Development of 24GHz mmWave in XIAO and Arduino | Seeed Studio Wiki

[giscus[bot]]

Development of 24GHz mmWave in XIAO and Arduino | Seeed Studio Wiki

Introduction of how to develop mmWave Sensor on XIAO.

https://wiki.seeedstudio.com/mmwave_for_xiao_arduino/

[Jatin1o1]

How Can i integrate this sensor with esp32 or esp8266 ?

[Austin-beep-beep]

I tried Demo 1. Basic mode output with xiao esp32s3 but im Getting this Error

ELF file SHA256: 805bee0994594d52

Rebooting...
ESP-ROM:esp32s3-20210327
Build:Mar 27 2021
rst:0xc (RTC_SW_CPU_RST),boot:0xb (SPI_FAST_FLASH_BOOT)
Saved PC:0x4037d78a
SPIWP:0xee
mode:DIO, clock div:1
load:0x3fce3808,len:0x44c
load:0x403c9700,len:0xbd8
load:0x403cc700,len:0x2a80
entry 0x403c98d0
Programme Starting!
Sensor Software Version: Guru Meditation Error: Core 1 panic'ed (LoadProhibited). Exception was unhandled.

Core 1 register dump:
PC : 0x42002595 PS : 0x00060a30 A0 : 0x82002631 A1 : 0x3fcebe10
A2 : 0x3fc95318 A3 : 0x3fc95b38 A4 : 0x0000000c A5 : 0x3fcebe6c
A6 : 0xfcfd0102 A7 : 0xfcfd0102 A8 : 0x82002595 A9 : 0x3fcebd90
A10 : 0x00000000 A11 : 0xffffffff A12 : 0xca002c8c A13 : 0xca002c8c
A14 : 0x00001770 A15 : 0x3fcebd90 SAR : 0x0000000a EXCCAUSE: 0x0000001c
EXCVADDR: 0x00000008 LBEG : 0x400570e8 LEND : 0x400570f3 LCOUNT : 0x00000000

Backtrace: 0x42002592:0x3fcebe10 0x4200262e:0x3fcebe50 0x42001765:0x3fcebeb0 0x4200348e:0x3fcebf70

ELF file SHA256: 805bee0994594d52

Rebooting...
ESP-ROM:esp32s3-20210327
Build:Mar 27 2021
rst:0xc (RTC_SW_CPU_RST),boot:0xb (SPI_FAST_FLASH_BOOT)
Saved PC:0x42020afa
SPIWP:0xee

[Nickperillo]

For anyone else struggling to stream relaible data over the serial port, its becuase software serial is not up to the task of reading this sensor.

Its really a shame you decided to use software serial considering there are two hardware serial ports available (XIAO ESP32C3).

I found that sofware serial was not nearly reliable enough. I'm just trying to stream the distance vaules over USB to use as a proximity trigger on a PC. With software serial it freezes up and misses frames frequently. Seems like its not able to read the sensor fast enough.

After a lot of wasted time trying to make software serial work, I wired mine up to use the hardware serial pins on D6 and D7. This works way better!!!
This post is really helpful for utilising all available serial ports if needed:
https://forum.seeedstudio.com/t/how-to-use-serial1-with-xiao-esp32c3/266306

No more stuttering or freezing. Maybe for a future revision consider adding some solder bridge jumpers to the end user can decide if they want hardware or software serial. Software serial is junk for this application.

[emblink]

The latest version of the SoftwareSerial library doesn't even compile in the Arduino IDE. To avoid these issues, it's better to skip using SoftwareSerial and switch to HardwareSerial, which will work much more reliably.
With HardwareSerial, you also don’t need to change the radar’s default baud rate.
However, you should disconnect the XIAO board from the sensor and use wires or a breadboard instead.

For the XIAO C6 board, you can use pins D6 and D7 for hardware serial communication with the radar, which should be connected to the radar's RX and TX pins, respectively. Below is a code sample for setting up HardwareSerial on the XIAO C6 board:

HardwareSerial RadarSerial(0); // Alias for UART0 (Serial0)

// Initialize the radar configuration
Seeed_HSP24 xiao_config(RadarSerial, Serial); // With optional debug serial

void setup() {
Serial.begin(115200); // Initialize USB serial communication
RadarSerial.begin(256000); // Initialize hardware serial on D6, D7 for radar communication
// ... Add the rest of your code here
}

[noelk56]

Hi guys, it seems like there is issue while using software serial. The microcontroller freeze while processing. I have also faced the same issue and find a solution. We know that the mmwave sensor uses HLK LD410 module. They have their own library for this.
below is the working code for esp32.

#if defined(ARDUINO_SAMD_NANO_33_IOT) || defined(ARDUINO_AVR_LEONARDO)
//ARDUINO_SAMD_NANO_33_IOT RX_PIN is D1, TX_PIN is D0 
//ARDUINO_AVR_LEONARDO RX_PIN(RXI) is D0, TX_PIN(TXO) is D1 
#define sensorSerial Serial1
#elif defined(ARDUINO_XIAO_ESP32C3) || defined(ARDUINO_XIAO_ESP32C6)
//RX_PIN is D7, TX_PIN is D6
#define sensorSerial Serial0
#elif defined(ESP32)
//Other ESP32 device - choose available GPIO pins
#define sensorSerial Serial1
#if defined(ARDUINO_ESP32S3_DEV)
#define RX_PIN 18
#define TX_PIN 17
#else
#define RX_PIN 16
#define TX_PIN 17
#endif
#else
#error "This sketch only works on ESP32, Arduino Nano 33IoT, and Arduino Leonardo (Pro-Micro)"
#endif

// User defines
// #define DEBUG_MODE
#define ENHANCED_MODE
#define SERIAL_BAUD_RATE 115200

//Change the communication baud rate here, if necessary
//#define LD2410_BAUD_RATE 256000
#include "MyLD2410.h"

#ifdef DEBUG_MODE
MyLD2410 sensor(sensorSerial, true);
#else
MyLD2410 sensor(sensorSerial);
#endif

unsigned long nextPrint = 0, printEvery = 1000;  // print every second

void printValue(const byte &val) {
  Serial.print(' ');
  Serial.print(val);
}

void printData() {
  Serial.print(sensor.statusString());
  if (sensor.presenceDetected()) {
    Serial.print(", distance: ");
    Serial.print(sensor.detectedDistance());
    Serial.print("cm");
  }
  Serial.println();
  if (sensor.movingTargetDetected()) {
    Serial.print(" MOVING    = ");
    Serial.print(sensor.movingTargetSignal());
    Serial.print("@");
    Serial.print(sensor.movingTargetDistance());
    Serial.print("cm ");
    if (sensor.inEnhancedMode()) {
      Serial.print("\n signals->[");
      sensor.getMovingSignals().forEach(printValue);
      Serial.print(" ] thresholds:[");
      sensor.getMovingThresholds().forEach(printValue);
      Serial.print(" ]");
    }
    Serial.println();
  }
  if (sensor.stationaryTargetDetected()) {
    Serial.print(" STATIONARY= ");
    Serial.print(sensor.stationaryTargetSignal());
    Serial.print("@");
    Serial.print(sensor.stationaryTargetDistance());
    Serial.print("cm ");
    if (sensor.inEnhancedMode()) {
      Serial.print("\n signals->[");
      sensor.getStationarySignals().forEach(printValue);
      Serial.print(" ] thresholds:[");
      sensor.getStationaryThresholds().forEach(printValue);
      Serial.print(" ]");
    }
    Serial.println();
  }
  byte lightLevel = sensor.getLightLevel();
  if (lightLevel) {
    Serial.print("Light level: ");
    Serial.println(lightLevel);
  }
  Serial.println();
}

void setup() {
  Serial.begin(SERIAL_BAUD_RATE);
#if defined(ARDUINO_XIAO_ESP32C3) || defined(ARDUINO_XIAO_ESP32C6) || defined(ARDUINO_SAMD_NANO_33_IOT) || defined(ARDUINO_AVR_LEONARDO)
  sensorSerial.begin(LD2410_BAUD_RATE);
#else
  sensorSerial.begin(LD2410_BAUD_RATE, SERIAL_8N1, RX_PIN, TX_PIN);
#endif
  delay(2000);
  Serial.println(__FILE__);
  if (!sensor.begin()) {
    Serial.println("Failed to communicate with the sensor.");
    while (true) {}
  }

#ifdef ENHANCED_MODE
  sensor.enhancedMode();
#else
  sensor.enhancedMode(false);
#endif

  delay(nextPrint);
}

void loop() {
  if ((sensor.check() == MyLD2410::Response::DATA) && (millis() > nextPrint)) {
    nextPrint = millis() + printEvery;
    printData();
  }
}

[demarinis]

when i try to download the library for mmWave in XIAO and Arduino Github writes "404 this is not the webpage you are looking for." Where is the library now located?

[nfs0619]

Hi, the link issue has been fixed. You should be able to download the library now. Let us know if you need any further help!

[demarinis]

Hi Frank, thanks so much! I am trying to follow your Wiki on using the 24GHz mmWave device with a XIAOESP32C3 exactly I dowloaded the zip file from Github and installed it and tried to compile and run the examples. under the /Examples/Seeed Arduino 24GHz Radar Sensor there are 2 examples MR24FDB1_Example and MR24HPB1_Example i tried both the MR24FDB1_Example compiles and uploads but does Not send back any thing in the Serial monitor window in the Arduino IDE - it just stays blank the MR24HPB1_Example does not compile. There is an error "/private/var/folders/p9/mpmh5j8137lg6p60n7r9pgpw0000gn/T/.arduinoIDE-unsaved202539-5468-fzpqmq.86oer/MR24HPB1_Example/MR24HPB1_Example.ino: In function 'void loop()': /private/var/folders/p9/mpmh5j8137lg6p60n7r9pgpw0000gn/T/.arduinoIDE-unsaved202539-5468-fzpqmq.86oer/MR24HPB1_Example/MR24HPB1_Example.ino:46:13: error: 'Situation_action' was not declared in this scope 46 | if (Situation_action = 1){ | ^~~~~~~~~~~~~~~~ /private/var/folders/p9/mpmh5j8137lg6p60n7r9pgpw0000gn/T/.arduinoIDE-unsaved202539-5468-fzpqmq.86oer/MR24HPB1_Example/MR24HPB1_Example.ino:49:13: error: 'Situation_action' was not declared in this scope 49 | if (Situation_action = 2){ | ^~~~~~~~~~~~~~~~ /private/var/folders/p9/mpmh5j8137lg6p60n7r9pgpw0000gn/T/.arduinoIDE-unsaved202539-5468-fzpqmq.86oer/MR24HPB1_Example/MR24HPB1_Example.ino:52:13: error: 'Situation_action' was not declared in this scope 52 | if (Situation_action = 3){ | ^~~~~~~~~~~~~~~~ /private/var/folders/p9/mpmh5j8137lg6p60n7r9pgpw0000gn/T/.arduinoIDE-unsaved202539-5468-fzpqmq.86oer/MR24HPB1_Example/MR24HPB1_Example.ino:55:13: error: 'Situation_action' was not declared in this scope 55 | if (Situation_action = 4){ | ^~~~~~~~~~~~~~~~ /private/var/folders/p9/mpmh5j8137lg6p60n7r9pgpw0000gn/T/.arduinoIDE-unsaved202539-5468-fzpqmq.86oer/MR24HPB1_Example/MR24HPB1_Example.ino:58:13: error: 'Situation_action' was not declared in this scope 58 | if (Situation_action = 5){ | ^~~~~~~~~~~~~~~~ /private/var/folders/p9/mpmh5j8137lg6p60n7r9pgpw0000gn/T/.arduinoIDE-unsaved202539-5468-fzpqmq.86oer/MR24HPB1_Example/MR24HPB1_Example.ino:61:13: error: 'Situation_action' was not declared in this scope 61 | if (Situation_action = 6){ | ^~~~~~~~~~~~~~~~ exit status 1 Compilation error: 'Situation_action' was not declared in this scope" Looking at the example code it seems that 'Situation_action' would be a variable that is never defined in the example, and looking at the radar.h and radar.cpp library files it is not defined there either. Do you have any suggestions? thanks, Paul

…

________________________________ From: Frank Nie ***@***.***> Sent: Wednesday, April 9, 2025 10:39 PM To: Seeed-Studio/wiki-documents ***@***.***> Cc: Paul DeMarinis ***@***.***>; Comment ***@***.***> Subject: Re: [Seeed-Studio/wiki-documents] Development of 24GHz mmWave in XIAO and Arduino | Seeed Studio Wiki (Discussion #1248) Hi, the link issue has been fixed. You should be able to download the library now. Let us know if you need any further help! — Reply to this email directly, view it on GitHub<#1248 (reply in thread)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/ABZSBKL3NPRTAFOMEY7KPJL2YX7X5AVCNFSM6AAAAABISPJGFSVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTENZYGY4DCNA>. You are receiving this because you commented.

[nfs0619]

Thank you for sharing the details! We’re arranging to reproduce the issue on our side and working on a fix.

I recommend contacting our technical support team at [email protected], as this will help you get faster and more detailed assistance.