概 述

URM13是一款开放式单探头超声波测距传感器，支持TRIG脉冲触发测距（兼容SR04）、UART和I2C，传感器可以在三种接口模式间无缝切换。该传感器尺寸紧凑、并且兼容如Arduino、树莓派等各种3.3V或5V主控板，非常方便用户集成和应用，UART模式使用标准Modbus-RTU协议并集成了收发控制输出，可简单通过外接RS485收发器扩展RS485接口。该传感器在保持同类传感器尺寸及重量优势的同时还具有非常出色的测距灵敏度，使得他对于一些低声波反射率的探测目标同样具备超越同类传感器的探测性能。URM13传感器会在每次测距时自动检测环境及电源噪声并以此来动态调节测量参数，确保它能在各种复杂应用场景之下依旧能够稳定工作。
为了满足不同的用户需求，URM13内置两段测距量程：
1、小量程15-150cm：可以实现高达50HZ的高频率探测，适用于室内机器人避障等场景。
2、大量程40-900cm：具有卓越的测量灵敏度，测量频率为常规10HZ，适用于空旷场景或需要高灵敏度、高量程距离探测的场景。
实际使用时，可通过重复触发2段量程的测距，以实现整个量程的检测。

技术参数

• 工作电压：3.3~5.5V DC
• 最大瞬时电流：350mA
• 有效量程：15cm ~ 900cm
• 距离分辨率：1cm
• 距离误差：±1%
• 温度分辨率：0.1℃
• 温度误差：±1℃
• 测量频率：10HZ
• 工作温度：-10℃～＋70℃
• 工作湿度范围：RH<75%
• 传感器声学频率：40±1KHz
• 传感器方向角：60°(-6dB)
• 通信接口：I2C&TRIG/UART(Modbus-RTU)

接口及尺寸

• 尺寸示意图：
  

• 接口描述：
  URM13可以在IIC、UART两种通信接口间任意切换，用户可以根据实际需求进行切换，并且传感器会保存已设置好的通信接口类型，下次使用时，不用再次设置。
  接口引脚说明如下：

  引脚	默认功能(UART)	复用功能 (I2C)	说明
  VCC	电源正	电源正	3.3~5.5V
  GND	电源地	电源地	GND
  C/T	UART-TX	I2C-SCL	传感器出厂默认为UART接口，若需要用I2C接口，参考模式切换。（端口模式为开漏，内部上拉6.2K电阻到VCC）
  D/R	UART-RX	I2C-SDA	传感器出厂默认为UART接口，若需要用I2C接口，参考模式切换。（端口模式为开漏，内部上拉6.2K电阻到VCC）
  EN	电源使能	电源使能	该引脚作为电源的使能脚，内部上拉，将EN拉低可以关断传感器电源，若不用此功能该引脚可以悬空不接。
  BUSY	RS485收发控制口	BUSY(开漏输出)	- 在UART模式下，该引脚可作为RS485收发控制口，外接一个RS485的驱动IC即可扩展得到RS485接口。 - 在IIC模式下，测距过程中BUSY端口将拉低，BUSY脚输出高表示空闲或上一次测距已经完成。该引脚可接到主机的中断口，在BUSY端口输出电平上升沿时可以及时的读取到传感器数据。
  TRIG	NC	TRIG	- UART接口下未使用 - I2C接口下作为外部端口测距触发引脚，上升沿触发。
  ECHO	NC	ECHO	- UART接口下未使用 - I2C接口下，当传感器测距功能被触发后，该脚引输出一个高脉宽，此脉宽代表超声波传播时间（单位：us）。

板载LED灯状态指示

• 在传感器上电后，LED灯闪烁1次，表示当前传感器为UART模式，此模式下每收到一次正确的主机命令时LED会闪烁1次。
• 在传感器上电后，LED灯闪烁2次，表示当前传感器为I2C模式，此模式下测距时LED闪烁1次。

UART与I2C模式切换

URM13传感器默认出厂设置为UART模式。 传感器可以在I2C、UART两种模式间通过上电前短接不同的引脚实现简单的模式切换：

• 在传感器上电前，将TRIG与ECHO引脚短接，上电后LED闪烁2次，表示传感器已切换为I2C模式。
• 在传感器上电前，将TRIG与BUSY引脚短接，上电后LED闪烁1次，表示传感器已切换为UART模式。

在模式切换成功后，用户即可断开对应引脚的短接，切换后的模式将被传感器记录保存，永久生效。

UART寄存器说明

UART接口下，传感器为Modbus从机，主机需要通过Modbus协议与传感器进行通信。

UART模式Arduino示例

准备

• 硬件
  • 1 x Arduino Leonardo控制板（因为打印输出信息需要占用一个串口，推荐使用两个串口以上的设备,示例中用的是Arduino Leonardo，由于Arduino Modbus协议会占用较大内存，所以建议使用Arduino Mega2560控制板）
  • 1 x USB数据线（USB数据线一端连接Arduino板USB口，另一端连接至电脑USB口）

• 软件
  • Arduino IDE， 点击下载Arduino IDE
  • 在IDE中打开Library Manager(Ctrl+Shift+I)，找到并安装ArduinoModbus和ArduinoRS485两个库

• 硬件接线示意图

基于Arduino Modbus库示例代码

/**************************************************************************************************************
     This code tests the range finder function of the URM13 ultrasonic sensor
     @ author : roker.wang@dfrobot.com
     @ data   : 21.08.2020
     @ version: 1.0
**************************************************************************************************************/
#include <ArduinoModbus.h>
#include <ArduinoRS485.h>

#define   SLAVE_ADDR                ((uint16_t)0x0D)

#define   TEMP_CPT_SEL_BIT          ((uint16_t)0x01 << 0)
#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)
#define   MEASURE_RANGE_BIT         ((uint16_t)0x01 << 4)

typedef enum {
  ePid,
  eVid,
  eAddr,
  eComBaudrate,
  eComParityStop,
  eDistance,
  eInternalTempreture,
  eExternTempreture,
  eControl,
  eNoise,
  eSensitivity
} 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;
}

int16_t  dist;float temp;
volatile uint16_t cr = 0;
void setup() {
  ModbusRTUClient.begin(19200);
  Serial.begin(9600);
  cr &= ~TEMP_CPT_SEL_BIT;//clear bit0, select internal temperature compensation
  //cr |= TEMP_CPT_SEL_BIT;//set bit0,select external temperature compensation
  cr &= ~TEMP_CPT_ENABLE_BIT;//clear bit1,enable temperature compensation
  //cr |= TEMP_CPT_ENABLE_BIT; //set bit1,disable temperature compensation
  cr |= MEASURE_MODE_BIT;//set bit2 , set to trigger mode
  //cr &= ~MEASURE_MODE_BIT;//clear bit2 , set to Automatic ranging mode
  cr &= ~MEASURE_RANGE_BIT;//clear bit4,long-range ranging mode
  //cr |= MEASURE_RANGE_BIT; //set bit4,short-range ranging mode
  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 100ms) is to wait for the completion of ranging
  dist = readData(SLAVE_ADDR, eDistance);//Read distance register, one LSB is 1cm
  delay(10);
  temp = (float)readData(SLAVE_ADDR, eInternalTempreture) / 10.0;//Read tempreture register, one LSB is 0.1 ℃
  Serial.print("dist = ");
  Serial.print(dist);
  Serial.print("cm---");

  Serial.print("temp = ");
  Serial.print(temp);
  Serial.println(" ℃");
}

基于Arduino串口发送命令示例代码

/**************************************************************************************************************
     This code tests the range finder function of the URM13 ultrasonic sensor
     @ author : roker.wang@dfrobot.com
     @ data   : 21.08.2020
     @ version: 1.0
**************************************************************************************************************/
#define   SLAVE_ADDR                ((uint16_t)0x0D)

#define   TEMP_CPT_SEL_BIT          ((uint16_t)0x01 << 0)
#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)
#define   MEASURE_RANGE_BIT         ((uint16_t)0x01 << 4)

#define   MB_OP_WRITE_SINGLE_HOLDING_REG  ((uint8_t)0x06)
#define   MB_OP_READ_HOLDING_REGS         ((uint8_t)0x03)

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

static const uint8_t aucCRCHi[] = {
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40
};

static const uint8_t aucCRCLo[] = {
  0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06, 0x07, 0xC7,
  0x05, 0xC5, 0xC4, 0x04, 0xCC, 0x0C, 0x0D, 0xCD, 0x0F, 0xCF, 0xCE, 0x0E,
  0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09, 0x08, 0xC8, 0xD8, 0x18, 0x19, 0xD9,
  0x1B, 0xDB, 0xDA, 0x1A, 0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC,
  0x14, 0xD4, 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2, 0x12, 0x13, 0xD3,
  0x11, 0xD1, 0xD0, 0x10, 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, 0xF2, 0x32,
  0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4, 0x3C, 0xFC, 0xFD, 0x3D,
  0xFF, 0x3F, 0x3E, 0xFE, 0xFA, 0x3A, 0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38,
  0x28, 0xE8, 0xE9, 0x29, 0xEB, 0x2B, 0x2A, 0xEA, 0xEE, 0x2E, 0x2F, 0xEF,
  0x2D, 0xED, 0xEC, 0x2C, 0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26,
  0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0, 0xA0, 0x60, 0x61, 0xA1,
  0x63, 0xA3, 0xA2, 0x62, 0x66, 0xA6, 0xA7, 0x67, 0xA5, 0x65, 0x64, 0xA4,
  0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F, 0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB,
  0x69, 0xA9, 0xA8, 0x68, 0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA,
  0xBE, 0x7E, 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C, 0xB4, 0x74, 0x75, 0xB5,
  0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, 0x70, 0xB0,
  0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92, 0x96, 0x56, 0x57, 0x97,
  0x55, 0x95, 0x94, 0x54, 0x9C, 0x5C, 0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E,
  0x5A, 0x9A, 0x9B, 0x5B, 0x99, 0x59, 0x58, 0x98, 0x88, 0x48, 0x49, 0x89,
  0x4B, 0x8B, 0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C,
  0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42, 0x43, 0x83,
  0x41, 0x81, 0x80, 0x40
};

static uint16_t mbCrcCalculated(uint8_t  * pCmd, uint8_t  usLen )
{
  uint8_t ucCRCHi = 0xFF;
  uint8_t ucCRCLo = 0xFF;
  int16_t iIndex;

  while ( usLen-- )
  {
    iIndex = ucCRCLo ^ *( pCmd++ );
    ucCRCLo = ( uint8_t )( ucCRCHi ^ aucCRCHi[iIndex] );
    ucCRCHi = aucCRCLo[iIndex];
  }
  return ( uint16_t )( (uint16_t)ucCRCHi << 8 | ucCRCLo );
}
/*
  @brief Read data from holding register of client

  @param addr ： Address of Client
  @param reg: Reg index
  @param regNum: The number of registers to read，The register is 16 bits wide
  @param pBuf:Points to the receive data buffer
*/
void readHoldingRegisters(uint16_t addr, eRegIndex_t regIndex, uint16_t regNum, uint8_t *pBuf)
{
  uint8_t pCmdBuf[8], i;
  uint16_t crc;

  pCmdBuf[0] = addr;
  pCmdBuf[1] = MB_OP_READ_HOLDING_REGS;
  pCmdBuf[2] = regIndex >> 8;
  pCmdBuf[3] = (uint8_t)regIndex;
  pCmdBuf[4] = regNum >> 8;
  pCmdBuf[5] = (uint8_t)regNum;

  crc = mbCrcCalculated(pCmdBuf, 6);
  pCmdBuf[6] = (uint8_t)crc;
  pCmdBuf[7] = crc >> 8;

  for (i = 0; i < 8; i++) {
    Serial1.write( pCmdBuf[i]);
  }
  delay(150);
  i = 0;
  while (Serial1.available()) {
    pBuf[i++] = (Serial1.read());
  }
}
/*
  @brief Write data to holding register of client

  @param addr ： Address of Client
  @param reg: Reg index
  @param data: The data to be sent
  @param pBuf:Points to the receive data buffer
*/
void writeSigleHoldingRegister(uint16_t addr, eRegIndex_t regIndex, uint16_t data, uint8_t *pBuf)
{
  uint8_t pCmdBuf[8], i;
  uint16_t crc;

  pCmdBuf[0] = addr;
  pCmdBuf[1] = MB_OP_WRITE_SINGLE_HOLDING_REG;
  pCmdBuf[2] = regIndex >> 8;
  pCmdBuf[3] = (uint8_t)regIndex;
  pCmdBuf[4] = data >> 8;
  pCmdBuf[5] = (uint8_t)data;

  crc = mbCrcCalculated(pCmdBuf, 6);
  pCmdBuf[6] = (uint8_t)crc;
  pCmdBuf[7] = crc >> 8;

  for (i = 0; i < 8; i++) {
    Serial1.write( pCmdBuf[i]);
  }
  delay(150);
  i = 0;
  while (Serial1.available()) {
    pBuf[i++] = (Serial1.read());
  }
}

uint8_t rxBuf[100];
int16_t  dist; float temp;

volatile uint16_t cr = 0;
void setup() {
  Serial1.begin(19200);
  Serial.begin(9600);
  cr &= ~TEMP_CPT_SEL_BIT;//clear bit0, select internal temperature compensation
  //cr |= TEMP_CPT_SEL_BIT;//set bit0,select external temperature compensation
  cr &= ~TEMP_CPT_ENABLE_BIT;//clear bit1,enable temperature compensation
  //cr |= TEMP_CPT_ENABLE_BIT; //set bit1,disable temperature compensation
  cr |= MEASURE_MODE_BIT;//set bit2 , set to trigger mode
  //cr &= ~MEASURE_MODE_BIT;//clear bit2 , set to Automatic ranging mode
  cr &= ~MEASURE_RANGE_BIT;//clear bit4,long-range ranging mode
  //cr |= MEASURE_RANGE_BIT; //set bit4,short-range ranging mode
  writeSigleHoldingRegister(SLAVE_ADDR, eControl, cr, rxBuf); //Writes the setting value to the control register
  delay(100);
}

void loop() {
  cr |= MEASURE_TRIG_BIT;//Set trig bit
  writeSigleHoldingRegister(SLAVE_ADDR, eControl, cr, rxBuf); //Write the value to the control register and trigger a ranging
  delay(300);//Delay of 300ms(minimum delay should be greater than 100ms) is to wait for the completion of ranging
  readHoldingRegisters(SLAVE_ADDR, eDistance, 1, rxBuf); //Read distance register, one LSB is 1cm
  dist = (int16_t)rxBuf[3] << 8 | rxBuf[4];
  delay(10);
  readHoldingRegisters(SLAVE_ADDR, eInternalTempreture, 1, rxBuf); //Read tempreture register
  temp = (float)((int16_t)rxBuf[3] << 8 | rxBuf[4]) / 10.0;// one LSB is 0.1 ℃
  Serial.print("dist = ");
  Serial.print(dist);
  Serial.print("cm---");

  Serial.print("temp = ");
  Serial.print(temp);
  Serial.println(" ℃");
}

I2C寄存器说明

I2C模式Arduino示例

###准备

• 硬件

  • 1 x Arduino Leonardo控制板
  • 1 x USB数据线（USB数据线一端连接Arduino板USB口，另一端连接至电脑USB口）

• 软件

  • Arduino IDE， 点击下载Arduino IDE

• 硬件接线示意图

示例代码

/*!
       Download this demo to test config to URM13, connect sensor through IIC interface
       Data will print on your serial monitor

       This example is the ultrasonic passive measurement distance and the temperature of the module.

       Copyright   [DFRobot](http://www.dfrobot.com), 2018
       Copyright   GNU Lesser General Public License

       version  V1.0
       date  21/08/2020
*/
#include <Wire.h>
typedef enum {
  eAddr = 0,
  ePid,
  eVid,
  eDistanceH ,
  eDistanceL,
  eInternalTempretureH,
  eInternalTempretureL,
  eExternalTempretureH,
  eExternalTempretureL,
  eConfig,
  eCmd,
  eNoise,
  eSensitivity,
  eRegNum
} regindexTypedef;

#define    MEASURE_RANGE_BIT        ((uint8_t)0x01 << 4)
#define    MEASURE_MODE_BIT         ((uint8_t)0x01 << 2)
#define    TEMP_CPT_ENABLE_BIT      ((uint8_t)0x01 << 1)
#define    TEMP_CPT_SEL_BIT         ((uint8_t)0x01 << 0)

#define    IIC_SLAVE_ADDR           ((uint8_t)0x12)
#define    isSensorBusy()           (digitalRead(busyPin))

int16_t    busyPin = 4;
/*
  @brief Write data to register of client

  @param addr ： Address of Client
  @param regIndex: Reg index
  @param pDataBuf: point to data buffer
  @param dataLen: data length
*/
void i2cWriteBytes(uint8_t addr, regindexTypedef regIndex , uint8_t *pDataBuf, uint8_t dataLen )
{
  Wire.beginTransmission(addr); // transmit to device
  Wire.write(regIndex);              // sends one byte
  for (uint8_t i = 0; i < dataLen; i++) {
    Wire.write(*pDataBuf);
    pDataBuf++;
  }
  Wire.endTransmission();    // stop transmitting
}
/*
  @brief Read data from register of client

  @param addr ： Address of Client
  @param regIndex: Reg index
  @param pDataBuf: point to data buffer
  @param dataLen: data length
*/
void i2cReadBytes(uint8_t addr, regindexTypedef regIndex , uint8_t *pDataBuf, uint8_t dataLen )
{
  unsigned char i = 0;
  Wire.beginTransmission(addr); // transmit to device #8
  Wire.write(regIndex);              // sends one byte
  Wire.endTransmission();    // stop transmitting
  Wire.requestFrom(addr, dataLen);
  while (Wire.available()) {  // slave may send less than requested
    pDataBuf[i] = Wire.read();
    i++;
  }
}

uint8_t cfg = 0, cmd = 0;
uint8_t rxBuf[100] = {0};
void setup() {
  Wire.begin(); // join i2c bus (address optional for master)
  Serial.begin(9600); // join i2c bus (address optional for master)
  pinMode(busyPin, INPUT);
  cfg &= ~MEASURE_RANGE_BIT;//clear bit4,long-range ranging mode
  //cfg |= MEASURE_RANGE_BIT;//set bit4,short-range ranging mode
  cfg |=  MEASURE_MODE_BIT;//Set bit2，i2c passive mode
  //cfg &= ~MEASURE_MODE_BIT;//clear bit2 , set to Automatic ranging mode
  cfg &= ~TEMP_CPT_ENABLE_BIT;//clear bit1,enable temperature compensation
  //cfg |= TEMP_CPT_ENABLE_BIT;//set bit1,disable temperature compensation
  cfg &= ~TEMP_CPT_SEL_BIT;//clear bit0,select internal temperature compensation
  //cfg |= TEMP_CPT_SEL_BIT;//set bit0,select external temperature compensation
  i2cWriteBytes(IIC_SLAVE_ADDR, eConfig , &cfg, 1 );
  delay(100);
}
void loop() {
  int16_t  dist, temp;
  cmd |= 0x01;//Set trig bit
  i2cWriteBytes(IIC_SLAVE_ADDR, eCmd , &cmd, 1 );//Write command register
  //You can replace the delay with these two lines of code
  //while(isSensorBusy()== HIGH);  //Wait for the sensor to start ranging
  //while(isSensorBusy()== LOW);   //Wait for sensor ranging to complete
  delay(100);//delay 100ms
  i2cReadBytes(IIC_SLAVE_ADDR, eDistanceH, rxBuf, 2 ); //Read distance register
  dist = ((uint16_t)rxBuf[0] << 8) + rxBuf[1];
  delay(10);
  i2cReadBytes(IIC_SLAVE_ADDR, eInternalTempretureH, rxBuf, 2 ); //Read the onboard temperature register
  temp = ((uint16_t)rxBuf[0] << 8) + rxBuf[1];

  Serial.print(dist, DEC);
  Serial.print("cm");
  Serial.print("------");

  Serial.print((float)temp / 10, 1);
  Serial.println("℃");
}

TRIG脉冲触发示例

准备

• 说明 使用此模式的驱动方式与SR04相同，在TRIG端口输入一个脉冲电平将触发传感器测距，测距完成后ECHO端口将输出一段脉冲电平，输出脉冲电平的宽度等于超声波的测量往返飞行时间。
  

  需要特别说明一下：
  1、TRIG模式下无法做量程切换，需要使用I2C接口配置或切换。
  2、TRIG模式下输出的脉冲宽度未做温度补偿。
  

  • 使用该模式前，请确认传感器为I2C模式，且为被动测距模式（I2C配置寄存器Bit2 = 1）

• 硬件

  • 1 x Arduino Leonardo控制板
  • 1 x USB数据线（USB数据线一端连接Arduino板USB口，另一端连接至电脑USB口）

• 软件

  • Arduino IDE， 点击下载Arduino IDE

• 硬件接线示意图

• 时序图

  

• 示例代码

/*!
       This example is the ultrasonic distance measurement of the module.

       Copyright   [DFRobot](http://www.dfrobot.com), 2020
       Copyright   GNU Lesser General Public License

       version  V1.0
       date  21/08/2020
*/
#define    VELOCITY_TEMP(temp)       ( ( 331.5 + 0.6 * (float)( temp ) ) * 100 / 1000000.0 ) // The ultrasonic velocity (cm/us) compensated by temperature

int16_t trigPin = 5;
int16_t echoPin = 6;
uint16_t distance;
uint32_t pulseWidthUs;
void setup() {
  Serial.begin(9600);
  pinMode(trigPin,OUTPUT);
  digitalWrite(trigPin,LOW);
  pinMode(echoPin,INPUT);
  delay(100);
}
void loop() {
  int16_t  dist, temp;
  digitalWrite(trigPin,HIGH);//Set the tirgPin High
  delayMicroseconds(50);     //Delay of 50 microseconds
  digitalWrite(trigPin,LOW); //Set the tirgPin Low

  pulseWidthUs = pulseIn(echoPin,HIGH);//Measure echo high level time, the output high level time represents the ultrasonic flight time (unit: us)
  distance = pulseWidthUs * VELOCITY_TEMP(33) / 2.0;//The distance can be calculated according to the flight time of ultrasonic wave,/
                                                    //and the ultrasonic sound speed can be compensated according to the actual ambient temperature
  Serial.print(distance, DEC);
  Serial.println("cm");
  delay(100);
}

常见问题

1、如有疑问，欢迎通过qq或者论坛联系我们！ 更多问题及有趣的应用，可以 访问论坛 进行查阅或发帖。

更多

[Link DFRobot商城购买链接] [11]: https://makelog.dfrobot.com.cn/wiki2/index/add/df_cn?subject=SKU_SEN0352_URM13_Ultrasonic_Sensor