Introduction
An ultrasonic sensor measures distance by calculating the time difference between sending a signal and receiving an echo from an object. It uses echolocation to measure distances, just like a bat.
The URM07 is an ultra low-power sensor. The effect range is up to 7.5m, and it has a wide range power supply of 3.0 - 5.5V. It is directly compatible with 3.3V or 5V devices such as Arduino, Raspberry Pi .etc. The average operating current is only 5mA and standby current is only 14uA.
According to the principle of ultrasound sensors, the accuracy of the distance value will be affected by the air temperature and wind direction, so using a DFRobot URM07 built-in temperature sensor, you can read the ambient temperature, and automatically calculate temperature compensation. The sensor uses an integrated ultrasonic probe with a detection angle of approximately 60° in a compact and lightweight unit. The unit uses a 2.54mm pitch 4Pin interface, using UART communication, compatible with most common microcontrollers.
URM07 UART ultrasonic distance sensors have undertaken rigorous road testing and optimization. We guarantee that this sensor has first-class response speed, ultra high stability, the highest sensitivity and ultra low power consumption. If you have harsh environmental requirements for your sensor performance in your design, the URM07 is definitely the best choice.
Features
- Streamlined design
- High Stability
- High Sensitivity
- Built-in temperature compensation
- Low Power Consumption
- Reverse polarity protection (short-term protection)
- Overvoltage Protection
- Convenient connection and Usage
Specification
- Operating Voltage: 3.0 ~ 5.5V DC
- I/O Operating Mode: Open Drain (OD), integrated pull-up resistor
- Effective Range: 20 ~ 750 cm
- Direction Angle: 60 °
- Standby Current: <14 uA (mainly by the power chip consumption, the core circuit consumption <1uA)
- Peak Current: <9 mA
- Average Current: <5 mA (measured under continuous measurement, for reference only)
- Distance Resolution: 1cm
- Distance Error: 1%
- Operating Temperature Range: -10 ~ 70 ℃
- Temperature Error: ± 1 ℃
- Operating Humidity Range: RH <75%
- Acoustic Frequency: 38 ~ 42KHz
- Boot Start Time: <20ms
- Measurement Period: <60ms
- Dimension: 27 * 27 mm/ 1.06 * 1.06 inches
- Weight: 4.2g.
Communication Protocol
- Factory parameters:
- Serial parameters: 19200 (bps) 8N1
- Factory address: 0x11
Communication Command Frame Format:
Header | Header 2 | Address | Data Length | Command | Data | Checksum |
---|---|---|---|---|---|---|
0x55 | 0xAA | 1 byte | 1 byte | 1 byte | Data 1~Data n | 1 byte |
Commands List:
Read distance | Read temperature | Set address | Set baud rate |
---|---|---|---|
0x02 | 0x03 | 0x55 | 0x08 |
Read the Measured Distance
The host sends a frame command to the ultrasonic module through the UART interface to trigger the module to start detecting, and then receives the distance value command returned by the module.
For example, the address of the ultrasonic module is 0x11, the host sends: 0x55 0xAA 0x11 0x00 0x02 0x12 [ 55 AA 11 00 02 12 ]
Description:
Frame header --------- 0x55
Frame header --------- 0xAA
Device address ----- 0x11
Data length ----- 0x00
Command --------- 0x02
Checksum ------- 0x12
The ultrasonic module returns data as: 0x55 0xAA 0x11 0x02 0x02 0x00 0xCA 0xDE
Description:
Frame header --------- 0x55
Frame header --------- 0xAA
Local address ----- 0x11
Data length ----- 0x02
Command --------- 0x02
Distance High ----- 0x00
Distance low ----- 0xCA (Distance value 0x00CA unit is centimeter, that is, decimal 202 cm)
Checksum ------- 0xDE
Read the Measured Temperature
The host reads the current temperature measured by the ultrasonic module via the UART interface.
For example, the ultrasonic module address is 0x11, the host sends: 0x55 0xAA 0x11 0x00 0x03 0x13 [ 55 AA 11 00 03 13 ]
Description:
Frame header --------- 0x55
Frame header --------- 0xAA
Device address ----- 0x11
Data length ----- 0x00
Command --------- 0x03
Checksum ------- 0x13
The ultrasonic module returns data as: 0x55 0xAA 0x11 0x02 0x03 0x00 0xFF 0x14
Description:
Frame header --------- 0x55
Frame header --------- 0xAA
Local address ----- 0x11
Data length ----- 0x02
Command --------- 0x03
Temperature high ----- 0x01
Temperature low ----- 0x13 (temperature value 0x0113, 27.5 degrees. Note: T = Returned value/10)
Checksum ------- 0x29
Set the Address of the Ultrasonic Module
The host sets the ultrasonic module address via the UART interface.
For example, set the ultrasonic module address 0x12, the host sends: 0x55 0xAA 0xAB 0x01 0x55 0x12 0x12 [ 55 AA AB 01 55 12 12 ]
Description:
Frame header --------- 0x55
Frame header --------- 0xAA
Device address ----- 0xAB (0xAB for the broadcast address, that is, all the common address of the module, you can use 0xAB instead of the device itself address if you are not sure the current Address)
Data length ----- 0x01
Command --------- 0x55
Set the address ----- 0x12 (need to set the device address 0x12)
Checksum ------- 0x12
Set the success of the ultrasonic module return command 0x55 0xAA 0x12 0x01 0x55 0xCC 0x33
Description:
Frame header --------- 0x55
Frame header --------- 0xAA
Device address ----- 0x12 (modified device address)
Data length ----- 0x01
Command --------- 0x55
Operation status ----- 0xCC (0xCC - operation completed 0xEE - operation failed)
Checksum ------- 0x33
Set the UART Communication Baud Rate
The host sets the ultrasonic module communication baud rate via the UART interface.
For example, if the address of the ultrasonic module is set to 0x11, the host sends: 0x55 0xAA 0x11 0x01 0x08 0x0B 0x24 //Set baudrate to 256000bps [ 55 AA 11 01 08 0B 24 ]
Description:
Frame header --------- 0x55
Frame header --------- 0xAA
Device address ----- 0x11
Data length ----- 0x01
Command --------- 0x08
Baud rate selection --- 0x0B
Checksum ------- 0x24
If the setting is successful, the ultrasonic module returns the command as: 0x55 0xAA 0x11 0x01 0x08 0xCC 0xE5
Description:
Frame header --------- 0x55
Frame header --------- 0xAA
Device address ----- 0x11
Data length ----- 0x01
Command --------- 0x08
Operation status ----- 0xCC (0xCC - operation completed 0xEE - operation failed)
Checksum ------- 0xE5
Baud rate Selection List:
1200bps | 2400bps | 4800bps | 9600bps | 14400bps | 19200bps | 28800bps | 38400bps | 57600bps | 115200bps | 128000bps | 256000bps |
---|---|---|---|---|---|---|---|---|---|---|---|
0x00 | 0x01 | 0x02 | 0x03 | 0x04 | 0x05 | 0x06 | 0x07 | 0x08 | 0x09 | 0x0A | 0x0B |
For example, when the device address is default 0x11, the baud rate setting command is as follows:
55 AA 11 01 08 00 19 //Set the baud rate 1200bps
55 AA 11 01 08 01 1A //Set the baud rate 2400bps
55 AA 11 01 08 02 1B //Set the baud rate 4800bps
55 AA 11 01 08 03 1C //Set the baud rate 9600bps
55 AA 11 01 08 04 1D //Set the baud rate 14400bps
55 AA 11 01 08 05 1E //Set the baud rate 19200bps
55 AA 11 01 08 06 1F //Set the baud rate 28800bps
55 AA 11 01 08 07 20 //Set the baud rate 38400bps
55 AA 11 01 08 08 21 //Set the baud rate 57600bps
55 AA 11 01 08 09 22 //Set the baud rate 115200bps
55 AA 11 01 08 0A 23 //Set the baud rate 128000bps
55 AA 11 01 08 0B 24 //Set the baud rate 256000bps
Arduino URM07 Ultrasonic Tutorial
Requirements
- Hardware
- DFRduino UNO (or similar) x 1
- URM07-UART Ultrasonic Sensor xn
- M-M/F-M/F-F Jumper wires
- Software
- Arduino IDE [https://www.arduino.cc/en/software| Click to Download Arduino IDE from Arduino®]
Here are some notes:
- With a single URM07 module, a generic device address 0xAB can be used instead if the device address is unknown.
- Before the power on the URM07 module is not started, set the TX port to high and lower the RX port, and maintaining more than 1s can enable the module parameters to revert to factory settings.
- After the factory reset, the module can not start normally to enter a normal communication state, the on-board LED light flash with 10Hz. The module starts normally when powered back on.
- After the module is started, the module on-board LED only lights up the indication during the process of receiving the data and processing, and the LED goes out when in the standby state.
Read Distance Value via Arduino (Single)
Description:
Default Address: 0x11; Default Baudrate: 19200 bps Leonardo GPIO Power Supply. (40mA) |
// # Author: Strictus.zhang@dfrobot.com
// # Date: 20.08.2016
// # Product Name: URM07-UART Ultrasonic Sensor
// # SKU: SEN0153
// # version number: 1.0
// # Code Description: 20-750cm distance measurement, the received data is not verified
// # Connection: Arduino LEonardo GPIO Power Supply
// # Pin VCC (URM07 V1.0) -> D3 (Arduino Leonardo)
// # Pin GND (URM07 V1.0) -> D2 (Arduino Leonardo)
// # Pin RX (URM07 V1.0) -> TX1/D1 (Arduino Leonardo)
// # Pin TX (URM07 V1.0) -> RX1/D0 (Arduino Leonardo)
#define header_H 0x55 //Header
#define header_L 0xAA //Header
#define device_Addr 0x11 //Address
#define data_Length 0x00 //Data length
#define get_Dis_CMD 0x02 //Command: Read Distance
#define checksum (header_H+header_L+device_Addr+data_Length+get_Dis_CMD) //Checksum
unsigned char i=0;
unsigned int Distance=0;
unsigned char Rx_DATA[8];
unsigned char CMD[6]={
header_H,header_L,device_Addr,data_Length,get_Dis_CMD,checksum}; //Distance command package
void setup() {
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
digitalWrite(3, HIGH); //Ultrasonic VCC
digitalWrite(2, LOW); //Ultrasonic GND
Serial1.begin(19200); //Serial1: Ultrasonic Sensor Communication Serial Port, Buadrate: 19200
Serial.begin(19200); //Serial: USB Serial Data output, baudrate: 19200
}
void loop() {
for(i=0;i<6;i++){
Serial1.write(CMD[i]);
}
delay(150); //Wait for the result
i=0;
while (Serial1.available()){ //Read the return data (Note: this demo is only for the reference, no data verification)
Rx_DATA[i++]=(Serial1.read());
}
Distance=((Rx_DATA[5]<<8)|Rx_DATA[6]); //Read the distance value
Serial.print(Distance); //print distance value
Serial.println("cm");
}
Read Temperature Value via Arduino (Single)
// # Author: Strictus.zhang@dfrobot.com
// # Date: 20.08.2016
// # Product Name: URM07-UART Ultrasonic Sensor
// # SKU: SEN0153
// # version number: 1.0
// # Code Description: Temperature measurement, the received data is not verified
// # Connection: Arduino LEonardo GPIO Power Supply
// # Pin VCC (URM07 V1.0) -> D3 (Arduino Leonardo)
// # Pin GND (URM07 V1.0) -> D2 (Arduino Leonardo)
// # Pin RX (URM07 V1.0) -> TX1/D1 (Arduino Leonardo)
// # Pin TX (URM07 V1.0) -> RX1/D0 (Arduino Leonardo)
#define header_H 0x55 //Header
#define header_L 0xAA //Header
#define device_Addr 0x11 //Address
#define data_Length 0x00 //Data length
#define get_Temp_CMD 0x03 //Command: Read Temperature
#define checksum (header_H+header_L+device_Addr+data_Length+get_Temp_CMD) //check sum
unsigned char i=0;
int temperature=0;
unsigned char Rx_DATA[8];
unsigned char CMD[6]={header_H,header_L,device_Addr,data_Length,get_Temp_CMD,checksum}; //Temperature Command package
void setup() {
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
digitalWrite(3, HIGH); // Ultrasonic Sensor VCC
digitalWrite(2, LOW); // Ultrasonic Sensor GND
Serial1.begin(19200); // Serial1: Ultrasonic Sensor Communication Serial Port, Baud rate: 19200
Serial.begin(19200); // Serial: USB Serial Monitor
}
void loop() {
for(i=0;i<6;i++){
Serial1.write(CMD[i]);
}
delay(50); //Wait Data Return
i=0;
while (Serial1.available()){ //Read returned Data (Note: Demo is just for Reference , no data verification)
Rx_DATA[i++]=(Serial1.read());
}
temperature=((Rx_DATA[5]<<8)|Rx_DATA[6]); //Read temperature Value (10 times)
Serial.print(temperature/10); //Print Temperature
Serial.print('.');
Serial.print(temperature%10);
Serial.println("C");
}
Read Distance Value via Arduino (Cascade)
Description:
Set different address first: 0x11; 0x22; 0x33; 0x44 Leonardo GPIO Power Supply. (40mA) Default Baudrate: 119200 bps |
// # Author: Strictus.zhang@dfrobot.com
// # Date: 20.08.2016
// # Product Name: URM07-UART Ultrasonic Sensor
// # SKU: SEN0153
// # version number: 1.0
// # Code Description: Cascade Connection: Temperature & Distance measurement, the received data is not verified
// # Connection: Arduino LEonardo GPIO Power Supply
// # Pin VCC (URM07 V1.0) -> D3 (Arduino Leonardo)
// # Pin GND (URM07 V1.0) -> D2 (Arduino Leonardo)
// # Pin RX (URM07 V1.0) -> TX1/D1 (Arduino Leonardo)
// # Pin TX (URM07 V1.0) -> RX1/D0 (Arduino Leonardo)
unsigned char i=0,j=0;
unsigned int Distance=0;
unsigned char Rx_DATA[8];
unsigned char CMD[4][6]={
{0x55,0xAA,0x11,0x00,0x02,0x12},
{0x55,0xAA,0x22,0x00,0x02,0x23},
{0x55,0xAA,0x33,0x00,0x02,0x34},
{0x55,0xAA,0x44,0x00,0x02,0x45},
}; //Distance Measurement Package
void setup() {
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
digitalWrite(3, HIGH); //Ultrasonic Sensor VCC
digitalWrite(2, LOW); //Ultrasonic Sensor GND
Serial1.begin(19200); //Serial1: Ultrasonice Sensors Serial Communication Port, baudrate: 19200
Serial.begin(19200); //Serial: USB Serial Monitor
}
void loop() {
for(j=0;j<4;j++)
{
for(i=0;i<6;i++){
Serial1.write(CMD[j][i]);
}
delay(150); //Wait returned result
i=0;
while (Serial1.available()){ //Read Returned Value (This demo is only for reference, no data verification)
Rx_DATA[i++]=(Serial1.read());
}
Distance=((Rx_DATA[5]<<8)|Rx_DATA[6]); //Read distance value
Serial.print("URM07-UART module["); //print distance
Serial.print(j);
Serial.print("]get_Dis= ");
Serial.print(Distance);
Serial.println("cm");
}
Serial.print("\r\n\r\n");
}
FAQ
Q&A | Some general Arduino Problems/FAQ/Tips |
---|---|
A | For any questions, advice or cool ideas to share, please visit the DFRobot Forum. |