laser measuerment 'module'

Mate picked up one of these fo 20 recently.

Its accurate to 2mm.

Let the hacking begin


Any updates?

I'm also need connect laser distance meter to Arduino and get the distance value in my program code.

No sorry.

There was a module for arduino a couple of years ago but they seem to be permanently out of stock.

Lidar3 is out now at Sparkfun.

thanks, but $150 it's too much for my project..

I hope that I can connect Arduino with BOSH PLR 15 which costs about $40. But I need to know to connect it and how to control from program code.

I tried but like this guy.

The command codes are all proprietry and guesswork does not cut it.

I bought PLR 15 and going to solder wires to debug pins.
I need to know how to connect it to computer for checking commands codes.

I don’t understand this:
“I think, it is a command to pin 7 needed, to start the communication. Caution RX and TX are working together on the same debug pin no. 7.”

is it possible to connect it via FT232RL FTDI USB to TTL Serial Adapter like this:


I’m using it for connect Arduino Mini to my laptop and send/receive commands to COM port.

Please advice.

I am unfamiliar with the device you are using but the rs232 protocol uses both negative and positive voltages , this would be unsuitable. Check the device no on the chip and look it up.


I purchaced something similar to this.

Same chip.

Turned it over and there was a level converter on the other side. >:( One i got was advertised as a TTL level


But how did you connect your PLR15 to COM port?
You said that

Send to debug pin 7 with 9600 baud, 8 data, 1 stop, no parity a command higher or equal than C0h. The response is always the same after 60ms with 3 bytes: 01h 00h FAh. And the laser go never in the power on state. Only the LCD backlight is on. Anyone have a good idea for the communication?

Or it is not you?

I would also connect it and send some commands.
But I need first connect it, but don’t know how.

No sorry not me.

I origonally used a data analyser but lost access to that a year or so back.

Thank you anyway..

It is still a work in progress depending upon what santa brings me. :)

The github link shows a connection diagram for the other unit though.

Another possibility. I tried the prigonal 390B but was shipped the 390B+ instead which has the hacking port removed. I would not be surprised if other vendors have likewise made modifications to make hacking harder.

Yep, I've checked this firstly and didn't find 390B for good price. Now it costs about $80 at the same time pric for 390B+ is a half less.

I disassembled my PLR15 and checking how to connect it to FTDI adapter.. So far no good results (

Those that hacked the 390 got lucky i think. If that is a debug port it will not necessarily give useful information and it is possible to brick the unit.

Best to look for I2C or similar interface between the display and processor. IF it exists.

If you could align two lasers parallel to put 2 dots of light on a target, the apparent distance between those 2 spots could give you a good idea of range.

But if the light reflected made an interference pattern, the distance between the nodes might tell more.

What can I say? Back in 73 when we did the double-slit using lightbulb light through red filter for source light we knew the distance and calculated the wavelength by holding a meter stick and judging the distance of the red nodes that appeared in front of us. And it worked. So knowing the wavelength we could get distance at probably twice as far or more.

GoForSmoke: But if the light reflected made an interference pattern,

The store ones use a phase measurement similar to this i think ,unlike the lidar modules which measure time of flight.

Light moves 300 meters per microsecond. With gigahertz timing......

I've used old radars (mid-70's) that sent a pulse out and on return it would blip the scope trace.

I used to do time domain reflectometery to find cable faults , similar principal.