How are AVR fonts stored in the program memory area?

Publisher:bln898Latest update time:2020-06-20 Source: eefocusKeywords:AVR Reading articles on mobile phones Scan QR code
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The compiler can use the keyword const to define constants in flash. For example, keil, ICC, etc. define constants using const unsigned char data=0; then the type of data is a constant stored in flash.


The following definition:


typedef struct typFNT_ASC16    


{

    char Index[1];

    char Msk[16];

};

const struct typFNT_ASC16  ASC_16[] =

{    

"1",0x00,0x00,0x08,0x08,0xFC,0x00,0x00,0x00,0x00,0x00,0x04,0x04,0x07,0x04,0x04,0x00,

"2",0x00,0x00,0x08,0x04,0x84,0x44,0x38,0x00,0x00,0x00,0x06,0x05,0x04,0x04,0x04,0x00,

"3",0x00,0x00,0x08,0x04,0x44,0x44,0xB8,0x00,0x00,0x00,0x02,0x04,0x04,0x04,0x03,0x00,

"4",0x00,0x00,0x80,0x60,0x18,0xFC,0x00,0x00,0x00,0x00,0x01,0x01,0x05,0x07,0x05,0x00,

"5",0x00,0x00,0x7C,0x44,0x44,0x44,0x84,0x00,0x00,0x00,0x02,0x04,0x04,0x04,0x03,0x00,

"6",0x00,0x00,0xF0,0x48,0x44,0x44,0x80,0x00,0x00,0x00,0x03,0x04,0x04,0x04,0x03,0x00,

"7",0x00,0x00,0x0C,0x04,0x84,0x64,0x1C,0x00,0x00,0x00,0x00,0x06,0x01,0x00,0x00,0x00,

"8",0x00,0x00,0xB8,0x44,0x44,0x44,0xB8,0x00,0x00,0x00,0x03,0x04,0x04,0x04,0x03,0x00,

"9",0x00,0x00,0x38,0x44,0x44,0x44,0xF8,0x00,0x00,0x00,0x00,0x04,0x04,0x02,0x01,0x00,

"0",0x00,0x00,0xF8,0x04,0x04,0x04,0xF8,0x00,0x00,0x00,0x03,0x04,0x04,0x04,0x03,0x00

};


Just define it as const.


In addition, the flash definition of GCC is quite special. For details, please refer to: http://hi.baidu.com/fujianhuangjia/blog/item/52df50373ce1eff61b4cff13.html


Keywords:AVR Reference address:How are AVR fonts stored in the program memory area?

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