I am working on a project using the C4001 human presence detection sensor, to which extent I was using the library written by Zhixin Liu.

I m using the DFRobot Firebeetle ESP32S3 with the Arduino framework alongside PlatformIO to add multiple presence detection sensors which would provide us with readings for presence detected within a certain range. I used I2C initially, which worked really well. However, I was unable to get it working with UART for some reason. I made use of the starter code provided with minimal changes made to it. I will attach the code at the end of this post; in case you would like to double check what I have written. In summary, when I open the serial monitor from within VSCode, I don't get any form of output. In fact, this seems to happen whenever I try to call any of the radar's written functions.

Would you be able to advise on what I am doing wrong, so I can fix the associated issues?

Looking forward to hearing from you. Many thanks in advance for your time and consideration.

Kind regards

#include "DFRobot_C4001.h"

//#define I2C_COMMUNICATION //use I2C for communication, but use the serial port for communication if the line of codes were masked

#ifdef I2C_COMMUNICATION

const uint8_t RadarAddress = 0x2A; //default iic_address

/*

* DEVICE_ADDR_1 = 0x2B

*/

DFRobot_C4001_I2C radar(&Wire, RadarAddress);

#else

/* ---------------------------------------------------------------------------------------------------------------------

* board | MCU | Leonardo/Mega2560/M0 | UNO | ESP8266 | ESP32 | microbit | m0 |

* VCC | 3.3V/5V | VCC | VCC | VCC | VCC | X | vcc |

* GND | GND | GND | GND | GND | GND | X | gnd |

* RX | TX | Serial1 TX1 | 5 | 5/D6 | D2 | X | tx1 |

* TX | RX | Serial1 RX1 | 4 | 4/D7 | D3 | X | rx1 |

* ----------------------------------------------------------------------------------------------------------------------*/

/* Baud rate cannot be changed */

#if defined(ARDUINO_AVR_UNO) || defined(ESP8266)

SoftwareSerial mySerial(4, 5);

DFRobot_C4001_UART radar(&mySerial, 9600);

#elif defined(ESP32)

DFRobot_C4001_UART radar1(&Serial1, 9600, /*rx*/ D2, /*tx*/ D3);

#else

DFRobot_C4001_UART radar(&Serial1, 9600);

#endif

#endif

void setup() {

Serial.begin(115200);

delay(2500);

testSerial.begin(9600);

while (!radar.begin()) {

Serial.println("NO Deivces !");

delay(1000);

}

Serial.println("Device connected!");

// speed Mode

radar.setSensorMode(eSpeedMode);

sSensorStatus_t data;

data = radar.getStatus();

// 0 stop 1 start

Serial.print("work status = ");

Serial.println(data.workStatus);

// 0 is exist 1 speed

Serial.print("work mode = ");

Serial.println(data.workMode);

// 0 no init 1 init success

Serial.print("init status = ");

Serial.println(data.initStatus);

Serial.println();

/*

* min Detection range Minimum distance, unit cm, range 0.3~20m (30~2500), not exceeding max, otherwise the function is abnormal.

* max Detection range Maximum distance, unit cm, range 2.4~20m (240~2500)

* thres Target detection threshold, dimensionless unit 0.1, range 0~6553.5 (0~65535)

*/

if (radar.setDetectThres(/*min*/ 11, /*max*/ 1200, /*thres*/ 10)) {

Serial.println("set detect threshold successfully");

}

// set Fretting Detection

radar.setFrettingDetection(eON);

// get confige params

Serial.print("min range = ");

Serial.println(radar.getTMinRange());

Serial.print("max range = ");

Serial.println(radar.getTMaxRange());

Serial.print("threshold range = ");

Serial.println(radar.getThresRange());

Serial.print("fretting detection = ");

Serial.println(radar.getFrettingDetection());

}

void loop() {

Serial.print("target number = ");

Serial.println(radar.getTargetNumber()); // must exist

Serial.print("target Speed = ");

Serial.print(radar.getTargetSpeed());

Serial.println(" m/s");

Serial.print("target range = ");

Serial.print(radar.getTargetRange());

Serial.println(" m");

Serial.print("target energy = ");

Serial.println(radar.getTargetEnergy());

Serial.println();

delay(100);

}