MR24HPB1 Human Presence Radar Sensor

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/uart.h"

// MR24HPB1 on UART2: module TX -> GPIO16 (RX2), RX -> GPIO17 (TX2), 9600 baud
#define RADAR_UART UART_NUM_2

void app_main(void)
{
    uart_config_t config = {
        .baud_rate = 9600,
        .data_bits = UART_DATA_8_BITS,
        .parity = UART_PARITY_DISABLE,
        .stop_bits = UART_STOP_BITS_1,
        .flow_ctrl = UART_HW_FLOWCTRL_DISABLE,
    };
    ESP_ERROR_CHECK(uart_param_config(RADAR_UART, &config));
    ESP_ERROR_CHECK(uart_set_pin(RADAR_UART, 17, 16, UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE));
    ESP_ERROR_CHECK(uart_driver_install(RADAR_UART, 1024, 0, 0, NULL, 0));

    uint8_t buf[64];
    while (1) {
        int len = uart_read_bytes(RADAR_UART, buf, sizeof(buf), pdMS_TO_TICKS(200));
        if (len > 0) {
            for (int i = 0; i < len; i++)
                printf("%02X ", buf[i]);
            printf("\n");
        }
    }
}

external_components:
  - source: github://alitheg/esphome-seeed-mr24hpb1@v2.1.0
    components: [seeed_mr24hpb1]

uart:
  id: uart_bus
  tx_pin: GPIO17
  rx_pin: GPIO16
  baud_rate: 9600

seeed_mr24hpb1:
  id: mr24hpb1_radar
  uart_id: uart_bus

binary_sensor:
  - platform: seeed_mr24hpb1
    presence:
      name: "MR24HPB1 Presence"
    motion:
      name: "MR24HPB1 Motion"

text_sensor:
  - platform: seeed_mr24hpb1
    movement_class:
      name: "MR24HPB1 Movement Class"

[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
monitor_speed = 115200

#include <Arduino.h>
// The MR24HPB1 speaks Seeed's binary UART protocol (frames start with 0x55).
// This sketch prints each received frame as hex - decode it with the protocol
// tables in Seeed's MR24HPB1 user manual.

HardwareSerial radar(2); // UART2: sensor TX -> GPIO16 (RX2), RX -> GPIO17 (TX2)

void setup() {
  Serial.begin(115200);
  radar.begin(9600, SERIAL_8N1, 16, 17);
  Serial.println("MR24HPB1 frame monitor");
}

void loop() {
  // Sync on the 0x55 frame header
  if (radar.available() && radar.read() == 0x55) {
    while (radar.available() < 2) {} // wait for the length field
    uint16_t length = radar.read() | (radar.read() << 8); // little-endian, excludes header
    if (length < 3 || length > 32) return; // implausible - resync

    Serial.print("Frame (len ");
    Serial.print(length);
    Serial.print("): 55");
    for (uint16_t i = 0; i < length - 2 && i < 32; i++) {
      while (!radar.available()) {}
      uint8_t b = radar.read();
      Serial.print(" ");
      if (b < 0x10) Serial.print("0");
      Serial.print(b, HEX);
    }
    Serial.println();
  }
}

from machine import UART
import time

# MR24HPB1: module TX -> GPIO16 (RX2), RX -> GPIO17 (TX2), 9600 baud
uart = UART(2, baudrate=9600, tx=17, rx=16)

while True:
    data = uart.read()
    if data:
        print(" ".join("{:02X}".format(b) for b in data))
    time.sleep(0.2)