2.2 Initial Configuration GRBL LPC 1.1

GRBL-LPC 1.1

We have ported the ingenious GRBL 1.1 to LPC1769 boards (like Smoothieboard, Cohesion3D, Azteeg X5, MKS SBASE). Grbl has an efficient streaming protocol with additional realtime commands which makes it ideal for near realtime needs at very high performance. This is especially important for CNC Milling (where you can pause/stop immediately and not have to wait until the queue is empty) or Laser Raser Engraving (very high speed).

Installing grbl-LPC

Written by Claudio Prezzi	
Last Updated: 11 July 2017 

For an easy install of grbl-LPC, we have prepared several precompiled firmware versions. Please check https://github.com/cprezzi/grbl-LPC/releases for the latest versions available.

• Rename the downloaded firmware file to firmware.bin
• Save the firmware.bin to the SD card
• Reboot your board
• Connect the board from LaserWeb4
• If you get the message No supported firmware detected, you can make a file called .env (nothing in front of the dot) with a text editor in the installation folder and enter RESET_ON_CONNECT=1 in the text. Then restart LW4.
• Get actual settings by sending $$ with the console (bottom right of LW window)
• Configure all $ settings according to your needs (check https://github.com/gnea/grbl/wiki for configuration details)
• Have fun!

Configure GRBL settings

Written by Claudio Prezzi	
Last Updated: 19 June 2017 

To configure your GRBL based board, you need to be connected with LaserWeb or a terminal program. In LaserWeb, you can send commands manually with the command line on the bottom right of the screen. After typing in the command, you have to press ENTER to send it to GRBL.

Send $$ to get a list of the actual configuration. To set a param you have to send $num=val (ex. $10=0).

Make sure the following params are set (matching your machine):

$10=0      ;send work coordinates in statusReport (needed for LW4!)
$3=3       ;invert X and Y stepper direction
$5=1       ;endstopps are NC (normaly closed)
$22=1      ;activate homing
$23=1      ;homing in X- and Y+ direction
$30=1000   ;max. S-value for Laser-PWM
$31=0      ;min. S-value
$32=1      ;Laser Mode on
$33=5000   ;PWM frequency 5000 Hz (lower = better grayscale, higher = better cut)
$100=160   ;steps/mm in X, depending on your pulleys and microsteps
$101=160   ;steps/mm in Y, depending on your pulleys and microsteps
$102=160   ;steps/mm in Z, depending on your pulleys and microsteps
$110=24000 ;max. rate mm/min in X, depending on your system
$111=24000 ;max. rate mm/min in Y, depending on your system
$112=24000 ;max. rate mm/min in Z, depending on your system
$120=2500  ;acceleration mm/s^2 in X, depending on your system
$121=2500  ;acceleration mm/s^2 in Y, depending on your system
$122=2500  ;acceleration mm/s^2 in Z, depending on your system
$130=300   ;max. travel mm in X, depending on your system
$131=200   ;max. travel mm in Y, depending on your system
$132=50    ;max. travel mm in Z, depending on your system
$140=0.4   ;X stepper current 0.4A
$141=0.6   ;Y stepper current 0.6A
$142=0.0   ;Z stepper current 0.0A

$$         ;to check the actual settings

These settings are an example of a K40 system. See https://github.com/gnea/grbl/blob/master/doc/markdown/settings.md for more details.