[jmsiefer]

I purchased a USB CNC board, and am having issues getting it to drive my steppers correctly.
Here is exactly what I've done to try and get it to work so far:

1) I purchased a USB CNC board off of AliExpress.
4 Axis USB CNC Controller Interface Board CNCUSB MK1 USBCNC 2.1 Substitute MACH3-in Motor Driver from Industry & Business on Aliexpress.com

I installed the software and connected a 4-wire 3VDC stepper motor to the X-Axis connectors on the board. I then ran some sample GCode that came with the software, however I then realized that since the only power it provides is from USB, it wouldn't move the steppers. (Duh.)


2) I purchased 3x of these guys to "bump up" the power: "A931A CNC Router Single Axis 3.5A TB6560 Stepper Stepping Motor Driver"
A931A CNC Router Single Axis 3.5A TB6560 Stepper Stepping Motor Driver-in Motor Driver from Industry & Business on Aliexpress.com

Here is the manual for the board: http://blog.pennybuying.com/down/a/A931A.pdf

Right now I'm just working with just one of the boards (for the X-axis), and I'm powering it with a +24volt @ 2.5A power supply.

This time, when I ran the sample GCode, I used a 12volt motor. Now it began to spin when it was supposed to, however it only moved in the X+ direction. I then stopped it, and tried jogging just the X-Axis. When I tried moving in the X- direction, it wouldn't go. It would only move X+. Very odd. I also noticed that that the motor was getting SUPER hot (probably because so much power was going to it now).

3) Here is a photo of my setup: https://www.dropbox.com/s/fxtzkh54c5...NC%20Setup.jpg

So, that's my situation. My USB CNC Controller works, but only in one direction. Any suggestions on how I correct my setup?

Thanks!

[doorknob]

What are the labels of the four output terminals from the USB board that you have wired to the driver input terminals?

[jmsiefer]

The USB CNC board lists terminals for the X-Axis as: |CP|CW|-|+5|

On the "A931A CNC Router Single Axis 3.5A TB6560 Stepper Stepping Motor Driver", one side has terminals listed as: |-voltage input|+voltage input|B-|B+|A-|A+|.
I connected a stepper motor with Red, Yellow, Black and Grey wires to these contacts as follows: I connected the Red wire of the stepper motor to |B-|. I connected the Yellow stepper motor to |B+|. I connected the Black wire to |A-|. I connected the Grey wire to |A+|.

On the opposite side of the "A931A CNC Router Single Axis 3.5A TB6560 Stepper Stepping Motor Driver", the terminals are: |+V|Pul-|Dir-|EN-|.
I ran a wire from |+V| on the Motor Driver to |CP| on the USB board. I ran a second wire from |Pul-| on the Motor Driver to |CW| on the USB board. I ran a third wire from |Dir-| on the Motor Driver to |-| on the USB board. And then last, I ran a wire from |EN-| on the Motor Driver to |+5| on the USB board.

Like I said, the motor "seems" to run correctly, but it's only driving in one direction. Very odd.

[doorknob]

The USB CNC board lists terminals for the X-Axis as: |CP|CW|-|+5|

On the "A931A CNC Router Single Axis 3.5A TB6560 Stepper Stepping Motor Driver", one side has terminals listed as: |-voltage input|+voltage input|B-|B+|A-|A+|.
I connected a stepper motor with Red, Yellow, Black and Grey wires to these contacts as follows: I connected the Red wire of the stepper motor to |B-|. I connected the Yellow stepper motor to |B+|. I connected the Black wire to |A-|. I connected the Grey wire to |A+|.

On the opposite side of the "A931A CNC Router Single Axis 3.5A TB6560 Stepper Stepping Motor Driver", the terminals are: |+V|Pul-|Dir-|EN-|.
I ran a wire from |+V| on the Motor Driver to |CP| on the USB board. I ran a second wire from |Pul-| on the Motor Driver to |CW| on the USB board. I ran a third wire from |Dir-| on the Motor Driver to |-| on the USB board. And then last, I ran a wire from |EN-| on the Motor Driver to |+5| on the USB board.

Like I said, the motor "seems" to run correctly, but it's only driving in one direction. Very odd.

My interpretation of the axis output terminals of the USB CNC board is:

CP = step pulse output
CW = direction signal output
- = ground
+5 = +5 volts

My interpretation of the input terminals of the TB6560 driver board is:

+V = supply +5 volts to this terminal
Pul- = step pulse input (active low)
Dir- = direction signal input (active low)
EN- = enable signal input (active low)

So if my interpretation is correct, it appears that you have wired:

CP step pulse output to +V 5-volt power supply input
CW direction signal output to step pulse input
ground to direction signal input
+5 volts to Enable signal input

(which does not appear to be a proper way to wire things up)

[jmsiefer]

CP step pulse output to +V 5-volt power supply input
CW direction signal output to step pulse input
ground to direction signal input
+5 volts to Enable signal input

Yes, that is correct. How would I wire it correctly?

THANK YOU SOOOOOOOOOOOO MUCH FOR HELPING ME WITH THIS!!!

[doorknob]

Based on the info that you have provided, I would suggest trying the following hookup:

CP (step pulse output) to Pul-
CW (direction signal output) to Dir-
-(ground) to EN- (enable)
+5 volts to V+

As far as the motor getting hot, what is the current rating of the motor, and what current did you set the TB6560 board for?

[jmsiefer]

I just tried that new setup, but unfortunately now it doesn't move at all. I restarted my computer and the program, just to double check. Hmm... Any suggestions for an alternate wiring configuration?

RE: the motor getting hot- It's a crappy motor. I have a few like it, so even if it totally burns up, I'm not too worried, hahah....

[doorknob]

Try removing the wire from EN- to ground.

If that doesn't work by itself, try connecting EN- to +5 volts (the way that it was connected before).

While the labeling implies that EN- must be connected to ground, the fact that you previously got some movement when EN- was connected to +5 volts implies that the labeling on the TB6560 board may be incorrect.

[jmsiefer]

Yup, wired it back to the original way, and it's running again. Still only in the X- direction... but it's running.

(I wrote this before seeing your #9 post. Trying that new config now. Thanks!)

[jmsiefer]

Removing the EN- to ground wire completely, allowed me to press the jog button inside the software and finally receive a response. Unfortunately, the motor would spin in the same direction if either the X+ or X- jog buttons were pressed.

Connecting EN- to +5 volts (while V+ was also connected to +5 volts) showed a similar response, where both jog buttons would make the motor spin in the same direction.

I think we're getting close here though.

[doorknob]

Do you have access to a multimeter (and know how to take a voltage measurement)?

If so, measure the voltage between the CW terminal and ground while you jog the axis in one direction and then in the other direction.

It should be close to +5 volts in one direction and close to 0 volts in the other direction.

If the voltage does not change when you change jogging direction then that would explain why your motor does not change direction, and you would need to direct your attention to the behavior of the USB board (and perhaps see if there might be some configuration setting that must be changed, if the board actually has such settings).

[jmsiefer]

Yup. When I connect the multimeter between CW and ground on the USB board jogging in the X- direction registers as 0 volts. Jogging in the X+ direction registers as 5.3 volts.

[doorknob]

Then that sounds like the USB board is working properly, which also implies that the TB6560 board is not.

To troubleshoot from this point, I would first double-check that the wire is making a good connection to the dir- terminal. If that is OK, then I would use the multimeter to follow the dir signal all the way from the input terminal to the direction pin of the TB6560 chip, looking for the point in the circuit where the expected voltage change does not occur.

For example, just by looking at the board photograph, it appears that the dir signal goes into an optoisolator chip, so I would try to find a datasheet for that part (by looking up the part number on a site such as datasheet.net - I'm not sure that I can read the part number correctly from the photograph, it might be a 4N25), figure out which terminals are for inputs and outputs, and so forth, and if that looks OK, follow the circuit all the way to the TB6560 pin - you can probably identify the right TB6560 pin by looking up the TB6560 datasheet from datasheet.net as well. The optoisolator may invert the signal (or it may not, depending on the way that it is wired). Note that the step signal probably also goes through an optoisolator, so you would have to examine the circuit board wiring traces carefully to determine which one is for which signal.

[jmsiefer]

Maybe the stepper wire configuration isn't correct...? Do you happen to know the config for Red, Yellow, Black and Grey? It's a Portescap stepper (S42L048S02-M5) 24volts. 5 ohms.

[doorknob]

I do not know the wiring configuration for that motor (you could figure it out by measuring lead resistances with the multimeter), but if it is stepping then it's extremely likely that you have it hooked up correctly, and it's unlikely that the lack of direction change is due to hooking it up improperly.

[jmsiefer]

HOLY GUACAMOLE! I switched out the stepper just to see if it might help, and it seems to be jogging correctly in both directions now. My config is the second one you suggested, where I have CP to Pul-, CW to Dir-, +5 to +V, and +5 to En-.

THANK YOU SO MUCH FOR WORKING THROUGH THIS WITH ME! OH MAN... I would have been COMPLETELY LOST if it hadn't been for your help. I sincerely appreciate you taking the time for this, and having the patients to explain it all to me. YOU'RE THE BEST!!

[doorknob]

Glad to hear that it's working...