main.cpp

00001 
00002 // show a "progress bar" using the four blue LED
00003 //
00004 // by (85)
00005 
00006 #include "mbed.h"
00007 
00008 PwmOut led1(LED1);
00009 PwmOut led2(LED2);
00010 PwmOut led3(LED3);
00011 PwmOut led4(LED4);
00012 
00013 float done = 0.0;
00014 int mode = 0;
00015 
00016 float zerolim(float a) {
00017     // returns a^2 for a >= 0
00018     return a < 0. ? 0. : a*a;
00019 }
00020 
00021 int main() {
00022     while (1) {
00023         if (!(mode & 1)) {
00024             done += 0.01;
00025             if (done >= 1.1)
00026                 ++mode;
00027         }
00028         if (mode & 1) {
00029             done -= 0.01;
00030             if (done <= -0.1)
00031                 ++mode;
00032         }
00033 /*
00034         // interesting, but not intended
00035         led1 = (done*4)*(done*4);
00036         led2 = (done*4-1)*(done*4-1);
00037         led3 = (done*4-2)*(done*4-2);
00038         led4 = (done*4-3)*(done*4-3);
00039 */
00040 /*
00041         // linear
00042         led1 = done*4;
00043         led2 = done*4-1;
00044         led3 = done*4-2;
00045         led4 = done*4-3;
00046 */        
00047         led1 = zerolim(done*4);
00048         led2 = zerolim(done*4-1);
00049         led3 = zerolim(done*4-2);
00050         led4 = zerolim(done*4-3);
00051         wait(0.01);
00052     }
00053 }