max7219
A library for the MAX7219 7 segment 8 digit display with decimals.
An easy to use library that allows you to write to the display, using the DisplayText method.
DisplayText(Text, Justification)
- Text : The text you want to display (8 characters or less, plus up to 8 decimals)
- Justification : Left or right justified. LEFT(0) or RIGHT(1).
e.g.:
max7219.DisplayText("HELLO", LEFT);
Including decimals in the text will automatically take care of decimals like this:
e.g.
max7219.DisplayText("96.78F", RIGHT);
Write to specific digits on the display using the DisplayChar method:
DiaplayChar(Digit, Char, Decimal)
- Digit : represents the digit number 0-7 (Rightmost Digit = 7, Leftmost Digit = 0)
- Char : The character to display
- Decimal : A flag to illuminate the decimal (true/false)
e.g.
max7219.DisplayChar(5, 'L', false);
Create your own fonts and symbols
A font library is included but can be modified by editing the max7219.h file.
*********************************************************************************************************
* LED Segments: a
* ----
* f| |b
* | g |
* ----
* e| |c
* | |
* ---- o dp
* d
* Register bits:
* bit: 7 6 5 4 3 2 1 0
* dp a b c d e f g
*********************************************************************************************************
* Example : The letter 'I' is represented by illuminating LED's 'b' and 'c' (refer above diagram)
* Therfore the binary representation of 'I' is as follows
*
* abcdefg
* 0110000
*
* The table below contains all the binary values for the desired font. New font characters
* can be added or altered as required.
*
* The DP bit is used to switch on the decimal place LED. DP is not included in the below table
* but is added in the register within the libary depending on the content being displayed.
*********************************************************************************************************
static const struct {
char ascii;
char segs;
} MAX7219_Font[] = {
{'A',0b1110111},{'B',0b1111111},{'C',0b1001110},{'D',0b1111110},{'E',0b1001111},{'F',0b1000111},
{'G',0b1011110},{'H',0b0110111},{'I',0b0110000},{'J',0b0111100},{'L',0b0001110},{'N',0b1110110},
{'O',0b1111110},{'P',0b1100111},{'R',0b0000101},{'S',0b1011011},{'T',0b0001111},{'U',0b0111110},
{'Y',0b0100111},{'[',0b1001110},{']',0b1111000},{'_',0b0001000},{'a',0b1110111},{'b',0b0011111},
{'c',0b0001101},{'d',0b0111101},{'e',0b1001111},{'f',0b1000111},{'g',0b1011110},{'h',0b0010111},
{'i',0b0010000},{'j',0b0111100},{'l',0b0001110},{'n',0b0010101},{'o',0b1111110},{'p',0b1100111},
{'r',0b0000101},{'s',0b1011011},{'t',0b0001111},{'u',0b0011100},{'y',0b0100111},{'-',0b0000001},
{' ',0b0000000},{'0',0b1111110},{'1',0b0110000},{'2',0b1101101},{'3',0b1111001},{'4',0b0110011},
{'5',0b1011011},{'6',0b1011111},{'7',0b1110000},{'8',0b1111111},{'9',0b1111011},{'/0',0b0000000},
};