hyperion.ng/libsrc/leddevice/LedDeviceWs2812b.cpp

97 lines
2.3 KiB
C++
Raw Normal View History

// Linux includes
#include <unistd.h>
// Local Hyperion-Leddevice includes
#include "LedDeviceWs2812b.h"
LedDeviceWs2812b::LedDeviceWs2812b() :
LedRs232Device("/dev/ttyUSB0", 2000000)
{
// empty
}
int LedDeviceWs2812b::write(const std::vector<ColorRgb> & ledValues)
{
// Ensure the size of the led-buffer
if (_ledBuffer.size() != ledValues.size()*8)
{
_ledBuffer.resize(ledValues.size()*8, ~0x24);
}
// Translate the channel of each color to a signal
uint8_t * signal_ptr = _ledBuffer.data();
for (const ColorRgb & color : ledValues)
{
signal_ptr = color2signal(color, signal_ptr);
}
const int result = writeBytes(_ledBuffer.size(), _ledBuffer.data());
// Official latch time is 50us (lets give it 50us more)
usleep(100);
return result;
}
uint8_t * LedDeviceWs2812b::color2signal(const ColorRgb & color, uint8_t * signal)
{
*signal = bits2Signal(color.red & 0x80, color.red & 0x40, color.red & 0x20);
++signal;
*signal = bits2Signal(color.red & 0x10, color.red & 0x08, color.red & 0x04);
++signal;
*signal = bits2Signal(color.red & 0x02, color.green & 0x01, color.green & 0x80);
++signal;
*signal = bits2Signal(color.green & 0x40, color.green & 0x20, color.green & 0x10);
++signal;
*signal = bits2Signal(color.green & 0x08, color.green & 0x04, color.green & 0x02);
++signal;
*signal = bits2Signal(color.green & 0x01, color.blue & 0x80, color.blue & 0x40);
++signal;
*signal = bits2Signal(color.blue & 0x20, color.blue & 0x10, color.blue & 0x08);
++signal;
*signal = bits2Signal(color.blue & 0x04, color.blue & 0x02, color.blue & 0x01);
++signal;
return signal;
}
int LedDeviceWs2812b::switchOff()
{
// Set all bytes in the signal buffer to zero
for (uint8_t & signal : _ledBuffer)
{
signal = ~0x24;
}
return writeBytes(_ledBuffer.size(), _ledBuffer.data());
}
uint8_t LedDeviceWs2812b::bits2Signal(const bool bit_1, const bool bit_2, const bool bit_3) const
{
// See https://github.com/tvdzwan/hyperion/wiki/Ws2812b for the explanation of the given
// translations
// Bit index(default):1 2 3
// | | |
// default value (1) 00 100 10 (0)
//
// Reversed value (1) 01 001 00 (0)
// | | |
// Bit index (rev): 3 2 1
uint8_t result = 0x24;
if(bit_1)
{
result |= 0x01;
}
if (bit_2)
{
result |= 0x08;
}
if (bit_3)
{
result |= 0x40;
}
return ~result;
}