#include "mbed.h"
#include "USBSerial.h"
#include <math.h>

// p5: DIN, p7: CLK, p8: LOAD/CS
SPI max72_spi(p5, NC, p7);
DigitalOut load(p8);
DigitalOut led1(LED1);
DigitalOut led2(LED2);
DigitalOut led3(LED3);
//Virtual serial port over USB
USBSerial serial;
Serial pc(USBTX, USBRX);

int maxInUse = 1;    //change this variable to set how many MAX7219's you'll use
//char ontvangen = 'A';


// 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;
    max72_spi.write(reg);
    max72_spi.write(col);
    load = HIGH;
}

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 ()
{
    // Start of the setup
    // initiation of the max 7219
    // SPI setup: 8 bits, mode 0
    wait_ms(2000);
    led1 = HIGH;
    max72_spi.format(8, 0);
    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);    // the first 0x0f is the value you can set
    wait_ms(2000);
    led1 = LOW;
    // range: 0x00 to 0x0f
    // End of the setup
}
void reset()
{
    for(int i = 1; i <=8; i++) {
        maxSingle(i,0);
    }
}

int main()
{
    setup();
    bool lightUp = false;


    reset();
    // Just a simple test
    // Here I get some problems if the USB is connected, I don't know why.
    // Without the USB everything works fine
    for(int i = 1; i <= 8; i++) {
        for(int j = 0; j < 8; j++) {
            led2 = lightUp;
            maxSingle(i,pow((float)2,(float)j));
            wait_ms(30);
            if((pow((float)2,(float)j)) == 128) {
                maxSingle(i,0);
            }
            lightUp =! lightUp;
        }
    }
    for(int i = 8; i >= 1; i--) {
        for(int j = 8; j >= 0; j--) {
            led2 = lightUp;
            maxSingle(i,pow((float)2,(float)j));
            wait_ms(30);
            if((pow((float)2,(float)j)) == 1) {
                maxSingle(i,0);
            }
            lightUp =! lightUp;
        }
    }

    for(int i = 1; i <= 8; i++) {
        led2 = lightUp;
        maxSingle(i,255);
        wait_ms(50);
        maxSingle(i,0);
        lightUp =! lightUp;
    }
    for(int i = 7; i >= 1; i--) {
        led2 = lightUp;
        maxSingle(i,255);
        wait_ms(50);
        maxSingle(i,0);
        lightUp =! lightUp;
    }
    // End of test

    // Receiving characters from C#
    // This works fine
    while(1) {
        //int ontvangen = serial.getc();
        maxSingle(1,serial.getc());
    }
}