mono_menu_process_key()

 return value. 

6.  Go to 3. 

The menu is declared using the 'menu' struct defined in 

gfx_mono_menu.h

. It consists 

of the following members: 

•   

title:

 the title of the menu, shown on the top line of the display 

•   

strings:

 an array of strings, each string defines one line in the menu 

•   

num_elements:

 number of elements (strings) in the menu 

 
In addition you have two members for internal use, which should be initialized to 0: 
•   

current_selection:

 the line currently selected 

•   

current_page:

 the active page 

To initialize the menu system, call the 

gfx_mono_menu_init()

 function. Use a 

reference to the menu 

struct

 as parameter. This function will clear the display and 

draw the menu. 

Before the menu can be updated, input from the user is needed. Methods for getting 
input are not part of the menu module, and must be implemented separately. 

 

As soon as input is available, the menu system is informed using the 

gfx_mono_menu_process_key()

 function. Use a reference to your menu struct and 

the user input key code as parameters.