improved backlight dimming parameters

firmware/main.c

@@ -540,22 +540,21 @@ void calculateSpeed(uint8_t updates) {
             // it can get hotter...
             if (callcounter < 8) {
                 speed += 4;
-            } else if (callcounter < 16) {
-                speed += 3;
-            } else if (callcounter < 24) {
-                speed += 2;
             } else {
-                speed += 1;
+                speed += 2;
             }
             setSpeed(speed);
+        } else if (speed < 255) {
+            speed = 255;
+            setSpeed(speed);
         }
         callcounter = 0;
     } else {
         // no key pressed...
         if (callcounter == 16) {
             // ... for a long time, decrease speed value
-            if (speed > 10) {
-                speed -= 10;
+            if (speed > 8) {
+                speed -= 8;
                 setSpeed(speed);
             } else if (speed > 0) {
                 speed = 0;

firmware/modelmayhem.c

@@ -117,8 +117,9 @@ void printMatrix(void) {
 }
 
 void setSpeed(uint8_t speed) {
-    OCR1A = 0xffff - (speed * speed);
-    OCR1B = (speed * speed);
+    uint16_t value = (speed + 1) * (speed + 1) - 1;
+    OCR1A = 0xffff - value;
+    OCR1B = value;
 }
 
 void setLeds(uint8_t LEDstate) {