Manual
LW20 / SF20 LiDAR sensor  
Product manual 
6. How to communicate with the LW20 using a terminal emulator 
To use a terminal emulation application to setup and test the LW20 you will need to connect the serial port of the LW20 to the USB 
port  on  a  PC.  This  is  done  using  a  serial-to-usb  converter  such  as  the  TTL-232R-3V3-WE  converter  cable  from  FTDI  (http://
www.ftdichip.com/Products/Cables/USBTTLSerial.htm). This converter provides both the signals and power supply to the LW20. 
Figure 10 :: Connection to a USB converter cable 
Once the converter is wired up to the LW20, prepare the Terminal application on the PC as follows: 
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 Download and instal the Terminal application from the LightWare website 
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 Other terminal emulation programs with the correct communication parameters will also work 
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 Open the Terminal application 
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 Select the “Laser” icon 
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 Set the baud rate to 115200 
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 You can tick the “Remember settings” box if you intend to use this configuration again 
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 Apply the change to close the dialog window 
Figure 11 :: Setting the baud rate for LW20 communications 
To es ta b lis h  co mm u nic at io n  b etw ee n  th e  LW2 0  an d  t he  Term in al  a pp l ica ti on : 
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Plug the LW20 converter into a USB port on the PC 
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Click the “Connect” icon - a notice of the connection and its associated USB port number should become visible on the toolbar 
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Press the <up arrow> to engage serial communication mode. The LW20 will reply with a product code. 
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The LW20 is now running in machine-to-machine mode and will respond to the set of machine commands 
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Press the <?> key followed by <CR>. The LW20 will reply with the product code, hardware revision and software revision 
In this mode, the LW20 will respond to the command set normally used by a controller to communicate using either the serial or I2C 
ports. The “?” command mentioned  above  is  the  command  used  to  identify  the  LW20.  The  full  command listing can be found in 
Appendix C. 
LW20 / SF20  LiDAR - Product manual - Revision 9 |    of    | © LightWare Optoelectronics (Pty) Ltd, 2018 | www.lightware.co.za 11 28










