Stepper Motor Controller Without Arduino or Microcontrollers | Simple DIY 

Hey did this end up working? any adjustments needed?

Same here.

hi, is it your circuit worked?

@@p.7555 yes, 1 switch for change the direction, and 1 button i press it to drive ,

I don’t see why not. Use your limit switches to operate some relays. Many relays have normally open and normally closed contacts. In this way I think you could have it hit the end of travel limit and either stop or reverse depending. He already showed that the motor defaulted to one direction and by toggling power it would change direction. The other option should be to kill power and stop the motor. Go find some videos on Bosch relays. And relay logic in general. I’m sure there are more elegant ways, but I’m a mechanical guy and relay logic is fairly mechanical so it suits my way of thinking.

I would think so but set your vref as to not over load your driver.

Could you explain how?

Did you find out if a Nema 34 works with the above controller?

Well, the available torque of any stepper is a function of speed (Google “stepper motor torque-speed curve”). The potentiometer isn’t having the effect you think it is though, if I am guessing the origin of your question correctly. The potentiometer is controlling not the voltage amplitude to the motor, but the voltage pulse frequency the motor driver is receiving on its control input.

Driver ic is a non programmable device since microcontroller does

And is the result are same?

Thanks!

From the data sheet. Reset and sleep pins must be high to enable driver. That's pins 5&6. The circuit that is shown in the video links 5&6, but doesn't connect that bridge to +5 Volt supply. Suggest you modify your circuit and try again. For full speed, disconnect pins 2,3,&4. Connecting those pins to 5 Volts as shown gives minimum speed, ie. 1/32 step. That driver circuit has a miniature potentiometer on it. If you start running a motor on load, you can burn it out. It's there to provide current limitation, and there is a setup procedure to follow. That will also cause running problems if set too low at the factory.

I'm not sure why it wouldn't. But I would make sure set the vref correctly as to not pull too many amps through the driver.

Pins 5&6 need to be connected to 5 Volts, or it stays in sleep mode. Give it a go.

Because he never showed you how to set the current limiting potentiometer on the DRV8825, and pins 5&6 should be connected to 5 Volts.

@@peterrhodes5663 I have set the limit of the drv8825 and have connected pins 5&6 to 5v but still not working, do you have any ideas?

@@Jordan_Fernando All I can suggest is to start substituting parts. First check the resistance of both motor coils, or connect a drill to the shaft and monitor the output, ie., drive it as a generator, disconnected from the 8825. If it seems OK, replace the 8825 assembly. If still no go, get someone to check how you have wired it up, because if you are over familiar with what you have done, you can over look an obvious wrong connection, no matter how many times you look at it. If you have an oscilloscope, check that you are getting the correct waveform at the point where the motor connects to the circuit.

@@Jordan_Fernando Just had another think about your problem. On his circuit, he left pins 1, 3, 5, and 13 of the 74HC14 open. They should be connected to ground or the 5 volt supply, whichever is easier, so have you got a square wave at pin 8 of the driver board? It's a cmos device, so all unused inputs must be connected, or strange things can happen. The motor that he is using runs on 12 volts. Are you supplying the correct voltage to yours? To make the motor run 32 times faster for any given input frequency, disconnect pins 2, 3, and 4 of the 8825 board. If you get it working, let us know, because others are having problems, judging by the comments. I've never used his circuit. DON"T GIVE UP!

Did you ever get it to work? I’m having the same problem.

Disconnect pins 2,3&4 or ground them for max speed.

yes, me too

Connect pins 5&6 to 5 Volt supply.