hyperion.ng/libsrc/leddevice/LedDeviceWs2812b.h
T. van der Zwan eaa4b0bae5 Added comments to the LedDeviceWs2812b
Former-commit-id: 4314edf59a776f2424d0066c14ba41c7b3162842
2013-12-25 15:37:59 +00:00

77 lines
1.8 KiB
C++

#pragma once
// Hyperion leddevice includes
#include "LedRs232Device.h"
///
/// The LedDevice for controlling a string of WS2812B leds. These are controlled over the mini-UART
/// of the RPi (/dev/ttyAMA0).
///
class LedDeviceWs2812b : public LedRs232Device
{
public:
///
/// Constructs the device (all required parameters are hardcoded)
///
LedDeviceWs2812b();
///
/// Write the color data the the WS2812B led string
///
/// @param ledValues The color data
/// @return Zero on succes else negative
///
virtual int write(const std::vector<ColorRgb> & ledValues);
///
/// Write zero to all leds(that have been written by a previous write operation)
///
/// @return Zero on succes else negative
///
virtual int switchOff();
private:
///
/// Structure holding the four output-bytes corresponding to a single input byte
///
struct ByteSignal
{
uint8_t bit_12;
uint8_t bit_34;
uint8_t bit_56;
uint8_t bit_78;
};
/// Translation table from single input-byte to output-bytes
std::vector<ByteSignal> _byte2signalTable;
///
/// Fills the translation table (_byte2signalTable)
///
void fillTable();
///
/// Computes the output bytes that belong to a given input-byte (no table lookup)
///
/// @param byte The input byte
/// @return The four bytes (ByteSignal) for the output signal
///
ByteSignal byte2Signal(const uint8_t byte) const;
///
/// Translates two bits to a single byte
///
/// @param bit1 The value of the first bit (1=true, zero=false)
/// @param bit1 The value of the ssecond bit (1=true, zero=false)
///
/// @return The output-byte for the given two bit
///
uint8_t bits2Signal(const bool bit1, const bool bit2) const;
///
/// The output buffer for writing bytes to the output
///
std::vector<ByteSignal> _ledBuffer;
};