File content as of revision 5:f2820d1efc08:

#include "mbed.h"
#include "Adafruit_LEDBackpack.h"
#include "Adafruit_GFX.h"
 
I2C i2c(D14, D15);

//notes and todos-
//need to make the quad display with text scroll into its own class

//220uA no leds on
//default brightness - rises to 20mA at short peak then back down when scrolling hello
//brightness = 1, rises to ~4mA at short peak then back down when scrolling hello

//mpl - something with stdio screwing things up.  need to define serial port to use for debug
Serial pc (USBTX,USBRX);

Adafruit_16x8matrix matrix = Adafruit_16x8matrix(&i2c);
Adafruit_16x8matrix matrix2 = Adafruit_16x8matrix(&i2c); 

void scrollText(char * buffer, uint8_t buf_len, uint8_t speed);
void showText(char * buffer, uint8_t buf_len, uint8_t duration);

void myidlethread(void);

int main() {

        matrix2.begin(0x71);
        matrix2.setBrightness(1);
        matrix2.setRotation(2);
        
        matrix2.clear();
        matrix2.writeDisplay();
        
        matrix.begin(0x70);
        matrix.setBrightness(1);
                
        matrix.clear();
        matrix.writeDisplay();
        
        char buffer [50];

        sprintf(buffer, "This\0");
        showText(buffer,strlen(buffer), 1);
        sprintf(buffer, "is\0");
        showText(buffer,strlen(buffer), 1);
        sprintf(buffer, "the\0");
        showText(buffer,strlen(buffer), 1);        
        sprintf (buffer, "IoT Lab\0");
        
    while(1)
    {
        scrollText(buffer,strlen(buffer), 100);
        
        Thread::attach_idle_hook (myidlethread);
          
        Thread::wait(10000);
    }

}

void myidlethread(void)
{
  sleep();   //go to sleep, wait for an interrupt 

}


void scrollText(char * buffer, uint8_t buf_len, uint8_t speed)
{
    
    //pc.printf("buffer = %s, len = %d\r\n", buffer, buf_len);
    
    /* code inspired by LOLShield library */
    int xoff=31;/* set offset to the right end of the screen - must be signed*/
    for(int i=0; i< (31 + buf_len*6 +10); i++){ /*scrolling loop*/
         for(int j=0; j<buf_len; j++){ /*loop over all of the chars in the text*/
            if(xoff > 15){
                matrix2.drawChar(xoff + j*6 - 16, 0, buffer[j], 1, 0, 1);

            }else
            {
                matrix.drawChar(xoff + j*6, 0, buffer[j], 1, 0, 1);
                matrix2.drawChar(xoff + j*6 - 16, 0, buffer[j], 1, 0, 1);
            }    
        }
        xoff--; /* decrement x offset*/
        matrix.writeDisplay();
        matrix2.writeDisplay();
        Thread::wait(2000/speed);
        matrix.clear();
        matrix2.clear();
    }    
}    


void showText(char * buffer, uint8_t buf_len, uint8_t duration)
{
     for(int j=0; j<buf_len; j++){ /*loop over all of the chars in the text*/
        matrix.drawChar(j*6, 0, buffer[j], 1, 0, 1);
        matrix2.drawChar(j*6 - 16, 0, buffer[j], 1, 0, 1);
    }
    matrix.writeDisplay();
    matrix2.writeDisplay();
    Thread::wait(1000*duration);
    matrix.clear();
    matrix2.clear();
 
}