Andrea Corrado
/
max7219ledarray
control 8x8 led array using max7219
Fork of mbed_blinky by
main.cpp
- Committer:
- andcor02
- Date:
- 2015-01-20
- Revision:
- 7:1f26417a6f51
- Parent:
- 4:81cea7a352b0
File content as of revision 7:1f26417a6f51:
#include "mbed.h" // p5: DIN, p7: CLK, p8: LOAD/CS SPI max72_spi(p5, NC, p7); DigitalOut load(p8); int maxInUse = 1; //change this variable to set how many MAX7219's you'll use // define max7219 registers #define max7219_reg_noop 0x00 #define max7219_reg_digit0 0x01 #define max7219_reg_digit1 0x02 #define max7219_reg_digit2 0x03 #define max7219_reg_digit3 0x04 #define max7219_reg_digit4 0x05 #define max7219_reg_digit5 0x06 #define max7219_reg_digit6 0x07 #define max7219_reg_digit7 0x08 #define max7219_reg_decodeMode 0x09 #define max7219_reg_intensity 0x0a #define max7219_reg_scanLimit 0x0b #define max7219_reg_shutdown 0x0c #define max7219_reg_displayTest 0x0f #define LOW 0 #define HIGH 1 #define MHZ 1000000 void maxSingle( int reg, int col) { //maxSingle is the "easy" function to use for a //single max7219 load = LOW; // begin max72_spi.write(reg); // specify register max72_spi.write(col); // put data load = HIGH; // make sure data is loaded (on rising edge of LOAD/CS) } void maxAll (int reg, int col) { // initialize all MAX7219's in the system load = LOW; // begin for ( int c=1; c<= maxInUse; c++) { max72_spi.write(reg); // specify register max72_spi.write(col); // put data } load = HIGH; } void maxOne(int maxNr, int reg, int col) { //maxOne is for adressing different MAX7219's, //while having a couple of them cascaded int c = 0; load = LOW; for ( c = maxInUse; c > maxNr; c--) { max72_spi.write(0); // no-op max72_spi.write(0); // no-op } max72_spi.write(reg); // specify register max72_spi.write(col); // put data for ( c=maxNr-1; c >= 1; c--) { max72_spi.write(0); // no-op max72_spi.write(0); // no-op } load = HIGH; } void setup () { // initiation of the max 7219 // SPI setup: 8 bits, mode 0 max72_spi.format(8, 0); // going by the datasheet, min clk is 100ns so theoretically 10MHz should work... // max72_spi.frequency(10*MHZ); maxAll(max7219_reg_scanLimit, 0x07); maxAll(max7219_reg_decodeMode, 0x00); // using an led matrix (not digits) maxAll(max7219_reg_shutdown, 0x01); // not in shutdown mode maxAll(max7219_reg_displayTest, 0x00); // no display test for (int e=1; e<=8; e++) { // empty registers, turn all LEDs off maxAll(e,0); } maxAll(max7219_reg_intensity, 0x0f & 0x0f); // the first 0x0f is the value you can set // range: 0x00 to 0x0f } void loop () { // //if you use just one MAX7219 it should look like this // maxSingle(1,1); // + - - - - - - - // maxSingle(2,2); // - + - - - - - - // maxSingle(3,4); // - - + - - - - - // maxSingle(4,8); // - - - + - - - - // maxSingle(5,16); // - - - - + - - - // maxSingle(6,32); // - - - - - + - - // maxSingle(7,64); // - - - - - - + - // maxSingle(8,128); // - - - - - - - + // // //wait(2); // //if you use more than one MAX7219, it should look like this // // // maxAll(1,1); // + - - - - - - - // maxAll(2,3); // + + - - - - - - // maxAll(3,7); // + + + - - - - - // maxAll(4,15); // + + + + - - - - // maxAll(5,31); // + + + + + - - - // maxAll(6,63); // + + + + + + - - // maxAll(7,127); // + + + + + + + - // maxAll(8,255); // + + + + + + + + // //wait(2); //maxSingle(11, 7); for (int i=0; i<8;i++){ load = LOW; // begin max72_spi.write(i); // specify register max72_spi.write(0xff); // put data load = HIGH; // make sure data is loaded (on rising edge of LOAD/CS) // wait(0.02); } for (int i=8; i>0;i--){ load = LOW; // begin max72_spi.write(i); // specify register max72_spi.write(0x00); // put data load = HIGH; // make sure data is loaded (on rising edge of LOAD/CS) // wait(0.02); } //if you use more then one max7219 the second one should look like this /* maxOne(2,1,1); // + - - - - - - - maxOne(2,2,2); // - + - - - - - - maxOne(2,3,4); // - - + - - - - - maxOne(2,4,8); // - - - + - - - - maxOne(2,5,16); // - - - - + - - - maxOne(2,6,32); // - - - - - + - - maxOne(2,7,64); // - - - - - - + - maxOne(2,8,128); // - - - - - - - + */ // } int main() { setup (); while(1){ loop (); }}