Diff: main.cpp

Revision:

0:f7be784c668a

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sun Nov 07 00:30:07 2010 +0000
@@ -0,0 +1,53 @@
+
+// show a "progress bar" using the four blue LED
+//
+// by (85)
+
+#include "mbed.h"
+
+PwmOut led1(LED1);
+PwmOut led2(LED2);
+PwmOut led3(LED3);
+PwmOut led4(LED4);
+
+float done = 0.0;
+int mode = 0;
+
+float zerolim(float a) {
+    // returns a^2 for a >= 0
+    return a < 0. ? 0. : a*a;
+}
+
+int main() {
+    while (1) {
+        if (!(mode & 1)) {
+            done += 0.01;
+            if (done >= 1.1)
+                ++mode;
+        }
+        if (mode & 1) {
+            done -= 0.01;
+            if (done <= -0.1)
+                ++mode;
+        }
+/*
+        // interesting, but not intended
+        led1 = (done*4)*(done*4);
+        led2 = (done*4-1)*(done*4-1);
+        led3 = (done*4-2)*(done*4-2);
+        led4 = (done*4-3)*(done*4-3);
+*/
+/*
+        // linear
+        led1 = done*4;
+        led2 = done*4-1;
+        led3 = done*4-2;
+        led4 = done*4-3;
+*/        
+        led1 = zerolim(done*4);
+        led2 = zerolim(done*4-1);
+        led3 = zerolim(done*4-2);
+        led4 = zerolim(done*4-3);
+        wait(0.01);
+    }
+}