forked from Makuna/NeoPixelBus
140 lines
4.0 KiB
C++
140 lines
4.0 KiB
C++
/*-------------------------------------------------------------------------
|
|
NeoPixel library helper functions for DotStars using SPI hardware (APA102).
|
|
|
|
Written by Michael C. Miller.
|
|
|
|
I invest time and resources providing this open source code,
|
|
please support me by dontating (see https://github.com/Makuna/NeoPixelBus)
|
|
|
|
-------------------------------------------------------------------------
|
|
This file is part of the Makuna/NeoPixelBus library.
|
|
|
|
NeoPixelBus is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU Lesser General Public License as
|
|
published by the Free Software Foundation, either version 3 of
|
|
the License, or (at your option) any later version.
|
|
|
|
NeoPixelBus is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with NeoPixel. If not, see
|
|
<http://www.gnu.org/licenses/>.
|
|
-------------------------------------------------------------------------*/
|
|
|
|
#pragma once
|
|
|
|
#include <SPI.h>
|
|
|
|
class DotStarSpiMethod
|
|
{
|
|
public:
|
|
DotStarSpiMethod(uint16_t pixelCount, size_t elementSize) :
|
|
_sizeData(pixelCount * elementSize),
|
|
_sizeSendBuffer(calcBufferSize(pixelCount * elementSize))
|
|
{
|
|
_sendBuffer = (uint8_t*)malloc(_sizeSendBuffer);
|
|
memset(_sendBuffer, 0, _sizeSendBuffer);
|
|
setEndFrameBytes();
|
|
}
|
|
|
|
~DotStarSpiMethod()
|
|
{
|
|
SPI.end();
|
|
free(_sendBuffer);
|
|
}
|
|
|
|
bool IsReadyToUpdate() const
|
|
{
|
|
return true; // dot stars don't have a required delay
|
|
}
|
|
|
|
#if defined(ARDUINO_ARCH_ESP32)
|
|
void Initialize(int8_t sck, int8_t miso, int8_t mosi, int8_t ss)
|
|
{
|
|
SPI.begin(sck, miso, mosi, ss);
|
|
init();
|
|
}
|
|
#endif
|
|
|
|
void Initialize()
|
|
{
|
|
SPI.begin();
|
|
init();
|
|
}
|
|
|
|
void Update()
|
|
{
|
|
// due to API inconsistencies need to call different methods on SPI
|
|
#if defined(ARDUINO_ARCH_ESP8266) || defined(ARDUINO_ARCH_ESP32)
|
|
SPI.writeBytes(_sendBuffer, _sizeSendBuffer);
|
|
#else
|
|
SPI.transfer(_sendBuffer, _sizeSendBuffer);
|
|
#endif
|
|
}
|
|
|
|
uint8_t* getPixels() const
|
|
{
|
|
return _sendBuffer + _countStartFrame;
|
|
};
|
|
|
|
size_t getPixelsSize() const
|
|
{
|
|
return _sizeData;
|
|
};
|
|
|
|
private:
|
|
const size_t _countStartFrame = 4;
|
|
const size_t _sizeData; // size of actuall pixel data within _sendBuffer
|
|
const size_t _sizeSendBuffer; // Size of '_sendBuffer' buffer below
|
|
|
|
uint8_t* _sendBuffer; // Holds SPI send Buffer, including LED color values
|
|
|
|
void init()
|
|
{
|
|
#if defined(ARDUINO_ARCH_ESP8266)
|
|
SPI.setFrequency(4000000L); // more than 4mhz causes CLK pulse malformation
|
|
#elif defined(ARDUINO_ARCH_ESP32)
|
|
SPI.setFrequency(4000000L); // more than 4mhz causes CLK pulse malformation
|
|
#elif defined(ARDUINO_ARCH_AVR)
|
|
SPI.setClockDivider(SPI_CLOCK_DIV2); // 8 MHz (6 MHz on Pro Trinket 3V)
|
|
#else
|
|
SPI.setClockDivider((F_CPU + 4000000L) / 8000000L); // 8-ish MHz on Due
|
|
#endif
|
|
SPI.setBitOrder(MSBFIRST);
|
|
SPI.setDataMode(SPI_MODE0);
|
|
}
|
|
|
|
size_t calcBufferSize(size_t sizePixels) const
|
|
{
|
|
const size_t countEndFrameBytes = calcEndFrameSize(sizePixels);
|
|
|
|
// start frame + data + end frame
|
|
const size_t bufferSize = _countStartFrame + sizePixels + countEndFrameBytes;
|
|
return bufferSize;
|
|
}
|
|
|
|
size_t calcEndFrameSize(size_t sizePixels) const
|
|
{
|
|
// end frame
|
|
// one bit for every two pixels with no less than 1 byte
|
|
return ((sizePixels / 4) + 15) / 16;
|
|
}
|
|
|
|
void setEndFrameBytes()
|
|
{
|
|
uint8_t* pEndFrame = _sendBuffer + _countStartFrame + _sizeData;
|
|
uint8_t* pEndFrameStop = pEndFrame + calcEndFrameSize(_sizeData);
|
|
while (pEndFrame != pEndFrameStop)
|
|
{
|
|
*pEndFrame++ = 0xff;
|
|
}
|
|
}
|
|
};
|
|
|
|
|
|
|
|
|