ESPHome D6T Custom Component

d6t_44l_06.h

#include "esphome.h"
#include "math.h"

using namespace esphome;

#define I2C_ADDR_D6T 0x0a
#define CMD 0x4c

static const int SOBEL_X[3][3] =
    { { -1, 0, 1 },
      { -2, 0, 2 },
      { -1, 0, 1 } };

static const int SOBEL_Y[3][3] =
  { { -1, -2, -1 },
    { 0,  0,  0 },
    { 1,  2,  1 } };

static const float THRESHOLD = 4.0;

class D6T44L06BinarySensor : public PollingComponent, public binary_sensor::BinarySensor {
 public:
  D6T44L06BinarySensor() : PollingComponent(500) {}

  void setup() override {
    Wire.begin();
  }

  void update() override {
    float temps[4][4];
    float gradients[4][4];
    bool state;

    readTemps(temps);
    applySobel(temps, gradients);
    state = meetsThreshold(gradients);

    publish_state(state);
  }

 private:
  void readTemps(float temps[4][4]) {
    uint8_t buf[35];
    int i = 0;

    Wire.beginTransmission(I2C_ADDR_D6T);
    Wire.write(CMD);
    Wire.endTransmission();

    Wire.requestFrom(I2C_ADDR_D6T, 35);
    while (Wire.available() && i < 35){
      buf[i++] = Wire.read();
    }
    Wire.endTransmission();

    for (int y = 0; y < 4; y++) {
      for (int x = 0; x < 4; x++) {
        i = x + (y * 4);
        temps[y][x] = (buf[(i * 2 + 2)] + (buf[(i * 2 + 3)] << 8)) * 0.1;
      }
    }
  }

  void applySobel(float temps[4][4], float gradients[4][4]) {
    for (int y = 0; y < 4; y++) {
      for (int x = 0; x < 4; x++) {
        float magX = 0;
        float magY = 0;
        float gradient = 0;

        for (int yk = 0; yk < 3; yk++) {
          for (int xk = 0; xk < 3; xk++) {
            magX += temps[clamp(y + yk - 1, 0, 3)][clamp(x + xk - 1, 0, 3)] * SOBEL_X[yk][xk];
            magY += temps[clamp(y + yk - 1, 0, 3)][clamp(x + xk - 1, 0, 3)] * SOBEL_Y[yk][xk];
          }
        }

        gradients[y][x] = sqrt(pow(magX, 2) + pow(magY, 2));
      }
    }
  }

  bool meetsThreshold(float values[4][4]) {
    for (int y = 0; y < 4; y++){
      for (int x = 0; x < 4; x++){
        if (values[y][x] >= THRESHOLD) {
          return true;
        }
      }
    }

    return false;
  }

  int clamp(int d, int min, int max) {
    const int t = d < min ? min : d;
    return t > max ? max : t;
  }
};

d6t_sensor.yaml

esphome:
  includes:
    - d6t_44l_06.h
  name: d6t_sensor
  platform: ESP32
  board: nodemcu-32s

i2c:
  sda: 21
  scl: 22
  scan: False

binary_sensor:
- platform: custom
  lambda: |-
    auto d6t_sensor = new D6T44L06BinarySensor();
    App.register_component(d6t_sensor);
    return {d6t_sensor};

  binary_sensors:
    name: "D6T Sensor"
    device_class: occupancy

I just matched the pins via the data sheet. I don't remember it exactly, but it's just power, ground and then the i2c pins on your board. In my case those were pins 21 and 22.

The D6T-1A-01 only has a single output, so you don't need most of the code above. You can probably reuse the connection logic (readTemps), but would need to change the output format and read buffer size (Wire.requestFrom). The rest you can just skip: either you output the temperature directly as a sensor, or you apply some threshold to it.

Hi @mKeRix I'm not so well versed with the libraries. Is it possible to re-write this for D6T-1A? found this arduino code for d6t-1A, but not quite sure how to port it! https://github.com/hankha/d6t-ap-SeatOccupancy-arduino/blob/master/examples/d6t-1a/d6t-1a.ino