Introduction

This is 200KHz high-frequency ultrasonic ranging sensor with IP65 protection grade. The sensor uses the RS485 interface that follows the standard Modbus-RTU communication protocol, featuring reliable communication. The sensor's slave address and serial port parameter can be revised according to the actual use, so it can be conveniently used with all kinds of industrial controlling machines. In addition, the sensor comes with flexible temperature compensation function that allows users to use the sensor built-in temperature compensation or external temperature compensation according to their needs, which makes it applicable to various complicated application scenarios.

Besides that, the URM14 adopts high-requency and stable ultrasonic transducer that offers 100mm~1500mm effective measuring range for flat reflecting wall, 1mm accuracy, and ±1% error. Compared with the general ultrasonic ranging sensor working at 40 KHZ acoustic frequency, this ranging sensor has higher measurement accuracy and shorter measurement period, which makes it very suitable for high precision and fast response ranging applications. In addition, the sensor has built-in noise level evaluation function, which can realize adaptive ranging in complex scenes. Users can also obtain noise level to optimize the working conditions of the sensor, so as to obtain the highest precision measurement data.

Specification

Board Overview

Pinout

Module Wire Connecting Order:

Register

Register Address Number Name Read/Write Data Range Default Value Data Description
0x00 1 Module PID Register R 0x0000-0xFFFF 0x0002 Product check (Detect module type)
0x01 1 Module VID Register R 0x0000-0xFFFF 0x0010 Version check (0x0010 represents V0.0.1.0)
0x02 1 Module Address Register R/W 0x0001-0x00F7 0x000C When the sensor address is unknown, write to the register through the broadcast address 0x00, at this time, the sensor will not have data output
Save when powered off, take effect after restarting
0x03 1 Serial parameter control register 1 R/W 0x0000-0xFFFF 0x0005 Module Baudrate:
0x0001---2400
0x0003---9600
0x0004---14400
0x0005---19200
0x0006---38400
0x0007---57600
0x0008---115200
Other----115200
Save when powered off, take effect after restarting
0x04 1 Serial parameter control register 2 R/W 0x0000-0xFFFF 0x0001 Module check bit H:  Stop bit L:
0x00---None     0x00---0.5byte
0x01---Even       0x01---1byte
0x02---Odd      0x02---1.5byte
other---none     0x03---2byte
            Other---1byte
Save when powered off, take effect after restarting
0x05 1 Distance register R 0x0000-0xFFFF 0xFFFF The distance value LSB measured by the module represents 0.1mm
0x06 1 Onboard temperature data register R 0x0000-0xFFFF 0x0000 The temperature value LSB measured by the onboard temperature sensor represents 0.1℃ (with unit symbol)
0x07 1 External temperature compensation data register R/W 0x0000-0xFFFF 0x0000 Write ambient temperature data to this register for external temperature compensation, LSB represents 0.1℃ (with unit symbol)
0x08 1 Control register R/W 0x0000-0xFFFF 0x0004 bit0:
0-use onboard temperature compensation function
1-use external temperature compensation function(Users need to write temperature data to external temperature compensation data register)
bit1:
0-enable temperature compensation function
1-disable temperature compensation function
bit2:
0-auto detection
1-passive detection
bit3:
In passive detection mode, write 1 to this bit, then it will measure distance once. The distance value can be read from distance register about 30ms later. This bit is reserved in passive detection mode.
This bit will be auto cleared when set to 1
Save when powered off, take effect after restarting
0x09 1 Electrical noise level register R 0x0000-0x0A 0x0000 0x0000-0x000A corresponds to noise level 0 to 10.
This parameter can show the effect of power supply and environment on the sensor. The smaller the noise level, the more accurate the distance value detected by the sensor.

SEN0358 Register Read/Write Tutorial

Requirements

Library Manager

Connection Diagram

Hardware Connection

Read the detected distance

/**************************************************************************************************************
     This code tests the range finder function of the URM14 ultrasonic sensor
     @ author : roker.wang@dfrobot.com
     @ data   : 11.08.2020
     @ version: 1.0
**************************************************************************************************************/
#include <ArduinoModbus.h>
#include <ArduinoRS485.h>

#define   SLAVE_ADDR                ((uint16_t)0x0C)

#define   TEMP_CPT_SEL_BIT          ((uint16_t)0x01)
#define   TEMP_CPT_ENABLE_BIT       ((uint16_t)0x01 << 1)
#define   MEASURE_MODE_BIT          ((uint16_t)0x01 << 2)
#define   MEASURE_TRIG_BIT          ((uint16_t)0x01 << 3)


typedef enum{ 
  ePid,
  eVid,
  eAddr,
  eComBaudrate,
  eComParityStop,
  eDistance,
  eInternalTempreture,
  eExternTempreture,
  eControl,
  eNoise
}eRegIndex_t;//Sensor register index

/*
 *@brief Read data from holding register of client
 *
 *@param addr : Address of Client
 *@param reg: Reg index
 *@return data if execute successfully, false oxffff.
 */
uint16_t readData(uint16_t addr, eRegIndex_t reg)
{
  uint16_t data;
  if (!ModbusRTUClient.requestFrom(addr, HOLDING_REGISTERS, reg, 1)){
    Serial.print("failed to read registers! ");
    Serial.println(ModbusRTUClient.lastError());
    data = 0xffff;
  }else{
    data =  ModbusRTUClient.read();
  }
  return data;
}

/*
 *@brief write data to holding register of client 
 *
 *@param addr : Address of Client
 *@param reg: Reg index
 *@param data: The data to be written
 *@return 1 if execute successfully, false 0.
 */
uint16_t writeData(uint16_t addr, eRegIndex_t reg, uint16_t data)
{
  if (!ModbusRTUClient.holdingRegisterWrite(addr, reg, data)){
    Serial.print("Failed to write coil! ");
    Serial.println(ModbusRTUClient.lastError());
    return 0;
  }else
    return 1;
}

float  dist;
volatile uint16_t cr = 0;
void setup() {
  ModbusRTUClient.begin(19200);
  Serial.begin(9600);
  cr |= MEASURE_MODE_BIT;//Set bit2 , Set to trigger mode
  cr &= ~(uint16_t)TEMP_CPT_SEL_BIT;//Select internal temperature compensation
  cr &= ~(uint16_t)TEMP_CPT_ENABLE_BIT;//enable temperature compensation
  writeData(SLAVE_ADDR, eControl, cr); //Writes the setting value to the control register
  delay(100);
}

void loop() {
  cr |= MEASURE_TRIG_BIT;//Set trig bit
  writeData(SLAVE_ADDR, eControl, cr); //Write the value to the control register and trigger a ranging
  delay(300);//Delay of 300ms(minimum delay should be greater than 30ms) is to wait for the completion of ranging
  dist = (float)readData(SLAVE_ADDR, eDistance) / 10;//Read distance register, one LSB is 0.1mm

  Serial.print("distance = ");
  Serial.print(dist, 1);
  Serial.println("mm");
}

Read Distance

Read Onboard Temperature

/**************************************************************************************************************
     This code tests the temperature measurement function of the URM14 ultrasonic sensor
     @ author : roker.wang@dfrobot.com
     @ data   : 11.08.2020
     @ version: 1.0
     RX(TTL-RS485转接板) -> TX1/D1 (Arduino Leonardo)  TX(TTL-RS485转接板)-> RX1/D0 (Arduino Leonardo)
**************************************************************************************************************/
#include <ArduinoModbus.h>
#include <ArduinoRS485.h>

#define   SLAVE_ADDR                ((uint16_t)0x0C)

#define   TEMP_CPT_SEL_BIT          ((uint16_t)0x01)
#define   TEMP_CPT_ENABLE_BIT       ((uint16_t)0x01 << 1)
#define   MEASURE_MODE_BIT          ((uint16_t)0x01 << 2)
#define   MEASURE_TRIG_BIT          ((uint16_t)0x01 << 3)

typedef enum{ 
  ePid,
  eVid,
  eAddr,
  eComBaudrate,
  eComParityStop,
  eDistance,
  eInternalTempreture,
  eExternTempreture,
  eControl,
  eNoise
}eRegIndex_t;//Sensor register index


/*
 *@brief Read data from holding register of client
 *
 *@param addr : Address of Client
 *@param reg: Reg index
 *@return data if execute successfully, false oxffff.
 */
uint16_t readData(uint16_t addr, eRegIndex_t reg)
{
  uint16_t data;
  if (!ModbusRTUClient.requestFrom(addr, HOLDING_REGISTERS, reg, 1)){
    Serial.print("failed to read registers! ");
    Serial.println(ModbusRTUClient.lastError());
    data = 0xffff;
  }else{
    data =  ModbusRTUClient.read();
  }
  return data;
}

/*
 *@brief write data to holding register of client 
 *
 *@param addr : Address of Client
 *@param reg: Reg index
 *@param data: The data to be written
 *@return 1 if execute successfully, false 0.
 */
uint16_t writeData(uint16_t addr, eRegIndex_t reg, uint16_t data)
{
  if (!ModbusRTUClient.holdingRegisterWrite(addr, reg, data)){
    Serial.print("Failed to write coil! ");
    Serial.println(ModbusRTUClient.lastError());
    return 0;
  }else
    return 1;
}

void setup() {
  Serial.begin(9600);
  ModbusRTUClient.begin(19200);
}

volatile float temp;
void loop() {
  temp =  (float)readData(SLAVE_ADDR, eInternalTempreture) / 10.0;//Read the temperature register, one LSB is 0.1℃
  Serial.print("internal tempreture = ");
  Serial.print(temp, 1);
  Serial.println("C");
  delay(500);
}

Read Temperature

Revise Module Address

/**************************************************************************************************************
     This code tests the address modification function of the URM14 ultrasonic sensor
     @ author : roker.wang@dfrobot.com
     @ data   : 11.08.2020
     @ version: 1.0
     RX(TTL-RS485转接板) -> TX1/D1 (Arduino Leonardo)  TX(TTL-RS485转接板)-> RX1/D0 (Arduino Leonardo)
**************************************************************************************************************/
#include <ArduinoModbus.h>
#include <ArduinoRS485.h>

#define   PUBLIC_ADDR               ((uint16_t)0x00)
#define   SLAVE_ADDR                ((uint16_t)0x0C)

#define   TEMP_CPT_SEL_BIT          ((uint16_t)0x01)
#define   TEMP_CPT_ENABLE_BIT       ((uint16_t)0x01 << 1)
#define   MEASURE_MODE_BIT          ((uint16_t)0x01 << 2)
#define   MEASURE_TRIG_BIT          ((uint16_t)0x01 << 3)

typedef enum{ 
  ePid,
  eVid,
  eAddr,
  eComBaudrate,
  eComParityStop,
  eDistance,
  eInternalTempreture,
  eExternTempreture,
  eControl,
  eNoise
}eRegIndex_t;//Sensor register index

/*
 *@brief Read data from holding register of client
 *
 *@param addr : Address of Client
 *@param reg: Reg index
 *@return data if execute successfully, false oxffff.
 */
uint16_t readData(uint16_t addr, eRegIndex_t reg)
{
  uint16_t data;
  if (!ModbusRTUClient.requestFrom(addr, HOLDING_REGISTERS, reg, 1)){
    Serial.print("failed to read registers! ");
    Serial.println(ModbusRTUClient.lastError());
    data = 0xffff;
  }else{
    data =  ModbusRTUClient.read();
  }
  return data;
}

/*
 *@brief write data to holding register of client 
 *
 *@param addr : Address of Client
 *@param reg: Reg index
 *@param data: The data to be written
 *@return 1 if execute successfully, false 0.
 */
uint16_t writeData(uint16_t addr, eRegIndex_t reg, uint16_t data)
{
  if (!ModbusRTUClient.holdingRegisterWrite(addr, reg, data)){
    Serial.print("Failed to write coil! ");
    Serial.println(ModbusRTUClient.lastError());
    return 0;
  }else
    return 1;
}

void setup() {
  Serial.begin(9600);
  ModbusRTUClient.begin(19200);
  delay(3000);
}
volatile uint16_t newAddr, res;
void loop() {
  newAddr = 0x11;
  res = writeData(PUBLIC_ADDR, eAddr, newAddr);//Writes the new address value to the register
  Serial.print("The device address has been modified as ");

  Serial.print(newAddr);
  Serial.println(".please reset the device!");
  while (1);
}

Revise Module Address

Revise Module Baud Rate

/**************************************************************************************************************
     This code tests the baudrate modification function of the URM14 ultrasonic sensor
     @ author : roker.wang@dfrobot.com
     @ data   : 11.08.2020
     @ version: 1.0
     RX(TTL-RS485转接板) -> TX1/D1 (Arduino Leonardo)  TX(TTL-RS485转接板)-> RX1/D0 (Arduino Leonardo)
**************************************************************************************************************/
#include <ArduinoModbus.h>
#include <ArduinoRS485.h>

#define   BAUDRATE_DEFAULT          ((uint32_t)19200)
#define   SLAVE_ADDR                ((uint16_t)0x0C)

#define   TEMP_CPT_SEL_BIT          ((uint16_t)0x01)
#define   TEMP_CPT_ENABLE_BIT       ((uint16_t)0x01 << 1)
#define   MEASURE_MODE_BIT          ((uint16_t)0x01 << 2)
#define   MEASURE_TRIG_BIT          ((uint16_t)0x01 << 3)

typedef enum{ 
  ePid,
  eVid,
  eAddr,
  eComBaudrate,
  eComParityStop,
  eDistance,
  eInternalTempreture,
  eExternTempreture,
  eControl,
  eNoise
}eRegIndex_t;//Sensor register index

/*
 *@brief Read data from holding register of client
 *
 *@param addr : Address of Client
 *@param reg: Reg index
 *@return data if execute successfully, false oxffff.
 */
uint16_t readData(uint16_t addr, eRegIndex_t reg)
{
  uint16_t data;
  if (!ModbusRTUClient.requestFrom(addr, HOLDING_REGISTERS, reg, 1)){
    Serial.print("failed to read registers! ");
    Serial.println(ModbusRTUClient.lastError());
    data = 0xffff;
  }else{
    data =  ModbusRTUClient.read();
  }
  return data;
}

/*
 *@brief write data to holding register of client 
 *
 *@param addr : Address of Client
 *@param reg: Reg index
 *@param data: The data to be written
 *@return 1 if execute successfully, false 0.
 */
uint16_t writeData(uint16_t addr, eRegIndex_t reg, uint16_t data)
{
  if (!ModbusRTUClient.holdingRegisterWrite(addr, reg, data)){
    Serial.print("Failed to write coil! ");
    Serial.println(ModbusRTUClient.lastError());
    return 0;
  }else
    return 1;
}

void setup() {
  Serial.begin(9600);
  ModbusRTUClient.begin(BAUDRATE_DEFAULT);
  delay(3000);
}
volatile uint16_t baudrateIndex, res;
void loop() {

  baudrateIndex = 3;       //0x0001---2400   0x0002---4800 0x0003---9600   0x0004---14400
                           //0x0005---19200  0x0006---38400 0x0007---57600 0x0008---115200 Other----115200
  res = writeData(SLAVE_ADDR, eComBaudrate, baudrateIndex);//Writes the new baud rate value to the corresponding register
  if (res)
    Serial.print("The baudrate has been modified as 9600.please reset the device!");
  while (1);
}

Revise Baud Rate

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