initial commit of in-progress platformio/arduino code

fw/HackSpaceCon/src/rgbled.cpp

@@ -0,0 +1,82 @@
+#include <Arduino.h>
+#include "rgbled.h"
+
+
+
+uint8_t rgbp_rainbow(uint8_t init);
+
+uint8_t (*rgb_program[1])(uint8_t) = {
+    rgbp_rainbow
+};
+
+
+
+#define RGB_COUNT	5
+uint8_t rgbled[3 * RGB_COUNT];
+
+
+// configures and enables the 50Hz timer interrupt that is used for RGB program updates
+void conf_rgb_timer()
+{
+    // this timer will run at half speed.
+    // so 8MHz / 2 (prescale) / 1 (CLK_PER) = 4MHz
+    // this will allow a full cycle time of ~61Hz. 
+    
+    _PROTECTED_WRITE(CLKCTRL_MCLKCTRLB, 0); // disable CLK_PER divider
+
+    disable_rgb_timer();
+    
+    TCB0.CTRLA = TCB_CLKSEL_CLKDIV2_gc;     // prescale timer to run at half speed
+    TCB0.CCMP = 0xffff;                     // count to full
+    TCB0.CNT = 0;
+}
+
+ISR(TCB0_INT_vect)
+{
+    // reset the INTFLAGS - necessary on this series
+    uint8_t intflags = TCB0.INTFLAGS;
+    TCB0.INTFLAGS = intflags;
+
+    // we don't care why we interrupted.
+    // we'll now return to executing loop()
+}
+
+
+// rgb program 0: rainbow puke
+#define RAINBOW_HUE_INC     50
+#define RAINBOW_OFFSET      (1536/5)
+#define RAINBOW_TIMEOUT     240
+
+uint16_t rainbow_hue = 0;
+uint16_t rainbow_timeout;
+
+uint8_t rgbp_rainbow(uint8_t init)
+{
+    uint8_t i;
+    uint16_t hue;
+
+    if (init) {
+        rainbow_timeout = RAINBOW_TIMEOUT;
+    }
+
+    if (--rainbow_timeout) {
+        hue = rainbow_hue;
+
+        for (i = 0; i < RGB_COUNT; i++) {
+            hue += RAINBOW_OFFSET;
+            if (hue >= 1536) hue -= 1536;
+
+            // apply color
+            // TODO
+        }
+
+        // move the hue wheel for the next cycle through the program
+        rainbow_hue += RAINBOW_HUE_INC;
+        if (rainbow_hue > 1536) rainbow_hue -= 1536;
+
+        return 1;
+    }
+
+    // done with program
+    return 0;
+}