Ultrasonic Distance Measurement NRF905 Wireless Transmission

ICStation Team introduces you this ultrasonic distance measurement NRF905 wireless transmission system with ICStation UNO and Mega 2560 compatible with Arduino. The working voltage is DC5V. It uses ultrasonic frequencies to measure distance and realizes wireless transmission with NRF905. The minimum accuracy of this design is one centimeter. The measuring effect is best between 3 and 100 centimeter. It can be used in the areas with no high demand of accuracy, such as the obstacle avoidance of robot and a distance detection alarm when reversing a car.

Functions

1. When start up, the hardware initializes. The ranging module displays the prompt characters. After the initialization of the ultrasonic module finishes, it begins to display the measuring distance and starts the wireless transmission.

2. When the transmitting module is active, you will see the sending end of the development board flash, at the same time, the value displayed on the LCD1602 refreshes continually.

3. In the receiving end, when it receives the data successfully, the LED on the development board flashes and data is sent to the upper computer to display.

4. When change the distance between the object under test and ranging module, observe the data displayed on the LCD1602 in the sending end and the upper computer in the receiving end. When increasing and decreasing the measuring distance, the displayed data changes correspondingly and the response accuracy is 1 centimeter.

Code for your reference

RX part:

http://www.icstation.com/newsletter/eMarketing/nRF905_wireless_transmission.txt

TX part:

http://www.icstation.com/newsletter/eMarketing/nRF905_TX4_17.txt

Step 1: Components list

1. ICStation ATMEGA328 UNO V3.0 R3 Board Compatible Arduino UNO R3
2. ICStation ATMEGA2560 Mega2560 R3 Board Compatible Arduino
3. NRF905 Wireless Module
4. For Arduino Ultrasonic Module HC-SR04 Distance Transducer Sensor
5. 1602A HD44780 Character LCD Display Module LCM Blue Backlight
6. 10pcs Dupont 20cm Color Cable Line 1p-1p Pin Connector

Step 2: The hardware schematic diagram of receiving end

Step 3: The hardware of sending end

Step 4: Connect NRF905 module to the ICStation UNO

Define the NRF905 module and ICStation UNO as following and connect the sending end and receiving end:

• TXEN = 5
  
• TRX_CE = 6
  
• PWR = A0
  
• CSN = 4
  
• AM = 7
  
• DR = 3
  
• CD = 2
  
• MOSI = 11
  
• MISO = 12
  
• SCK = 13
  

Step 5: Connect the ultrasonic ranging module to the ICStation UNO

The definition of the pins of HC-SR04 module as the picture shows.

Define other functional pins as following:

• TrigPin = 8
  
• EchoPin = 9
  

Step 6: Connect the LCD 1602 to the ICStation UNO

Define other functional pins as following:

• RS = A1
  
• E = A2
  
• D4 = A3
  
• D5 = A4
  
• D6 = A5
  
• D7 = 10
  

Step 7: The whole effect of sending end after connection

Step 8: The whole effect of receiving end

Step 9: Video to show the effect