Well, that would be a very nice thing for Gecko to put on their data sheet for the G540 if so, they don't mention that at all.

Thank you, that could certainly explain the problem.

Appreciate the help.

... but, it says TTL.
Not sure, never used one.
Better research a bit more.
I see where you posted @ Gecko, hope you get a reply soon.
I feel your frustration, wish I could help.
Russ

Yeah, also posted at CNCzone, very frustrating.

I don't think I will use a Gecko again, the documentation is just poor IMO.

Thanks for trying, the 12V may be it, but I need some transistors to amplify which I don't have on hand to try out.

That fellow on posted in that one topic .... which he started.
Never know how it all turned out for him.
You don't want to fry your Gecko !
Marcus is good, hope he gets back to ya soon.
Be cautious.
Good luck,
Russ
 

Thanks Russ.

This board has been amazing, I have gotten so much help. I cannot tell you how much it is appreciated.

That 10-30v sensor may only be acting as a regular relay in that the 12v is just operating a coil which then allows NO or NC to complete a circuit.
That circuit is just to switch the Gecko input to ground in this case.
So, you might not be supplying 5v to the input, but just switching the path to ground on and off with the sensor.

I better quit before I get you into trouble.
Russ

I got a reply on CNCZone, but I am not sure what the guy means. He said I need to sink the signal from Pin 1 on my G540, but I am not really sure what he means by that.

I'd guess "pull it to ground".
A SPST switch .... like a simple manual pushbutton in-line between the input and ground would do this.
That's the way the sketch looks to me.

Good luck, and NO SMOKE !
Russ

Ahh, well, that would make sense since I am certainly not pulling it to ground.

I thought that was what you would do with the active low setting, but this stuff is not entirely clear to me.

Thanks Russ, I am hoping for no smoke! @ $300 a board, I cannot afford to fry this thing!

Well it definitely does work if you connect the input pin to ground.

I had an old spst switch and I connected to wires to the switch, I than connected one to my ground on my G540 and the other to the input pin.

As I toggle the switch, the input light went lit and unlit.

I even was able to mock up a spindle RPM reading.

I don't know if it would work with 12V or not, I suspect not.

Challenge now is to make a switch that can connect to ground. I am not quite sure how the otto's are working as a switch or if they would allow a ground input to act as a switch.

I have some ideas about using a hall and an NPN transistor to act as a switch.