Revision 0:d18d3df9f06d, committed 2010-11-02

Comitter:

allanw

Date:

Tue Nov 02 01:29:56 2010 +0000

Commit message:

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Tue Nov 02 01:29:56 2010 +0000
@@ -0,0 +1,111 @@
+#include "mbed.h"
+#include <cmath>
+
+#define PERIOD 2000
+
+float analog_avg(AnalogIn ain, int samples);
+float exp_curve(float x, float a);
+void HSVtoRGB( float *r, float *g, float *b, float h, float s, float v );
+
+AnalogIn pot(p20);
+PwmOut red(p23);
+PwmOut green(p21);
+PwmOut blue(p22);
+PwmOut sync(p25);
+DigitalOut out1(p30);
+
+int main() {
+    int period = PERIOD;
+    float r, g, b;
+    
+    red.period_us(period);
+    green.period_us(period);
+    blue.period_us(period);
+    sync.period_us(period);
+    sync.pulsewidth_us(period/2);
+    while (1) {
+        /*float h = pot * 360.0f;
+        HSVtoRGB(&r, &g, &b, h, 1, 0.1);
+        red.pulsewidth_us(r * PERIOD);
+        green.pulsewidth_us(g * PERIOD);
+        blue.pulsewidth_us(b * PERIOD);*/
+        
+        for (float h = 0; h < 360; h += 0.1) {
+            out1 = 1;
+            out1 = 0;
+            HSVtoRGB(&r, &g, &b, h, 1, exp_curve(analog_avg(pot,3), 4));
+            
+            red.pulsewidth_us(exp_curve(r,1.5) * PERIOD);
+            green.pulsewidth_us(exp_curve(g,1.5) * PERIOD);
+            blue.pulsewidth_us(exp_curve(b,1.5) * PERIOD);
+            
+            wait_us(1000);
+        }
+    }
+}
+
+float analog_avg(AnalogIn ain, int samples) {
+    int sum = 0;
+    
+    for (int i = 0; i < samples; i++) {
+        sum += ain.read_u16();
+    }
+    
+    return (sum / samples) / ((float)0xFFFF);
+}    
+    
+// returns a value between 0.0 and 1.0 for an input x of 0.0 to 1.0
+// a affects how "exponential" this curve will be
+float exp_curve(float x, float a) {
+    return (exp(x*a)-1)/(exp(a) - 1);
+}
+
+
+void HSVtoRGB( float *r, float *g, float *b, float h, float s, float v )
+{
+	int i;
+	float f, p, q, t;
+	if( s == 0 ) {
+		// achromatic (grey)
+		*r = *g = *b = v;
+		return;
+	}
+	h /= 60;			// sector 0 to 5
+	i = floor( h );
+	f = h - i;			// factorial part of h
+	p = v * ( 1 - s );
+	q = v * ( 1 - s * f );
+	t = v * ( 1 - s * ( 1 - f ) );
+	switch( i ) {
+		case 0:
+			*r = v;
+			*g = t;
+			*b = p;
+			break;
+		case 1:
+			*r = q;
+			*g = v;
+			*b = p;
+			break;
+		case 2:
+			*r = p;
+			*g = v;
+			*b = t;
+			break;
+		case 3:
+			*r = p;
+			*g = q;
+			*b = v;
+			break;
+		case 4:
+			*r = t;
+			*g = p;
+			*b = v;
+			break;
+		default:		// case 5:
+			*r = v;
+			*g = p;
+			*b = q;
+			break;
+	}
+}
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Tue Nov 02 01:29:56 2010 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/e2ac27c8e93e