Has anyone tried the Arduino Nano for control?

Anyone? Anyone?

The reason I'm asking is that I found these on Amazon:



This would be the cat's *** for controller for cnc machines. The Nano seems to use the same processor and has actually a couple more I/O's. This would be a really compact solution.

 

So the programming interface and windows drivers are the same? And GRBL runs fine on them?

I use Xloader to load GRBl into an Uno with a screw terminal shield, not usually the Arduino interface.

And, I use external stepper drivers like these to control the motors, I can get up to 3A from them:


I just use the output pins from the Arduino to drive the inputs to these drivers, which are all optoisolated.

 

Cool. Thanks so much, Kyo.

 

hey Kyo, when you use a Nano, are the pins for the limit switches different than with the Uno?

I'm having a weird problem where the homing doesn't work properly. All the axes and control works properly, but when I do a Home, the z moves up normally, but then whichever of X or Y axis gets to the home switch first stops the homing cycle. It never completes on the last axis. Does not give homing error.

I am using GRBL 0.9j, and the Uno shows pins 9,10, and 12 for the x,y,z limits, but the diagram for the Nano shows 9,10,11. Which is it?

MG

 

Yes, only homing is enabled, hard limits are disabled. What do you mean if PWM is enabled? I was not aware you could change it. I don't recall seeing any setting for PWM in the GRBL settings window. I thought only GRBL V0.8 and lower used your bottom pinout, V0.9 used the top pinout...

The machine worked previously with an Uno, now I have tried 2 different Nanos and have the same problem with both. Homing switches are prox sensor types. I am going to go back to the Uno and see if it works again.

I also noted that the 5V seems pretty low when using the Nano. It's only about 4.6V. Wondering if the LED's on the optoisolators for the stepper drivers are drawing too much current and pulling the supply voltage down. Seems to function correctly, though.

This is the diagram I found for the Nano:



Note that it shows this pinout even for GRBL V0.9, which has pins 11 and 12 swapped on the Uno... But, it is suspect because it does not show PWM for the spindle pins...

Thanks Kyo.

PS: How Can You Live Without Homing?????

 

Yeah, that's actually the way I had it wired up (0.9j diagram). I just wasn't sure because of the diagram I had showing good for 0.9 versions.

In any case the Z limit works fine, its only x and y that do not work properly. As far as I can see, the sensors work, the board works, GRBL Panel has full functionality, they just don't work as a team...

 

Thanks Northernboy, I'll give that a try. What part of the Great White North are you in?

I did find the issue with low 5V on the Nano, it has a diode between the USB 5v and the board 5v, hence the voltage drop. It was not caused by too much load on the board. I would have to use a separate external 5V to fix this.

I want to do a "motherboard" for the Nano and incorporate the low pass filters for all the inputs, 12V (for prox limit sensors) and 5V supplies, and connectors for the stepper drivers to cut wiring time. Perhaps a relay for coolant and an output for spindle control SSR as well.

MG

 

Northernboy, That worked like a charm. A 0.1uF cap on each input line fixed the problem completely.

Thanks, Mang!

 

Cool, I'm in Calgary.

I just bought one of these aspirator type coolant misters off Ebay. It uses air pressure to suck up lube so you don't need a pump. Any chance you could send me your Arduino schematic and code for the mister controller? Or better yet, post it up on the Forum...

Does the SSR work properly with the PWM output from the Arduino? I assume you are using GRBL 0.9. I suppose you could just generate the g-code with router speed always set to maximum...

MG

 

OOOooo, fancy, LCD display and everything...

Right, but you are using the PWM output on the Arduino to control the SSR, no? D11 in the diagram above?

 

I'm confused. If you are using GRBL 0.9, you should have the pinout shown in the second photo above, which has the spindle PWM on D11 and Z axis limit on pin D12. From the info on GitHub, all 0.9 versions have PWM enabled and use this pinout.
And config.h? Are you compiling your own code? That might explain it...

 

Thanks Kyo, Northernboy, that explains it.

It's sometimes difficult to grasp this stuff for us non programmers, recompiling the code never even crossed my mind.

MG

 

Hi Guys:

I have been using Arduino Nanos on all my machine builds for 2 or 3 years now, and using Xloader to load GRBL onto the board. Been working fine, quick and much easier than the Arduino IDE. Also, I use the clone boards with the CH340 USB-SER so the Arduino IDE doesn't recognize them without jumping thru hoops.

Recently I bought 5 more board off of Amazon, and they won't program. Did something change with the AT MEGA 328? Or some other change recently? I bought boards in October, they worked fine, I bought these in April from the same manufacturer and they won't upload GRBL...

MG