LW20/C Laser altimeter

It is set to 102 (0x66) so it seems fine to me.

Hi,

Same problem here on a just received unit. Upgraded to the 1.4.1fw (latest from the upgrade thingy) and activated compatibility mode, it overloads the pixhawk’s power supply (which can clearly be seen as the red led on the unit blinks a few time, then shuts off
 so as the GPS’s led)
I do use the "select interface "mode though and it still does it which is not the exact same behaviout as @Anubis from what i can see
 I need to try the ferrite option
 but maybe it would be great to have this built in in next runs?

thanks

Yeah, after further testing, I found that Select Interface mode still causes the power issue sometimes. Also, I found that the ferrite bead does not work for all lidars. Right now, the best way to get around this is by supplying the lidar with a separate 5V power source from a UBEC or something.

Hello, I’m using a LW20/Serial SN S20-00321 MFD 2017/06 on arduplane 3.9.2
Everything is working correctly on NuttX but not working on Chibios with these same parameters:
RNGFND_ADDR,0
RNGFND_FUNCTION,0
RNGFND_GNDCLEAR,5
RNGFND_LANDING,1
RNGFND_MAX_CM,9500
RNGFND_MIN_CM,5
RNGFND_OFFSET,0
RNGFND_ORIENT,25
RNGFND_PIN,-1
RNGFND_POS_X,0
RNGFND_POS_Y,0
RNGFND_POS_Z,0
RNGFND_PWRRNG,0
RNGFND_RMETRIC,1
RNGFND_SCALING,1
RNGFND_SETTLE,0
RNGFND_STOP_PIN,1
RNGFND_TYPE,8
on Terminal, I have these data on firmware:
image
Do you have the same issue on Chibios ?
Thanks

Hello, i have an SF20/C (same as yours but decased version) working well under ChibiOS. I didn’t do anything to it, just updated to 3.6 RC12 on ChibiOS and it still works fine.

Mine has same version 2.0 firmware as yours and mine doesn’t connect to the upgrader either but i think it is not necessary to update a 2.0 firmware.

I am using it on I2C buss.

regards,

Corrado

Received a brand new SF20/C from lightware in substitution of my old SF20/c that was not working for anything higher than 50 meters.

New one just plain doesn’t work in I2C. I am sure everything is correctly setuop because old one works when connected, while new one reads zero, no matter what.
Set it up to start in I2C mode but to no avail. I wrote to them to see if there is something i can do, in case it still doesn’t work i guess i’ll send it back to them and keep my semi faulty one that at least works up to 50 meters.

Really a struggle with these lidars lately.

Which firmware version are you using? Make sure you’re using the latest one; they’ve recently improved the power issue and added I2C compatibility for Pixhawk. https://support.lightware.co.za/

I updated with an upgrader i had from a month ago and i see now there are newer ones, i now closed myself out because i set it as I2C. I guess i have no solution here.

Corrado

The newer upgraders can read the device in I2C mode if you use a Devantech USB-ISS adapter (I had to get one for the same reason).

I also just received a SF20/C and am having problems.

I Initially hooked it up to Telemetry 4 (pixhack v3). Configured per Ardupilot docs:

Setup Guide

and LiteWare Github insturctions posted earlier in this thread:

LightWare Setup Guide

Triple checked parameters, but I get no reading on the stats tab under sonarrange.

Switched TX/RX just to make sure and still no joy.

Wired up to a FTDI 3V3 USB dongle I have and ran the terminal software (V1.3.1), it did not ask me to update the FW and I don’t see where to manually check. I also can choose a COM port and didn’t see a “manage” tab, as the guide suggests, where I could set it to start in serial mode only. However, I can click the connect tab and the device seems to work very well and accurately inside the GUI. I can change and it responds.

I did Find one drop menu in the setting tab on the initial window that contained “serial” and 2 types of I2C protocols as options, but it was set to serial, so i just left it.

I closed out, re-soldered to my serial port connector and booted FC and still have no reading.

I have not tried using a separate power source yet and I don’t want to set ti to I2C because I don’t have the adapter if I lock it out and I don’t want to use the I2C bus anyway.

Any info on what I may be missing in the configurator, or any other information would be greatly appreciated.

You can update the 20/c’s firmware and change settings using the upgraders found here: https://support.lightware.co.za/

If you plan on using serial communication, you will probably have to set it to force serial mode.

They haven’t added these capabilities to the LW terminal software, which hasn’t been updated since the 20/C was released.

Know where i can get one of those? Looked up on amazon but couldn’t find one.

Corrado

I got mine from Acroname. If you google devantech usb-iss, there’s other retailers, including outside the US.

Ok thanks, i’ll get one.

Corrado

Rick,

Thanks for the reply. I have already connected to the Terminal (v1.3.1) and everything works perfectly in there, but I can not find the settings per the instructions listed on LiteWares Github. The link you supplied does not even contain the current version of the Terminal software? Are there two different programs for setup vs. firmware update?

Yes, it is 2 different programs, have to use upgrader to upgrade firmware.

Corrado

I see it now, oops. I re-soldered to FTDI and updated FW then configured to start up in serial mode (can you tell me about “serial banner”?)

Re-crimped JST-GH pins, plugged into Telemetry 4 and still doesn’t work.

Thanks for the help so far, I’ll hook it up to the FTDI again and take some screen shots tomorrow.

Thanks for the help, I’ve got it more or less figured out.

After rechecking all the parameters, upgrading to v1.5 FW and trying multiple serial ports on the FC

I upgraded to plane 3.9.2 ( I was on currently using 3.8.5 ) and it just works


edit: I should add for clarity that the 3.8.5 we were running was slightly modified to communicate with our ECU. I will upload an untouched 3.8.5 and see if the LightWare sensor continues to work.

Got the devantech today.

Doesn’t connect to the lightware. Did you do anything special to it?

Corrado

No, the upgrader will detect the devantech device and it just worked out of the box for me. Check your wiring and also the voltage selection jumper. It should be on the right-hand set of pins, if you are looking at it with the USB port facing up.

That said, I actually have a couple lidars that won’t communicate at all, so maybe you’re in the same boat. I don’t see a way to specify the I2C address when connecting with the upgrader or LW terminal, so maybe they’re set to a different address.