Who knows about simple electronics?

[Inferno]

Forgive me for asking, but are you sending command pulses to the driver, or trying to control it with switched power only?

I will have a small control panel to set the frequency of the pulses to the driver. The schematic above was, as said, very simple.
Basically the frequency generator will be on all the time when I'm using the machine. The buttons will just tell the pulses where to go.

 

[Reddinr]

Got it. So I guess the button presses will turn on/off the pulse generator, not feed the step input directly?

What I'm thinking is:
Button to turn on/off the pulse generator and a
button or switch to change direction, connected to the direction input.

Or does your pulse generator take care of that depending on the switch inputs?

 

[Inferno]

Got it. So I guess the button presses will turn on/off the pulse generator, not feed the step input directly?

What I'm thinking is:
Button to turn on/off the pulse generator and a
button or switch to change direction, connected to the direction input.

Or does your pulse generator take care of that depending on the switch inputs?

I mentioned it in the other post. The pulse generator will be pulsing all the time at a frequency I set depending on what I'm working on.
The buttons just control where the pulses go to the driver. I look at it like a running stream. Sometimes you might divert part of the stream in a different direction or even two different directions but the stream never stops flowing.

These are the pulse generators I have for prototyping.

Keep in mind that this is a hobby. I don't do anything that requires the highest quality, though I'm always trying to have better quality.

 

[pontiac428]

I'm pretty rusty, but wouldn't it be nice to use something like LabView to set up your parameters running over a cheapo china controller board via USB and an Atom pc? I'd call it a CNC ground-hop kit. Ground hopping is what we called running an engine outside of the vehicle in the Army, so it fits here. The flexibility of a system like that might be a nicer tool for versatility.

 

[Reddinr]

Ok. things are becoming more clear. So I think you are connecting the buttons to one of the pulse generators, not the stepper, right?
Those should be great for experimentation.

You might want a safety switch when you actually get things on your lathe. You don't want the cheepo pulse generator to run away and crash your Y axis because of a 0.1 cent bad part they chose. Or, maybe go to something more industrial strength for the actual implementation. The Gecko's are fine but the pulse generators might be a bit too janky.

 

[Inferno]

Ok. things are becoming more clear. So I think you are connecting the buttons to one of the pulse generators, not the stepper, right?
Those should be great for experimentation.

You might want a safety switch when you actually get things on your lathe. You don't want the cheepo pulse generator to run away and crash your Y axis because of a 0.1 cent bad part they chose. Or, maybe go to something more industrial strength for the actual implementation. The Gecko's are fine but the pulse generators might be a bit too janky.

The pulse generator just powers the switches. See the revised schematic that might help explain it.
The second I let go of the button, the signal to the driver ends. Runaway isn't something that should be a concern with this setup.
I'm going to add in limit switches eventually as well.
I also flipped the diode in this schematic.





P.S.
My eventual goal is to have the pulses controlled by an Arduino. I'll use a potentiometer to set the frequency (feed rate) and have a readout for the speed.
I'll add in a rotary switch to control individual steps to sneak up on critical measurements. For now that will still be done with handwheels.

 

[markba633csi]

Step and direction right? The step is the only one that needs the pulse- the direction is usually just high or low
Or am I missing something?

 

[Inferno]

Step and direction right? The step is the only one that needs the pulse- the direction is usually just high or low
Or am I missing something?

Dang, you're right.
I have to rethink some things.
YIKES!
That would have been a dumb mistake.

Hmm. Might a SS relay work? Or, in this instance, I could fit a simple arduino code in the middle.

 

[markba633csi]

For direction I'm guessing you don't want a momentary switch, more like a toggle

 

[Inferno]

For direction I'm guessing you don't want a momentary switch, more like a toggle

Yeah, my whole idea was to eliminate the toggle switch.
There are a few semi easy ways to get past this hurdle but it requires a little rethinking.