I have in my hand a distance laser sensor with high precision and speed. It is used in industrial environments for object positioning or detection applications. According to technical documents, I found it can communicate with other devices via RS485. I spent the weekend to learn it and find ways to communicate with cheap CPU – Arduino. And finally, I succeeded in reading data from it and displaying the distance value on the led screen.
And I’m willing to share this test with you. Let’s start with the video below:
Step 1: B.O.M
Main components include:
- Arduino Uno R3.
- Arduino Mega 2560. (Option to check the RS485 communication because it has multiple serial ports. We can use Arduino Mega 2560 to print the value on Arduino IDE for program debugging).
- Module RS-485. It is very cheap, about $0.4 on AliExpress.
- LOL Shield Matrix. For LoLShiled, I did it by myself at home. You can refer to PCB design at: https://github.com/jprodgers/LoLshield & make one for yourself.
- Distance Laser Sensor.
- 40 pin male header (4 pcs).
- 40 pin female header (4 pcs).
- Double Side Prototype PCB.
- Ribbon Cable.
- Power Supply 5VDC and 24VDC. For me, I used a power supply PS 307 from Siemens.
Step 2: CIRCUIT DIAGRAM AND ASSEMBLY
The circuit schematic is shown on picture above.
My idea is to read distance data and display this value on LoLShield. To do this, I had to turn the RS-485 module into a Shield to plug it on the Arduino and then Lolshield matrix will be plugged on the top.
- Soldering RS-485 Shield:
RS-485 Shield after soldering with male header at bottom and female header on the top.
Step 3: DISTANCE LASER SENSOR – TECHNICAL SPEC
The laser distance sensors S80 SERIES (DATALOGIC) with time of flight measurement are suitable for long distance measurements offering constant performances on the entire range. In my case, this S80-Y0 sensors function as proximity on respectively a 0.3 – 4 m distance, or from 0.3 to 7 m with scalable range.
About RS485 serial interface:
The serial communication parameters are: 9600 baud, no parity, 8 data bits, 1 stop bit. It is matching with serial interface “SERIAL_8N1” in “HardwareSerial” Arduino’s library.
The SYNC input is used to determine the communication direction, and in particular if low (active) direction Sensor->Arduino, if high (passive) Arduino->Sensor. You can review the diagram in Step 2, the SYNC signal is connected to 0V/GND to active receive mode.