Grbl on RAMBo w/ Dual Endstops!

Software / Firmware GRBL
21

I apologize if this was addressed elsewhere but what are the pins/connections for spindle control (e.g., spindle I/O, spindle speed control) on the Rambo board for use with your GRBL branch?

Thanks!

1 Like
22

Cannot wait to try this out! I will let you know.

I have Rambo with dual endstops, if it works as easily as you say, Ill send you a pizza or something!

23

Is there a way to wire a physical button (feed hold, cycle start), as you would on a grbl aurdrino board?

24

@johnboiles I'm wiringthe endstops on my lowrider. I'm planning to have endstops on both Y axis (like on the mpcnc), on the X axis (X-min) but also on both Z axis (to go to the higher position of the machine and make it leveled). I also want to use an Z probe. Are the Z-min and Z-max already configured to let me do this or is there something to change the Firmware ? I already changed the homing cycles relatively to the Axis names (not the same for the lowrider than for the MPCNC)

 

thank you for your help, and if anybody have a solution it’s always welcome

 

25

Hi everyone,

again 'im making my path into this !! it’s fun !!

is there any risk that you had make mistakes in the attribution of the RAMBO’s pins into the “CPU_MAP.H” ? I found this

cpu_map.h

line 480

#define MIN_LIMIT_BIT_0 6 // X Limit Min - D12 / PB6
#define MIN_LIMIT_BIT_1 5 // Y Limit Min - D11 / PB5
#define MIN_LIMIT_BIT_2 2 // PH4


but when I check on the RAMBO schematic prints it seems to me that it’s not the same … I also found here when @johnboiles add the cpu map of the RAMBO, what seems to be the corrects pins but it is no more in the download files.

thank you for your help

Schematic-Prints_RAMBo_1.4a.pdf (3.26 MB)

26

I am having trouble with the GRBL dual endstop setup.

I have an SKR v1.4 board with the ‘GRBL on Rambo’ firmware. This is attached to a raspberry pi4 running cnc.js.

When I connect through USB, I can send commands and receive msg from the machine just fine. So GRBL and cnc.js are talking. When the initial startup is complete the steppers do not even power on. I can slide the gantries around. If I try to jog I get an error 2 soft limits.

However, when I flash Marlin onto the SKR board and select Marlin in CNC.js everything works fine and I’ve drawn a Crown no problems. So I’m assuming it’s a setting in GRBL somewhere. I disabled Homing Init lock and the safety door lock as well.

Which setting should I look into and where are the stepper drivers defined?

Thanks

27

I think grbl disables the motors like right away after you’re not moving them. You can set $1 to 255:

2 Likes
28

Thanks for the suggestion. Sorry for the delay, but I just got back to trying the $1=255 and still nothing. No power ever goes to the steppers. GRBL reports back the change in position just fine. Are the same pins enabled in both GRBL and Marlin?

29

You’re using code from the mpcnc-rambo-support branch in my repo right? https://github.com/johnboiles/grbl-Mega-5X/tree/mpcnc-rambo-support

You have an original RAMBo 1.4?

1 Like
30

Yes, but I’ll re-upload your original to the board just in case. I WAS changing quite a few variables there for a while.

Thanks

31

Ok, so all I changed was $1=255 and still nothing fom steppers. My switches have no affect on the Pn:XYXH readout when I open them from NC.

It’s seems like the pin assignment for the steppers is off??

Thanks

sorry about the blank posts, Didn’t realize the posts go on to a second page, didn’t think my post was going through.

32

 

 

33

Still nothing from the steppers. I’ve only changed $1=255. When I ‘?’ the output Pn: XYXH does not change when I hold any of my normally closed limit switches

34

John,

I just completed the build of 48 x 36 MPCNC w/ Dual end stops and it is working OK for CNC but lacks some features for the operation of a JTech 7 watt+ laser (Latest version). Will your port of Grbl work with LightBurn and or support Laser Functionality? I am game for being a tester on your Distro. I am setting up a Raspberry pi 4b now and will be testing your distro soon. Thanks for all the Hard work on this! oh, forgot to also mention that I have a SuperPID controlling a DW660 which works awesome. Any help connecting that to the correct pins would be great. I am currently running it in manual mode. I have LEDs connected to FAN0 and my JTech Laser on FAN1 I could remap FAN2 to Pin 44 or some other 5v PWM assignment for the SuperPID. Then just need a pin for the On/Off spindle function of the SuperPID. Thanks again!

1 Like
35

I don’t have any of that hardware so your on your own! But if it’s supported in grbl we should be able to make it work.

Check out the pins in cpu_map.h. If you know what GPIO you want to connect things to I can probably help you turn it into the ATMega port/pin registers used.

36

John,

I installed the firmware in my RAMBo and got a Pi 4b going with octopi and CNCjs. With light burn connected I can move the X and Y axis and home the machine, run a “$$” to get config parameters etc. but the Z axis will not move? on the CNCjs I can use the home button on the top of the screen but all else does not work at all and the z axis is non functional as well. any idea how to kick start this thing. once I have it moving correctly I’ll tackle the Laser mode functionality and go from there. on the CNCjs I am getting an Error 9. Thanks for your time!

37

Hi. I have been trying to switch from Marlin over to Grbl and found your thread and GitHub repository. Thanks for all the work you and others have put into getting this working.

I need a bit of help. I am trying to compile and upload the mpcnc-ramps-update-nc-endstops branch. I keep getting an error. It looks like this:

Arduino: 1.8.6 (Windows 10), Board: “Arduino/Genuino Mega or Mega 2560, ATmega2560 (Mega 2560)”

C:\Users\Customer\AppData\Local\Temp\ccplIBM7.ltrans1.ltrans.o: In function `main’:

:(.text.startup+0x9e4): undefined reference to `set_current’

collect2.exe: error: ld returned 1 exit status

exit status 1
Error compiling for board Arduino/Genuino Mega or Mega 2560.

Can anyone help me figure out what I am doing wrong? Thanks.

1 Like
38

Not sure why your z axis doesn’t work. We’re you able to figure it out?

39

Are you using the Arduino IDE to compile GRBL? I don’t think GRBL is made for Arduino. There’s a Makefile in the repo for building the firmware. It might need to be modified to run on Windows I’m not sure.

Edit: I am wrong. Grbl doesn’t use the Arduino framework but it absolutely can be compiled using the Arduino IDE

40

I am using Arduino IDE. That is what the main GRBL github page walks you through to flash a board. I didn’t know there was another way. Can you point me in the right direction of where to find information on how to get this flashed to my board? Thanks.

1 Like