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PWM: Revert always apply dead time

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This commit is contained in:
Will Miles 2024-09-29 10:13:19 -04:00
parent 59deebc961
commit cb8dae1ddb
1 changed files with 4 additions and 6 deletions
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10
wled00/bus_manager.cpp
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@ -573,11 +573,6 @@ void BusPwm::show() {
const unsigned maxBri = (1<<_depth); // possible values: 16384 (14), 8192 (13), 4096 (12), 2048 (11), 1024 (10), 512 (9) and 256 (8) const unsigned maxBri = (1<<_depth); // possible values: 16384 (14), 8192 (13), 4096 (12), 2048 (11), 1024 (10), 512 (9) and 256 (8)
const unsigned bitShift = dithering * 4; // if dithering, _depth is 12 bit but LEDC channel is set to 8 bit (using 4 fractional bits) const unsigned bitShift = dithering * 4; // if dithering, _depth is 12 bit but LEDC channel is set to 8 bit (using 4 fractional bits)
#endif #endif
// add dead time between signals (when using dithering, two full 8bit pulses are required)
// this is needed for 2CH, but also adds some slack for ESP8266 which has less precise
// PWM timing.
const int deadTime = (1+dithering) << bitShift;
// use CIE brightness formula (cubic) to fit (or approximate linearity of) human eye perceived brightness // use CIE brightness formula (cubic) to fit (or approximate linearity of) human eye perceived brightness
// the formula is based on 12 bit resolution as there is no need for greater precision // the formula is based on 12 bit resolution as there is no need for greater precision
// see: https://en.wikipedia.org/wiki/Lightness // see: https://en.wikipedia.org/wiki/Lightness
@ -601,9 +596,12 @@ void BusPwm::show() {
// Phase shifting requires that LEDC timers are synchronised (see setup()). For PWM CCT (and H-bridge) it is // Phase shifting requires that LEDC timers are synchronised (see setup()). For PWM CCT (and H-bridge) it is
// also mandatory that both channels use the same timer (pinManager takes care of that). // also mandatory that both channels use the same timer (pinManager takes care of that).
for (unsigned i = 0; i < numPins; i++) { for (unsigned i = 0; i < numPins; i++) {
unsigned duty = (_data[i] * pwmBri) / 255; unsigned duty = (_data[i] * pwmBri) / 255;
unsigned deadTime = 0;
if (_type == TYPE_ANALOG_2CH && Bus::getCCTBlend() == 0) { if (_type == TYPE_ANALOG_2CH && Bus::getCCTBlend() == 0) {
// add dead time between signals (when using dithering, two full 8bit pulses are required)
deadTime = (1+dithering) << bitShift;
// we only need to take care of shortening the signal at (almost) full brightness otherwise pulses may overlap // we only need to take care of shortening the signal at (almost) full brightness otherwise pulses may overlap
if (_bri >= 254 && duty >= maxBri / 2 && duty < maxBri) { if (_bri >= 254 && duty >= maxBri / 2 && duty < maxBri) {
duty -= deadTime << 1; // shorten duty of larger signal except if full on duty -= deadTime << 1; // shorten duty of larger signal except if full on