👩‍🚒 😽 🐀 我们使用FPGA点亮基于WS2811的LED灯条 🚶🏻 🧑‍🤝‍🧑 🍀

你好。大约两年前，我在速卖通上购买了中文套件，其中包括EasyCycle A2.2调试板和板载Cyclone IV EP4CE6E22C8N，SE-020401红外遥控器，编程器，一对USB电缆和回路。很长一段时间，所有这些东西对我来说都是闲置的。我自己想不到任何有趣且不太费时的任务。

去年，我在同一速卖通上订购了基于著名的WS2811微电路的RGB LED灯带。在购买之前，在查看了YouTube对这些微电路特定协议的评论之后，我认为为FPGA编写自己的驱动器很有趣。由于前面提到的板上有一个光电探测器，那么您还可以使用套件中的遥控器添加单击模式的功能。这样的新年前周末项目。

使用WS2811

实际上，从WS2811的数据表中可以明显看出，该协议非常简单：必须将24位RGB888 MSB优先格式的彩色数据传输到微电路的DIN输出。该微电路将在DOUT引脚上复制接下来的24位接收数据，这使得WS2811可以采用菊花链方式：

WS2811微电路的串行连接图：

DIN . — 1.2 µs 1.3 µs, — 0.5 µs 2.0 µs . — 2.5 µs. 50 µs, OUTR ,OUTG OUTB, .

WS2811:

WS2811 WS2811Transmitter

WS2811Transmitter.sv

module WS2811Transmitter
# (
    CLOCK_SPEED = 50_000_000
)
(
    input clkIN,
    input nResetIN,
    input startIN,
    input [23:0] dataIN,
    output busyOUT,
    output txOUT
);

localparam DIVIDER_100_NS = 10_000_000; // 1 / 0.0000001 = 10000000

reg [4:0]  cnt100ns;
reg [24:0] dataShift;
reg busy;
reg tx;

wire [24:0] dataShifted = (dataShift << 1);
wire clock100ns;

initial begin
    busy = 0;
    tx  = 0;
    cnt100ns = 5'd0;
end

assign busyOUT = busy;
assign txOUT = tx;

ClockDivider #(.VALUE(CLOCK_SPEED / DIVIDER_100_NS)) clock100nsDivider (
    .clkIN(clkIN),
    .nResetIN(busy),
    .clkOUT(clock100ns)
);

always @(negedge clkIN or negedge nResetIN) begin
    if (!nResetIN) begin
        busy <= 0;
        tx  <= 0;
        cnt100ns <= 5'd0;
    end
    else begin
        if (startIN && !busy) begin
            busy <= 1;
            dataShift <= {dataIN, 1'b1};
            tx <= 1;
        end

        if (clock100ns && busy) begin
            cnt100ns <= cnt100ns + 5'd1;
            if (cnt100ns == 5'd4 && !dataShift[24]) begin
                tx <= 0;
            end
            if (cnt100ns == 5'd11 && dataShift[24]) begin
                tx <= 0;
            end
            if (cnt100ns == 5'd24) begin
                cnt100ns <= 5'd0;
                dataShift <= dataShifted;
                if (dataShifted == 25'h1000000) begin
                    busy <= 0;
                end
                else begin
                    tx <= 1;
                end         
            end
        end
    end
end

endmodule

, clock100nsDivider 100 ns, clock100ns cnt100ns . startIN 1, , 1 busyOUT. txOUT , 12 cnt100ns 5 — txOUT . 25 , 24 , busyOUT 0.

, clkIN. , busyOUT.

24 FF0055h WS2811Transmitter:

NEC Infrared Transmission Protocol. 562.5µs 562.5µs. — 562.5µs 1.6875ms . — 9ms 4.5ms . 562.5µs .

: (9ms 4.5ms ), 8 , 8 — , 8 — , 8 562.5µs . LSB-first.

NEC Infrared Transmission :

NEC NecIrReceiver

NecIrReceiver.sv

module NecIrReceiver
# (
    CLOCK_SPEED = 50_000
)
(
    input clkIN,
    input nResetIN,
    input rxIN,
    output dataReceivedOUT,
    output [31:0] dataOUT
);

localparam DIVIDER_281250_NS = 3556; // 562.5µs / 2 = 281.25µs; 1 / 0.00028125 ≈ 3556

reg [23:0] pulseSamplerShift;
reg [33:0] dataShift;
reg [31:0] dataBuffer;
reg [1:0] rxState;
reg rxPositiveEdgeDetect;
reg clock281250nsParity;
reg clock281250nsNReset;

wire clock281250ns;
wire startFrameReceived;
wire dataPacketReceived;

initial begin
    rxState = 2'd0;
    rxPositiveEdgeDetect = 0;
    clock281250nsParity = 0;
    clock281250nsNReset = 0;
    pulseSamplerShift = 24'd0;
    dataShift = 34'd0;
    dataBuffer = 32'd0;
end

assign dataReceivedOUT = rxState[0];
assign dataOUT = dataBuffer;
assign dataPacketReceived = dataShift[32];
assign startFrameReceived = dataShift[33];

ClockDivider #(.VALUE(CLOCK_SPEED / DIVIDER_281250_NS)) clock281250nsDivider (
    .clkIN(clkIN),
    .nResetIN(clock281250nsNReset),
    .clkOUT(clock281250ns)
);

always @(posedge clkIN or negedge nResetIN) begin
    if (!nResetIN) begin
        rxState <= 2'd0;
        rxPositiveEdgeDetect <= 0;
        clock281250nsParity <= 0;
        clock281250nsNReset <= 0;
        pulseSamplerShift <= 24'd0;
        dataShift <= 34'd0;
        dataBuffer <= 32'd0;
    end
    else begin
        case ({dataPacketReceived, rxState[1:0]})
            3'b100 : begin
                dataBuffer[31:0] <= dataShift[31:0];
                rxState <= 2'b11;
            end
            3'b111, 3'b110 : rxState <= 2'b10;
            default : rxState <= 2'd0;
        endcase

        case ({rxIN, rxPositiveEdgeDetect})
            2'b10 : begin
                rxPositiveEdgeDetect <= 1;
                clock281250nsParity <= 0;
                clock281250nsNReset <= 0;
                pulseSamplerShift <= 24'd0;

                case ({startFrameReceived, dataPacketReceived, pulseSamplerShift})
                    26'h0ffff00 : dataShift <= 34'h200000001;
                    26'h2000002 : dataShift <= {1'd1, dataShift[31:0], 1'd0};
                    26'h2000008 : dataShift <= {1'd1, dataShift[31:0], 1'd1};
                    default : dataShift <= 34'd0;
                endcase
            end
            2'b01 : rxPositiveEdgeDetect <= 0;
        endcase

        if (clock281250nsNReset == 0) begin
            clock281250nsNReset <= 1;
        end

        if (clock281250ns) begin
            clock281250nsParity <= ~clock281250nsParity;

            if (!clock281250nsParity) begin
                pulseSamplerShift <= {pulseSamplerShift[22:0], rxIN};
            end
        end
    end
end

endmodule

562.5µs. pulseSamplerShift rxIN 562.5µs. .. , ClockDivider — 281.25µs. clock281250ns clock281250nsParity, . rxPositiveEdgeDetect , pulseSamplerShift , .

00FF0FF0h NecIrReceiver:

Main

Main.sv

module Main
(
    input clkIN,
    input nResetIN,
    input rxIN,
    output txOUT
);

localparam IR_COMMAND_EQ   = 32'h00ff906f;
localparam IR_COMMAND_PLAY = 32'h00ffc23d;
localparam IR_COMMAND_PREV = 32'h00ff22dd;
localparam IR_COMMAND_NEXT = 32'h00ff02fd;
localparam IR_COMMAND_MINS = 32'h00ffe01f;
localparam IR_COMMAND_PLUS = 32'h00ffa857;

localparam UNITS_NUMBER = 100;
localparam PATTERN_COLORS_NUMBER = 128;
localparam PATTERNS_NUMBER = 4;
localparam CLOCK_SPEED = 50_000_000;
localparam UPDATES_PER_SECOND = 20;

reg [$clog2(PATTERNS_NUMBER) - 1:0] patternIndex;
reg [$clog2(PATTERN_COLORS_NUMBER) - 1:0] colorIndex;
reg [$clog2(PATTERN_COLORS_NUMBER) - 1:0] colorIndexShift;
reg colorIndexShiftDirection;
reg [2:0] colorSwapIndex;
reg [$clog2(UNITS_NUMBER) - 1:0] unitCounter;
reg txStart;
reg pause;
reg beginTransmissionDelay;

wire ws2811Busy;
wire beginTransmission;
wire [23:0] colorData;
wire [23:0] colorDataSwapped;
wire [0:$clog2(PATTERNS_NUMBER * PATTERN_COLORS_NUMBER) - 1] colorIndexComputed;
wire irCommandReceived;
wire [31:0] irCommand;
wire rxFiltered;

initial begin
    patternIndex = 0;
    colorIndex = 0;
    colorIndexShift = 0;
    colorIndexShiftDirection = 0;
    colorSwapIndex = 0;
    unitCounter = 0;
    txStart = 0;
    pause = 0;
    beginTransmissionDelay = 0;
end

assign colorIndexComputed = {patternIndex, (colorIndex + colorIndexShift)};

ROM1 rom(
    .clock(clkIN),
    .address(colorIndexComputed),
    .q(colorData)
);

ColorSwap colorSwapper (
    .dataIN(colorData),
    .swapIN(colorSwapIndex),
    .dataOUT(colorDataSwapped)
);

RXMajority3Filter rxInFilter (
    .clockIN(clkIN),
    .nResetIN(nResetIN),
    .rxIN(rxIN),
    .rxOUT(rxFiltered)
);

NecIrReceiver #(.CLOCK_SPEED(CLOCK_SPEED))
    necIrReceiver (
    .clkIN(clkIN),
    .nResetIN(nResetIN),
    .rxIN(~rxFiltered),
    .dataReceivedOUT(irCommandReceived),
    .dataOUT(irCommand)
);

ClockDivider #(.VALUE(CLOCK_SPEED / UPDATES_PER_SECOND))
    beginTransmissionTrigger (
    .clkIN(clkIN),
    .nResetIN(nResetIN),
    .clkOUT(beginTransmission)
);

WS2811Transmitter #(.CLOCK_SPEED(CLOCK_SPEED)) 
    ws2811tx (
    .clkIN(clkIN),
    .nResetIN(nResetIN),
    .startIN(txStart),
    .dataIN(colorDataSwapped),
    .busyOUT(ws2811Busy),
    .txOUT(txOUT)
);

always @(posedge clkIN or negedge nResetIN) begin
    if (!nResetIN) begin
        patternIndex <= 0;
        colorIndex <= 0;
        colorIndexShift <= 0;
        colorIndexShiftDirection <= 0;
        colorSwapIndex <= 0;
        unitCounter <= 0;
        txStart <= 0;
        pause <= 0;
        beginTransmissionDelay <= 0;
    end
    else begin
        if (irCommandReceived) begin
            case (irCommand)
                IR_COMMAND_PLAY : pause <= ~pause;
                IR_COMMAND_EQ   : colorIndexShiftDirection <= ~colorIndexShiftDirection;
                IR_COMMAND_NEXT : patternIndex <= patternIndex + 1;
                IR_COMMAND_PREV : patternIndex <= patternIndex - 1;
                IR_COMMAND_PLUS : colorSwapIndex <= (colorSwapIndex == 3'd5) ? 0 : (colorSwapIndex + 1);
                IR_COMMAND_MINS : colorSwapIndex <= (colorSwapIndex == 0) ? 3'd5 : (colorSwapIndex - 1);
            endcase
        end

        if (beginTransmission) begin
            unitCounter <= UNITS_NUMBER;
            colorIndex <= 0;
            case ({colorIndexShiftDirection, pause})
                2'b10 : colorIndexShift <= colorIndexShift + 1;
                2'b00 : colorIndexShift <= colorIndexShift - 1;
            endcase
            beginTransmissionDelay <= 1;
        end
        else if (beginTransmissionDelay) begin
            beginTransmissionDelay <= 0;
        end
        else if (unitCounter != 0 && !ws2811Busy) begin
            colorIndex <= colorIndex + 1;
            unitCounter <= unitCounter - 1;
            txStart <= 1;
        end
        else begin
            txStart <= 0;
        end
    end
end

endmodule

. “” beginTransmission , . irCommandReceived : , , RGB ColorSwap .

EP4CE6E22C8N , M9K Memory Blocks. , , ROM, 24- . .mif , ROM Megafunction Quartus ROM.v . .mif .sof , .

color_patterns_generator.js Node.js, rom.mif :

color_patterns_generator.js

fs = require("fs");

const MODE_REPEAT = "repeat";
const MODE_STRETCH = "stretch";
const MODE_GRADIENT_STRETCH = "gradient-stretch";

const ROM_FILE_NAME = "rom.mif";
const COLORS_NUM = 128;
const COLORS_PATTERNS = [{
        mode: MODE_GRADIENT_STRETCH,
        colors: [
            0xff0000,
            0xff0000,
            0xff00ff,
            0xff00ff,
            0x0000ff,
            0x0000ff,
            0xff00ff,
            0xff00ff,
            0xffff00,
            0xffff00,
            0x00ffff,
            0x00ffff,
            0x00ff00,
            0x00ff00,
            0xff0000,
        ]
    }, {
        mode: MODE_STRETCH,
        colors: [
            0xff0000,
            0xff0000,
            0xff00ff,
            0xff00ff,
            0x0000ff,
            0x0000ff,
            0xff00ff,
            0xff00ff,
            0xffff00,
            0xffff00,
            0x00ffff,
            0x00ffff,
            0x00ff00,
            0x00ff00,
        ]
    }, {
        mode: MODE_REPEAT,
        colors: [
            0xff0000,
            0xff0000,
            0xff0000,
            0xff0000,
            0xff0000,
            0xff0000,
            0xff0000,
            0xffffff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xffffff,
            0x0000ff,
            0x0000ff,
            0x0000ff,
            0x0000ff,
            0x0000ff,
            0x0000ff,
            0x0000ff,
            0xffffff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xffffff,
            0xffff00,
            0xffff00,
            0xffff00,
            0xffff00,
            0xffff00,
            0xffff00,
            0xffff00,
            0xffffff,
            0x00ffff,
            0x00ffff,
            0x00ffff,
            0x00ffff,
            0x00ffff,
            0x00ffff,
            0x00ffff,
            0xffffff,
            0x00ff00,
            0x00ff00,
            0x00ff00,
            0x00ff00,
            0x00ff00,
            0x00ff00,
            0x00ff00,
            0xffffff,
        ]
    }, {
        mode: MODE_REPEAT,
        colors: [
            0xff0000,
            0xff0000,
            0x00ff00,
            0x00ff00,
            0xffff00,
            0xffff00,
            0xff0000,
            0xff0000,
            0xff0000,
            0x00ff00,
            0x00ff00,
            0x00ff00,
            0xffff00,
            0xffff00,
            0xffff00,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0xff00ff,
            0x00ff00,
            0x00ff00,
            0x00ff00,
            0x00ff00,
            0xffff00,
            0xffff00,
            0xffff00,
            0xffff00,
        ]
    }
];

function getRed(color) {
    return ((color >> 16) & 0xff)
}
function getGreen(color) {
    return ((color >> 8) & 0xff)
}
function getBlue(color) {
    return ((color) & 0xff)
}
function toHex(d) {
    let result = Number(d).toString(16).toUpperCase();
    return result.length % 2 ? "0" + result : result;
}
function generate() {
    let result = "";
    let byteAddress = 0;

    result += "WIDTH = 24;                   -- The size of data in bits\n";
    result += "DEPTH = " + (COLORS_NUM * COLORS_PATTERNS.length) + ";                   -- The size of memory in words\n";
    result += "ADDRESS_RADIX = HEX;          -- The radix for address values\n";
    result += "DATA_RADIX = HEX;             -- The radix for data values\n";
    result += "CONTENT                       -- start of (address : data pairs)\n";
    result += "BEGIN\n";

    let red;
    let green;
    let blue;

    for (let pattern of COLORS_PATTERNS) {
        for (let i = 0; i < COLORS_NUM; i++) {
            if (pattern.mode === MODE_GRADIENT_STRETCH) {
                let index = i * (pattern.colors.length - 1) / COLORS_NUM;
                let colorA = pattern.colors[Math.floor(index)];
                let colorB = pattern.colors[Math.floor(index) + 1];
                let colorBValue = index % 1;
                let colorAValue = 1 - colorBValue;

                red = Math.round(getRed(colorA) * colorAValue + getRed(colorB) * colorBValue);
                green = Math.round(getGreen(colorA) * colorAValue + getGreen(colorB) * colorBValue);
                blue = Math.round(getBlue(colorA) * colorAValue + getBlue(colorB) * colorBValue);
            } else if (pattern.mode === MODE_STRETCH) {
                let index = Math.floor(i * pattern.colors.length / COLORS_NUM);
                let color = pattern.colors[index];

                red = getRed(color);
                green = getGreen(color);
                blue = getBlue(color);
            } else if (pattern.mode === MODE_REPEAT) {
                let index = i % pattern.colors.length;
                let color = pattern.colors[index];

                red = getRed(color);
                green = getGreen(color);
                blue = getBlue(color);
            }

            result +=
                toHex(i + byteAddress) + " : " +
                toHex(red) +
                toHex(green) +
                toHex(blue) + ";\n";
        }

        byteAddress += COLORS_NUM;
    }

    result += "END;";
    return result;
}

try {
    fs.writeFileSync(ROM_FILE_NAME, generate());
    console.log("Success");
} catch (err) {
    console.log("Failed\n", err);
}

GitHub

我们使用FPGA点亮基于WS2811的LED灯条

使用WS2811

WS2811 WS2811Transmitter

NEC NecIrReceiver

Main

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