hyperion.ng/libsrc/leddevice/LedDeviceSk6812SPI.cpp
penfold42 96037da1cf Added support for sk6812RGBW leds (ab)using the SPI interface. (#61)
right now it only uses RGB - white is set to zero
2016-06-27 22:43:35 +02:00

68 lines
1.5 KiB
C++

// STL includes
#include <cstring>
#include <cstdio>
#include <iostream>
// Linux includes
#include <fcntl.h>
#include <sys/ioctl.h>
// hyperion local includes
#include "LedDeviceSk6812SPI.h"
LedDeviceSk6812SPI::LedDeviceSk6812SPI(const std::string& outputDevice, const unsigned baudrate) :
LedSpiDevice(outputDevice, baudrate, 0),
mLedCount(0),
bitpair_to_byte {
0b10001000,
0b10001100,
0b11001000,
0b11001100,
}
{
// empty
}
int LedDeviceSk6812SPI::write(const std::vector<ColorRgb> &ledValues)
{
mLedCount = ledValues.size();
// 4 colours, 4 spi bytes per colour + 3 frame end latch bytes
#define COLOURS_PER_LED 3
#define SPI_BYTES_PER_COLOUR 4
#define SPI_BYTES_PER_LED COLOURS_PER_LED * SPI_BYTES_PER_COLOUR
unsigned spi_size = mLedCount * SPI_BYTES_PER_LED + 3;
if(_spiBuffer.size() != spi_size){
_spiBuffer.resize(spi_size, 0x00);
}
unsigned spi_ptr = 0;
for (unsigned i=0; i< mLedCount; ++i) {
uint8_t white = 0;
uint32_t colorBits =
((unsigned int)ledValues[i].red << 24) |
((unsigned int)ledValues[i].green << 16) |
((unsigned int)ledValues[i].blue << 8) |
white;
for (int j=SPI_BYTES_PER_LED - 1; j>=0; j--) {
_spiBuffer[spi_ptr+j] = bitpair_to_byte[ colorBits & 0x3 ];
colorBits >>= 2;
}
spi_ptr += SPI_BYTES_PER_LED;
}
_spiBuffer[spi_ptr++] = 0;
_spiBuffer[spi_ptr++] = 0;
_spiBuffer[spi_ptr++] = 0;
return writeBytes(spi_size, _spiBuffer.data());
}
int LedDeviceSk6812SPI::switchOff()
{
return write(std::vector<ColorRgb>(mLedCount, ColorRgb{0,0,0}));
}