@Todd_Fleming I would like to try GRBL-LPC on my smoothie board (C3D). Went through a great ordeal yesterday trying to get the settings right to engrave a raster image on wood. The stuttering with Smoothie is really my main reason for wanting to try this. I just want to make sure I go about it the right way and download the correct version from GitHub. I have PWM on pin 2.5. Do all the same guidelines apply for this GRBL version, such as M3 S0 in start gcode and M5 in end gcode in LW4 settings? Homing supported? I am thankful I stumbled upon this thread while searching throught this forum. Thank you for your work on this. Any other settings in config file I should verify before firing up the laser with this version?
Same guidelines as normal GRBL. Homing supported but only tested by a single person that I know of. Hard limits not supported.
@Todd_Fleming Could not connect to it. Do I have to use the version of LW3 at GRBL-Buffer? Thanks.
@Arion_McCartney My laser’s been packed away for a while, so I haven’t been able to test grbl-lpc with LW4. I just tested a board with nothing hooked up (no motors or lasers) with LW4 now; it was able to connect. Can you connect to it using a terminal (e.g. PuTTY)?
@Todd_Fleming I was not able to connect via PuTTY. I get no response. To be sure, I just downloaded the .bin and renamed it to firmware.bin, pace on SD card and power up the smoothie board. I tried LW3 and it did not work there either. The fact that I am getting nothing when connecting via PuTTY kind of leads me to believe I may have not loaded the firmware right or the board is not communicating with my computer?
@Arion_McCartney that’s the correct procedure. It looks like a driver problem or not using the right COM port, which is usually different from the COM port smoothie gets since it’s a different driver.
@Todd_Fleming I’ll try it again. Had the right com port but didn’t check driver. I’m sure that might be the issue now that I think of it. I’ll report back…
@Todd_Fleming Well , I tired. Had to disable windows driver signature verification to install the USBser.inf driver. That did not change anything. I reverted back to the driver Windows automatically assigned. Only thing I notice is that only after I place the firmware.bin on the sd card and insert it into the c3d board, I get all of the grbl settings in Putty terminal. That is the only time I ever get anything and the board does not respond to anything ( ex. $$). I have to place the firmware.bin back on the sd and power up again to get the settings sent again. No response even if I reset the board. At least I get something, right? Haha. Unless I am missing something, I might have to stick with Smoothie (as much as I really want to try GRBL). I loved GRBL on my diode laser. Worked perfectly.
Which Windows version are you on? Which of the 4 .bin files did you use?
Windows 10. Tried another Win 10 computer and same thing. That’s all I have. I tried all 4 of the bin files as a last resort “firmware-pwm_5khz_2_5.bin, firmware-pwm_5khz_2_4.bin, firmware-pwm_2khz_2_5.bin, firmware-pwm_2khz_2_4.bin” from here : https://github.com/gnea/grbl-LPC/releases
Very odd. I do all my development and testing on Windows 10. I just tried 3 of the 4 posted .bin files and they all connect correctly. When you write to the sdcard, do you eject before unplugging?
@Todd_Fleming Yes, I do eject before pulling the sd card out. When I put the card back into the computer to place a new firmware.bin file on it, it has the “firmware.cur” file is present on the card. Is your board a cohesion3d mini? Just want to make sure that my board vs other smoothie boards is in fact compatible or has been tested before.
Mine is a Smoothieboard 4x
@Todd_Fleming Maybe the difference in which smoothie board I am using is why I am having issues? That sucks 
Thanks for your time and helping me out.
@raykholo have you tried this firmware with one of your c3d boards?
@cprezzi sent me a new grbl-lpc build a few weeks back, I sent it on to @Ashley_M_Kirchner_No , he was unable to get it to flash on his Mini, Claudio could not get it to flash on his ReMix either. That’s as far as that got, I did not get to do more testing on boards here…
@raykholo ok thanks.
Hello Friends, i try to compile this grbl-lpc on my cloud9 space: https://ide.c9.io/xpix/grbl-lpc after some small changes and install the arm toolchain local ( i did this also for an MKS-SBASE at waiting time for the second tinyg) it was possible to compile this … after save this to sd and use with an c3d mini, the firmware answer with output of $$, but between the output text on serial console i saw an error:7 … after that grbl is crashed and i can’t connect again. The same firmware file works great on an MKS SBASE or Smoothiboard. Here my changes to compile this Firmware:
https://github.com/xpix/grbl-LPC/commit/c7b12ebc9d75412f58cb5d5dc70124203c836c10#diff-02ff30ca2a7eaf0ec9a1b2de22af4855
If you want to use this cloud9 space to compile ur own grbl-lpc, please send me a note and i can give u RW Access. To compile is easy:
cd && cd workspace && make clean && make
Error 7 is when it detects the flash config block isn’t initialized yet. Here’s how it should work: on first boot its config checksum fails, it issues error 7, and writes default values to the block. Next time it boots it should run without error 7. Flash is internal to the chip.
That’s very interesting.