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Author Topic: Motor locks, but no turning.  (Read 3161 times)

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Motor locks, but no turning.
« on: June 15, 2015, 12:08:48 AM »
I've seen this question lots of times, but no answers :( so I'm hoping if I tell you what debugging I've done I can coax out an answer.

the setup:
OS: Win XP sp3
3gb ram
core duo 6500

to parallel port
CH352 Pci -> parallel (Driver installed and working)
port 9800

The Driver board
TB6560 4 axis (yes I'm aware of the issues of this board)

why I think the issue is in mach3:

I can manually turn the motor with this setup by using LPT port test utility (a piece of software that allows you to manually select what pins to make hi-lo)
I can make D2 (pin4) High to activate the X axis
I can rapidly click INIT(pin16) to make the motor step on the falling edge
I can select Strobe (pin1) to change Direction of the steps.

Plugging these numbers into mach3 mill (plus all the additional ones)
the stepper locks up (activates) when I hit the Reset button, so I know Mach 3 is communicating with the board & using the correct pin(s)
depending on if I have the step pin set to activate on the falling or raising edge, I can see the 'Active" LED come on (it's on whenever the step pin is high)

however, despite having played around in the motor setup, tried different frequency's, but I just can't get the motor to step, heck, I can't even hear the tell-tale whine of a high speed PWM running.

I have an oscilloscope if needed, but seeing that it works just fine with the other software, I don't think I should need it.

when I DID play with my oscilloscope in mach 3 (before I hooked up anything, when I was still setting up my parallel port) I noticed mach 3 uses a very short pulse time.

My thought: the pulse time is to short, and the frequency of the TB6560 is to low to catch it.
although even that seems unlikely to me, since even basic 7400 logic IC's can pick up on those blips, so I would assume the TB6560 could do so as well...

what are your thoughts? I'm to tired and my brain isn't working anymore...

Thanks in advance!

Offline Tweakie.CNC

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Re: Motor locks, but no turning.
« Reply #1 on: June 15, 2015, 03:51:53 AM »
There are a number of different 'so-called' TB6560 boards and they each behave slightly differently. Quite honestly, they are hardly worth wasting time over - however, just a few suggestions...

Check that your parallel port output is to the 5 Volt TTL standard as opposed to the 3.3 Volt TTL standard.
Change the Mach3 Active High / Active Low state of the step pins and see if that makes a difference.
Check that the Mach3 keyboard jog buttons are not disabled.
Check your PSU voltage and current availability to the board.
Check that the board's motor drive current DIP switches are set to match your motors.
Use a multi-meter just to re-check that you are connecting your motors correctly  ( A - a / B - b ).

There are many settings within Mach3 that are important for correct operation so it may be wise to read the manual through a couple of times to see if there is anything you have missed.

Tweakie.
 
KEEP SAFE !
Re: Motor locks, but no turning.
« Reply #2 on: June 16, 2015, 11:22:47 PM »
Just some video footage of the problem:
https://www.youtube.com/watch?v=t77r3fFm5aY


"There are a number of different 'so-called' TB6560 boards"

mine is the same as shown here: http://www.ebay.ca/itm/TB6560-CNC-4-Axis-Stepper-Motor-Driver-Controller-Board-for-Engraving-Machine-/221423173993?pt=LH_DefaultDomain_0&hash=item338dd98169
(the pinout on the documentation is wrong, here is the correct setup (double checked myself) : http://forum.seemecnc.com/viewtopic.php?f=22&t=49

"Check that your parallel port output is to the 5 Volt TTL standard as opposed to the 3.3 Volt TTL standard."

-Nope, it's 3.3v unfortunately but this doesn't seem to be the issue (see vid)

"Change the Mach3 Active High / Active Low state of the step pins and see if that makes a difference."

-tried, no diffrence

"Check that the Mach3 keyboard jog buttons are not disabled."

-Checked, not disabled.

"Check your PSU voltage and current availability to the board."

-15A @ 24v (turned down to 23v) is plenty of power.

"Check that the board's motor drive current DIP switches are set to match your motors."

-set to %100 which seems fine (doesn't seem to have made a difference changing it)

"Use a multi-meter just to re-check that you are connecting your motors correctly  ( A - a / B - b )."

-done & done



EDIT: fixed it! (sorta) I changed the pulse time from '0' uS to '15' uS (even 5 didn't work) but it's finally working! (not smoothly by any means, but that's tweak-able)

Video of that http://youtu.be/m41DB9qVCxk