my9221.h

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#pragma once

 
#include "pixeltypes.h"
#include "crgb.h"
#include "eorder.h"
#include "fl/stl/noexcept.h"
#include "fl/system/fastpin.h"
#include "fl/system/delay.h"

//
// MY9221 definition - dual-edge (DDR) clocked 12-channel driver
//

template <int DATA_PIN, fl::u8 CLOCK_PIN, EOrder RGB_ORDER = RGB, fl::u32 SPI_SPEED = DATA_RATE_MHZ(1)>
class MY9221Controller : public CPixelLEDController<RGB_ORDER> {
    typedef fl::FastPin<DATA_PIN> DataPin;
    typedef fl::FastPin<CLOCK_PIN> ClockPin;

    static constexpr fl::u16 kCommandWord = 0x0010;

    static constexpr fl::u32 kLatchDelayUs = 230;
 
    FASTLED_FORCE_INLINE void writeBit(fl::u8 bit) {
        if (bit) {
            DataPin::hi();
        } else {
            DataPin::lo();
        }
        // Dual-edge: one toggle clocks one bit.
        ClockPin::toggle();
    }

    void sendWord(fl::u16 data) {
        for (int i = 0; i < 16; ++i) {
            writeBit((data & 0x8000) ? 1 : 0);
            data = static_cast<fl::u16>(data << 1);
        }
    }
 
    void sendLed(fl::u8 c0, fl::u8 c1, fl::u8 c2) {
        sendWord(c0);
        sendWord(c1);
        sendWord(c2);
    }
 
    void latch() {
        ClockPin::lo();
        DataPin::lo();
        fl::delayMicroseconds(kLatchDelayUs);
 
        // Four DI pulses while DCKI is held low.
        for (int i = 0; i < 4; ++i) {
            DataPin::hi();
            DataPin::lo();
        }
    }
 
public:
    MY9221Controller() FL_NO_EXCEPT {}
 
    virtual void init() {
        DataPin::setOutput();
        ClockPin::setOutput();
        DataPin::lo();
        ClockPin::lo();
        (void)SPI_SPEED;
    }
 
protected:
    virtual void showPixels(PixelController<RGB_ORDER> & pixels) {
        // Ensure known idle levels before the first edge.
        DataPin::lo();
        ClockPin::lo();
 
        while (pixels.has(1)) {
            fl::u8 ch[4][3] = {
                {0, 0, 0},
                {0, 0, 0},
                {0, 0, 0},
                {0, 0, 0}
            };
 
            // Map up to 4 CRGB pixels onto one chip: LED0->OUT0 .. LED3->OUT3.
            for (int led = 0; led < 4 && pixels.has(1); ++led) {
                ch[led][0] = pixels.loadAndScale0();
                ch[led][1] = pixels.loadAndScale1();
                ch[led][2] = pixels.loadAndScale2();
                pixels.advanceData();
                pixels.stepDithering();
            }
 
            sendWord(kCommandWord);
 
            // Hardware shift order is OUT3, OUT2, OUT1, OUT0.
            for (int out = 3; out >= 0; --out) {
                sendLed(ch[out][0], ch[out][1], ch[out][2]);
            }
        }
 
        latch();
    }
};