rewrote emisar-d4k-3ch to use delta-sigma modulation (PWM + DSM),

which gives much better resolution, especially for the 8-bit channel.
Also...
- set_channel_mode() aborts when going from/to the same channel,
  to avoid unnecessary flicker
- hsv2rgb() uses 16-bit R/G/B and V now
- changed default channel to All
- reduced default channel modes to just A, B, C, and All
- smooth ramp floor defaults to 1/150
- raised level when aux LEDs turn on high during use
  (for better compatibility with red main LEDs)

1 files changed, 7 insertions, 4 deletions

diff --git a/spaghetti-monster/fsm-channels.c b/spaghetti-monster/fsm-channels.c
index 62b608c..cc78536 100644
--- a/spaghetti-monster/fsm-channels.c
+++ b/spaghetti-monster/fsm-channels.c
@@ -9,7 +9,10 @@
 
 #if NUM_CHANNEL_MODES > 1
 void set_channel_mode(uint8_t mode) {
+    if (mode == channel_mode) return;  // abort if nothing to do
+
     uint8_t cur_level = actual_level;
+
     // turn off old LEDs before changing channel
     set_level(0);
 
@@ -85,7 +88,7 @@ void calc_2ch_blend(
 
 
 #ifdef USE_HSV2RGB
-RGB_t hsv2rgb(uint8_t h, uint8_t s, uint8_t v) {
+RGB_t hsv2rgb(uint8_t h, uint8_t s, uint16_t v) {
     RGB_t color;
 
     if (s == 0) {  // grey
@@ -105,11 +108,11 @@ RGB_t hsv2rgb(uint8_t h, uint8_t s, uint8_t v) {
     // calculate graph segments, doing integer multiplication
     // TODO: calculate 16-bit results, not 8-bit
     high    = v;
-    low     = (v * (255 - s)) >> 8;
+    low     = ((uint32_t)v * (255 - s)) >> 8;
     // TODO: use a cosine crossfade instead of linear
     // (because it looks better and feels more natural)
-    falling = (v * (255 - ((s * fpart) >> 8))) >> 8;
-    rising  = (v * (255 - ((s * (255 - fpart)) >> 8))) >> 8;
+    falling = ((uint32_t)v * (255 - ((s * fpart) >> 8))) >> 8;
+    rising  = ((uint32_t)v * (255 - ((s * (255 - fpart)) >> 8))) >> 8;
 
     // default floor
     color.r = low;