GRBL and Arduino Sketch Serial Communication

Projects General Guidance
1

I am trying to combine GRBL's stepper motor control with Arduino sketches. Does anyone know if it is possible for an Arduino sketch to send commands to GRBL? I have an Arduino Uno with both the GRBL and Arduino bootloaders. When I go into Arudino's serial monitor I can type the g-code command "G91 G0 X1" to GRBL and my machine moves 1 mm to the left. When I upload a the following sketch, nothing happens,

void setup(){
  Serial.begin(9600);
}

void loop(){
  Serial.write(“G91 G0  X1\n\r”);
  delay(1000); 
}

Thanks in advance.

2

Have you two Arduinos, one running GRBL and one running your sketch?

If so please describe how they are connected, and what sort of Arduinos you are using.
...R

3

Thanks Robin for the quick response.

Right now I am using one Arduino. I was hoping there would be a way to communicate between the GRBL and Arduino bootloaders on a single Arduino. If this is not possible, I plan to trying a setup with two Arduinos next.

4

Hi,
could you move your machine by typing on Arduino's Serial Monitor? If so, did you use a special library and made your own code through the library?
I have a similar problem. I want to move a CNC machine through Arduino. I thought to use the Serial Monitor, but I don't know how to send the G-codes to the machine. If you can help me.

Thanks

5

dbarbosa:
I have a similar problem. I want to move a CNC machine through Arduino. I thought to use the Serial Monitor, but I don't know how to send the G-codes to the machine. If you can help me.

This is like "how long is a piece of string?"

GRBL is a program that controls a CNC machine through an Arduino. I haven't used it but I understand that it takes G Code as its input.

If you don't want to use GRBL there is nothing to stop you writing your own code to interpret G Codes and control stepper motors.

My own interest is in using my PC to convert the G Code into step and direction instructions that the Arduino can use to control the stepper motors through a simple Arduino program.

And of course there is no reason why you could not develop an alternative to G Code if that's what you want.

This demo shows how to use a Python program on a PC to communicate with an Arduino. There is also a JRuby version for those who prefer that. The Arduino code will also work with input from the Serial Monitor.

I guess you need to decide what you want to do.

...R