From: Clinton Ebadi <clinton@unknownlamer.org>
Date: Wed, 26 Nov 2014 00:53:49 +0000 (-0500)
Subject: led controller: port to teensy 3.1
X-Git-Url: http://git.hcoop.net/clinton/scratch.git/commitdiff_plain/e732331a7722e334a0f6adc36275206216dff56c

led controller: port to teensy 3.1
 - For now, only target the teensy 3.1.
 - Target full 16-bit pwm (not sure if clock set correctly for full use
   though)
 - Eliminate color correction code
   - Likely wrong anyway
 - Revert to simple text based protocol
   - Teensy I/O is buffered, this is easier
 - Blink random colors when no device has the serial port open
---

diff --git a/arduino_rgb_led/pwm_rgb_led_corrected.ino b/arduino_rgb_led/arduino_rgb_led.ino
similarity index 63%
rename from arduino_rgb_led/pwm_rgb_led_corrected.ino
rename to arduino_rgb_led/arduino_rgb_led.ino
index e9b3c5a..44e6209 100644
--- a/arduino_rgb_led/pwm_rgb_led_corrected.ino
+++ b/arduino_rgb_led/arduino_rgb_led.ino
@@ -14,9 +14,8 @@
 /* You should have received a copy of the GNU General Public License */
 /* along with this program.  If not, see <http://www.gnu.org/licenses/>. */
 
-#include <avr/pgmspace.h>
-#include "gamma.h"
-
+#define DITHER_BITS 1
+const int led_color_max = pow (2, 16) - 1;
 const int dither_steps = pow (2, DITHER_BITS);
 
 typedef struct rgb_pins
@@ -28,10 +27,10 @@ typedef struct rgb_pins
 
 const int rgb_banks = 2;
 
-const rgb_pins pins[rgb_banks] = { {10, 9, 11},
-                                   {5, 6, 3} };
-
-static int led_colors[rgb_banks * 3];
+//const rgb_pins pins[rgb_banks] = { {10, 9, 11},
+//                                   {5, 6, 3} };
+const rgb_pins pins[rgb_banks] = { {9, 6, 10},
+                                   {4, 5, 3} };
 
 void set_color_x (int r, int g, int b, int dither_step = 0)
 {
@@ -39,16 +38,18 @@ void set_color_x (int r, int g, int b, int dither_step = 0)
 
  for (int bank = 0; bank < rgb_banks; bank++)
  {
-   analogWrite (pins[bank].red, pgm_read_byte_near (gammaTable + (r >= 0 ? offset : 0) + r));
-   analogWrite (pins[bank].green, pgm_read_byte_near (gammaTable + (g >= 0 ? offset : 0) + g));
-   analogWrite (pins[bank].blue, pgm_read_byte_near (gammaTable + (b >= 0 ? offset : 0) + b));
+   analogWrite (pins[bank].red, r);
+   analogWrite (pins[bank].green, g);
+   analogWrite (pins[bank].blue, b);
  }
 }
 
 void setup ()
 {
  Serial.begin (115200);
- Serial.setTimeout (100000);
+ Serial.setTimeout (20000);
+ analogWriteResolution (16);
+ randomSeed (analogRead (14));
 
  for (int bank = 0; bank < rgb_banks; bank++)
  {
@@ -58,31 +59,31 @@ void setup ()
  }
 
   // Test sequence to confirm wiring
-  set_color_x (255, 255, 255);
+  set_color_x (led_color_max, led_color_max, led_color_max);
   delay(500);
-  set_color_x (255, 0, 0);
+  set_color_x (led_color_max, 0, 0);
   delay (500);
-  set_color_x (0, 255, 0);
+  set_color_x (0, led_color_max, 0);
   delay (500);
-  set_color_x (0, 0, 255);
+  set_color_x (0, 0, led_color_max);
   delay (500);
 }
 
 void loop ()
 {
-  static int r = 192;
-  static int g = 192;
-  static int b = 192;
+  static int r = led_color_max / 2;
+  static int g = led_color_max / 2;
+  static int b = led_color_max / 2;
   static int step = -1;
   
   //step = (step + 1) % dither_steps;
   step = 0; // dithering is bogus/i'm-not-doing-it-right
 
-  if (Serial.available () >= 3)
+  if (Serial.available ())
     {
-      r = Serial.read ();
-      g = Serial.read ();
-      b = Serial.read ();
+      r = Serial.parseInt ();
+      g = Serial.parseInt ();
+      b = Serial.parseInt ();
 
       Serial.print ("set color ");
       Serial.print (r);
@@ -95,6 +96,13 @@ void loop ()
       set_color_x (r, g, b);
     }
 
+  // display random colors when the serial port is closed
+  if (!Serial.dtr ())
+    {
+      set_color_x (random (led_color_max), random (led_color_max), random (led_color_max));
+      delay (1500);
+    }
+
   set_color_x (r, g, b, step);
 
 }
diff --git a/led-controller.scm b/led-controller.scm
index db55ac9..a417fe2 100644
--- a/led-controller.scm
+++ b/led-controller.scm
@@ -41,6 +41,7 @@
 
 (define color-lock (make-mutex 'recursive))
 (define current-color (vector 0.0 1.0 1.0))
+(define pwm-resolution (1- (expt 2 16)))
 
 (define serial-lock (make-mutex))