File content as of revision 4:6a7029bf4e1c:

#include "mbed.h"
#include "RGBLed.h"
#include "PinDetect.h"

DigitalOut myled(p26);
PwmOut builtinLED(LED1);
DigitalIn pb(p22);
//DigitalIn pb2(p21);

// p10 is most significant bit
BusIn ledSelect(p18, p19, p20);

PinName redPin = p24;
PinName greenPin = p25;
PinName bluePin = p23;

PinDetect pb1(p21);
PinDetect pb2(p22);

float volatile p = 1.0f;

void pb1_hit_callback() {
    if (p > 0) {
        p -= 0.1;
    }
}

void pb2_hit_callback() {
    if (p < 0) {
        p += 0.1;
    }
}

int main() {
    
    pb1.mode(PullUp);
    pb2.mode(PullUp);
    wait(0.1);
    
    pb1.attach_asserted(&pb1_hit_callback);
    pb2.attach_asserted(&pb2_hit_callback);
    pb1.setSampleFrequency();
    pb2.setSampleFrequency();
    
    while(1) {
        // Part 1
//        myled = !pb;
        
        // Part 2
//        builtinLED = p;
//        wait(0.5);
        
        // Part 3
        RGBLed myRBGLed = RGBLed(redPin, greenPin, bluePin);
        float redVal = 0.0f;
        float greenVal = 0.0f;
        float blueVal = 0.0f;
        
        if (ledSelect & 0x1) {
            redVal = 1.0 * p;
        }
        if (ledSelect & 0x2) {
            greenVal = 1.0 * p;
        }
        if (ledSelect & 0x4) {
            blueVal = 1.0 * p;
        }

        // Part 4
    }
}