网上有很基于PT32的，我这里借鉴他的代码，实现基于arduino下的，烧录到ESP32验证可行。

MT6826S编码器，是MagnTek 麦歌恩公司的一款磁编码器。

这是直接连接到了直流无刷电机上

支持SPI，ABZ通信，这里选择SPI通信。但是千万要注意，编码器的正反面丝印刚好相反，你接那边，就那边的丝印，否则刚好电源引脚是反的，接上ESP32后，发热，可能烧掉ESP32。其他4根线按丝印接上就行。

好，废话不多说，直接上代码：

#include <SPI.h>
#include <math.h>  // Include the math library to use PI

#define READANGLECOMMAND 0xA000
#define READCOMMAND 0x3000
#define WRITECOMMAND 0x6000     
#define TOEEPROMCOMMAND 0xC000
#define WRITEZEROCOMMAND 0x5000     

#define CS_PIN 5  // Define the Chip Select pin

uint16_t RBuf[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
unsigned int Angle = 0;
uint32_t AngleIn21bits = 0;
uint8_t Spi_TxData[4] = {0x83, 0xff, 0xff, 0xff};
uint8_t Spi_pRxData[4] = {0};

// Variables to store previous angle and time for speed calculation
float previousAngle = 0.0;
unsigned long previousTime = 0;

void setup() {
    Serial.begin(115200);           // Initialize UART communication
    SPI.begin();                  // Initialize SPI
    pinMode(CS_PIN, OUTPUT);      // Set the CS pin as output
    digitalWrite(CS_PIN, HIGH);   // Set CS pin high (idle)
}

uint8_t SPI_transfer(uint8_t data) {
    return SPI.transfer(data);
}

// Function to read the angle from the encoder in radians
float ReadAngle() {
    uint32_t register03 = 0, register04 = 0, register05 = 0;
    uint32_t angle = 0;
    uint8_t pTxData[3] = {0, 0, 0}, pRxData[3] = {0, 0, 0};    
    uint16_t reg_addr = 0;

    digitalWrite(CS_PIN, LOW);  // Set CS pin low to start communication

    // Read register 03
    reg_addr = 0x03;
    reg_addr = ((reg_addr & 0x0FFF) | READCOMMAND);
    pTxData[0] = (uint8_t)(reg_addr >> 8);
    pTxData[1] = (uint8_t)(reg_addr >> 0);
    SPI.transfer(pTxData[0]);
    SPI.transfer(pTxData[1]);
    register03 = SPI.transfer(0x00);

    // Read register 04
    reg_addr = 0x04;
    reg_addr = ((reg_addr & 0x0FFF) | READCOMMAND);
    pTxData[0] = (uint8_t)(reg_addr >> 8);
    pTxData[1] = (uint8_t)(reg_addr >> 0);
    SPI.transfer(pTxData[0]);
    SPI.transfer(pTxData[1]);
    register04 = SPI.transfer(0x00);

    // Read register 05
    reg_addr = 0x05;
    reg_addr = ((reg_addr & 0x0FFF) | READCOMMAND);
    pTxData[0] = (uint8_t)(reg_addr >> 8);
    pTxData[1] = (uint8_t)(reg_addr >> 0);
    SPI.transfer(pTxData[0]);
    SPI.transfer(pTxData[1]);
    register05 = SPI.transfer(0x00);

    digitalWrite(CS_PIN, HIGH);  // Set CS pin high to end communication

    angle = ((register03 << 16) | (register04 << 8) | (register05));
    angle >>= 3;  // Adjust the resolution to fit

    float angleInDegrees = angle * 360.0 / 2097152;  // Convert to degrees
    float angleInRadians = angleInDegrees * PI / 180.0;  // Convert degrees to radians
    return angleInRadians;
}

// Function to calculate speed (radians per second)
float CalculateSpeed(float currentAngle, unsigned long currentTime) {
    float angleDifference = currentAngle - previousAngle;
    unsigned long timeDifference = currentTime - previousTime;

    // Handle angle wrap-around for radians (2 * PI is the full rotation in radians)
    if (angleDifference < -PI) {
        angleDifference += 2 * PI;
    } else if (angleDifference > PI) {
        angleDifference -= 2 * PI;
    }

    // Calculate speed in radians per second
    float speed = (angleDifference * 1000.0) / timeDifference;  // timeDifference is in milliseconds, convert to seconds

    // Update previous values for the next calculation
    previousAngle = currentAngle;
    previousTime = currentTime;

    return speed;
}

void loop() {
    // Get the current time
    unsigned long currentTime = millis();

    // Read the current angle in radians
    float currentAngle = ReadAngle();

    // Calculate speed in radians per second
    float speed = CalculateSpeed(currentAngle, currentTime);

    // Print angle and speed
    Serial.print("Angle: ");
    Serial.print(currentAngle, 4);  // Print angle in radians
    Serial.print(" radians, Speed: ");
    Serial.print(speed, 4);  // Print speed in radians per second
    Serial.println(" radians/second");

    delay(200);  // Delay for 200 milliseconds between readings
}

实测，可以获得以弧度表示的角度数据，和速度数据。