Arduino and Limit Switches

I’m having issues setting up my limit switches. Multi meter is showing continuity between ground and all three (X, Y, and Z) pins (9, 10, and 12) on the Arduino. Could my Arduino be shot? X, Y and Z steppers are working fine when plugged into the gShield. Getting frustrated.

Unless you have changed active state ($5) for the switches on pins 9, 10 and 12 the pins should be about 5 volts when no homing switch is pressed. As each switch is pressed the voltage should change to zero.

Check to see if you have homing enabled ($22=1) and soft limits enabled ($20=1).

Does your machine home when you send $H to grbl?

Hi Larry… I’ve not been into the grbl settings, initial testing was all through Easel. I can tell you that the Arduino has continuity across ground and the X,Y, and Z pins out of the machine with no power. Does that sound normal? I will get into the grbl later tonight to see what is happening.

Not sure what you mean by this, but if you are measuring for continuity from pins 9, 10, and 12 to ground then that is not a valid test.

Perhaps I’m testing the wrong thing or using the wrong verbage… when I test for conductivity between ground and either 9, 10, or 12 pins I am showing a conductive connection… this is with the Arduino out of the machine and unpowered.

This is not a valid test. In order to test continuity the multi-meter applies a small voltage between the test leads in order to determine if a current will flow. Since you don’t have the Arduino powered then the electronics that implement the pins of the device cannot function properly.

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Such as?

Do the switches work (showing continuity when pressed, NO) on their own?