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Difference between revisions of "seven-segment display/representing letters"
(bug fix rowspan) |
(Fixed the code section. [Edited by BAREKAT DESIGN SERVICES INC.]) |
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0x7E, 0x30, 0x6D, 0x79, 0x33, 0x5B, 0x5F, 0x70, 0x7F, 0x7B, 0x00, 0x00, | 0x7E, 0x30, 0x6D, 0x79, 0x33, 0x5B, 0x5F, 0x70, 0x7F, 0x7B, 0x00, 0x00, | ||
/* < = > ? @ A B C D E F G */ | /* < = > ? @ A B C D E F G */ | ||
− | 0x00, 0x00, 0x00, 0x00, 0x00, 0x77, | + | 0x00, 0x00, 0x00, 0x00, 0x00, 0x77, 0x1F, 0x4E, 0x3D, 0x4F, 0x47, 0x5E, |
/* H I J K L M N O P Q R S */ | /* H I J K L M N O P Q R S */ | ||
− | 0x37, 0x06, 0x3C, | + | 0x37, 0x06, 0x3C, 0x57, 0x0E, 0x55, 0x15, 0x1D, 0x67, 0x73, 0x05, 0x5B, |
/* T U V W X Y Z [ \ ] ^ _ */ | /* T U V W X Y Z [ \ ] ^ _ */ | ||
− | + | 0x0F, 0x3E, 0x1C, 0x5C, 0x13, 0x3B, 0x6D, 0x00, 0x00, 0x00, 0x00, 0x00, | |
/* ` a b c d e f g h i j k */ | /* ` a b c d e f g h i j k */ | ||
− | 0x00, | + | 0x00, 0x77, 0x1F, 0x4E, 0x3D, 0x4F, 0x47, 0x5E, 0x37, 0x06, 0x3C, 0x57, |
/* l m n o p q r s t u v w */ | /* l m n o p q r s t u v w */ | ||
− | + | 0x0E, 0x55, 0x15, 0x1D, 0x67, 0x73, 0x05, 0x5B, 0x0F, 0x3E, 0x1C, 0x5C, | |
/* x y z */ | /* x y z */ | ||
− | + | 0x13, 0x3B, 0x6D | |
}; | }; | ||
const unsigned char seven_seg_digits_decode_gfedcba[75]= { | const unsigned char seven_seg_digits_decode_gfedcba[75]= { | ||
Line 87: | Line 87: | ||
0x3F, 0x06, 0x5B, 0x4F, 0x66, 0x6D, 0x7D, 0x07, 0x7F, 0x6F, 0x00, 0x00, | 0x3F, 0x06, 0x5B, 0x4F, 0x66, 0x6D, 0x7D, 0x07, 0x7F, 0x6F, 0x00, 0x00, | ||
/* < = > ? @ A B C D E F G */ | /* < = > ? @ A B C D E F G */ | ||
− | 0x00, 0x00, 0x00, 0x00, 0x00, 0x77, | + | 0x00, 0x00, 0x00, 0x00, 0x00, 0x77, 0x7C, 0x39, 0x5E, 0x79, 0x71, 0x3D, |
/* H I J K L M N O P Q R S */ | /* H I J K L M N O P Q R S */ | ||
− | 0x76, 0x30, 0x1E, | + | 0x76, 0x30, 0x1E, 0x75, 0x38, 0x55, 0x54, 0x5C, 0x73, 0x67, 0x50, 0x6D, |
/* T U V W X Y Z [ \ ] ^ _ */ | /* T U V W X Y Z [ \ ] ^ _ */ | ||
− | + | 0x78, 0x3E, 0x1C, 0x1D, 0x64, 0x6E, 0x5B, 0x00, 0x00, 0x00, 0x00, 0x00, | |
/* ` a b c d e f g h i j k */ | /* ` a b c d e f g h i j k */ | ||
− | 0x00, | + | 0x00, 0x77, 0x7C, 0x39, 0x5E, 0x79, 0x71, 0x3D, 0x76, 0x30, 0x1E, 0x75, |
/* l m n o p q r s t u v w */ | /* l m n o p q r s t u v w */ | ||
− | + | 0x38, 0x55, 0x54, 0x5C, 0x73, 0x67, 0x50, 0x6D, 0x78, 0x3E, 0x1C, 0x1D, | |
/* x y z */ | /* x y z */ | ||
− | + | 0x64, 0x6E, 0x5B | |
}; | }; | ||
/* Invalid letters are mapped to all segments off (0x00). */ | /* Invalid letters are mapped to all segments off (0x00). */ | ||
unsigned char decode_7seg(unsigned char chr) | unsigned char decode_7seg(unsigned char chr) | ||
− | { /* | + | { /* Implementation uses ASCII */ |
if (chr > (unsigned char)'z') | if (chr > (unsigned char)'z') | ||
return 0x00; | return 0x00; | ||
return seven_seg_digits_decode_abcdefg[chr - '0']; | return seven_seg_digits_decode_abcdefg[chr - '0']; | ||
− | /* or seven_seg_digits_decode_gfedcba */ | + | /* or |
+ | return seven_seg_digits_decode_gfedcba[chr - '0']; */ | ||
} | } | ||
</source> | </source> |
Revision as of 14:55, 26 February 2021
A common method of indicating an error. |
Representing Letters on a Seven-Segment Display, while highly discouraged, have been done mostly in low-end products such as cheap portable media players and many hobby projects. In such places, 7-segment displays were extended to support letters. Those representations varies from implementation to implementation and are not standardized by any standards organization.
Note that some letters such as K (), M (), V (), W (), X (), and Z () are completely unrecognizable by most people and as such been left out of the table below.
Lookup table
One can decode letters to pins via a simple lookup table.
const unsigned char seven_seg_digits_decode_abcdefg[75]= {
/* 0 1 2 3 4 5 6 7 8 9 : ; */
0x7E, 0x30, 0x6D, 0x79, 0x33, 0x5B, 0x5F, 0x70, 0x7F, 0x7B, 0x00, 0x00,
/* < = > ? @ A B C D E F G */
0x00, 0x00, 0x00, 0x00, 0x00, 0x77, 0x1F, 0x4E, 0x3D, 0x4F, 0x47, 0x5E,
/* H I J K L M N O P Q R S */
0x37, 0x06, 0x3C, 0x57, 0x0E, 0x55, 0x15, 0x1D, 0x67, 0x73, 0x05, 0x5B,
/* T U V W X Y Z [ \ ] ^ _ */
0x0F, 0x3E, 0x1C, 0x5C, 0x13, 0x3B, 0x6D, 0x00, 0x00, 0x00, 0x00, 0x00,
/* ` a b c d e f g h i j k */
0x00, 0x77, 0x1F, 0x4E, 0x3D, 0x4F, 0x47, 0x5E, 0x37, 0x06, 0x3C, 0x57,
/* l m n o p q r s t u v w */
0x0E, 0x55, 0x15, 0x1D, 0x67, 0x73, 0x05, 0x5B, 0x0F, 0x3E, 0x1C, 0x5C,
/* x y z */
0x13, 0x3B, 0x6D
};
const unsigned char seven_seg_digits_decode_gfedcba[75]= {
/* 0 1 2 3 4 5 6 7 8 9 : ; */
0x3F, 0x06, 0x5B, 0x4F, 0x66, 0x6D, 0x7D, 0x07, 0x7F, 0x6F, 0x00, 0x00,
/* < = > ? @ A B C D E F G */
0x00, 0x00, 0x00, 0x00, 0x00, 0x77, 0x7C, 0x39, 0x5E, 0x79, 0x71, 0x3D,
/* H I J K L M N O P Q R S */
0x76, 0x30, 0x1E, 0x75, 0x38, 0x55, 0x54, 0x5C, 0x73, 0x67, 0x50, 0x6D,
/* T U V W X Y Z [ \ ] ^ _ */
0x78, 0x3E, 0x1C, 0x1D, 0x64, 0x6E, 0x5B, 0x00, 0x00, 0x00, 0x00, 0x00,
/* ` a b c d e f g h i j k */
0x00, 0x77, 0x7C, 0x39, 0x5E, 0x79, 0x71, 0x3D, 0x76, 0x30, 0x1E, 0x75,
/* l m n o p q r s t u v w */
0x38, 0x55, 0x54, 0x5C, 0x73, 0x67, 0x50, 0x6D, 0x78, 0x3E, 0x1C, 0x1D,
/* x y z */
0x64, 0x6E, 0x5B
};
/* Invalid letters are mapped to all segments off (0x00). */
unsigned char decode_7seg(unsigned char chr)
{ /* Implementation uses ASCII */
if (chr > (unsigned char)'z')
return 0x00;
return seven_seg_digits_decode_abcdefg[chr - '0'];
/* or
return seven_seg_digits_decode_gfedcba[chr - '0']; */
}
Common words
Some of the most commonly used words are shown below:
Hello | Echo | ||||||
On | Off | ||||||
Start | End | Pause | Go | ||||
Up | Loop | ||||||
True | False | ||||||
Push | Pop | ||||||
Error | Ops | Ouch |