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A axis will only run one way
« on: November 05, 2017, 12:10:57 PM »
I use the A stepper motor on my lathe ATC to turn the 8 tool turret.
Tool no 1 is set to 0, tool no 2 is set to 25.5 etc. Everything works well if i go from tool 1 to tool 2 until tool tool 8. Then problem starts when going back to tool 1, the turret continue the same direction, not in reverse. After the tools will not end up where it should.
It is Mach3 turn with paralell port. X and Z axis works well.
What have I done wrong?


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Re: A axis will only run one way
« Reply #1 on: November 05, 2017, 12:36:04 PM »
Hi,
as an experiment try checking (unchecking) the Active Low for the Dir pin for that motor. If it then goes in the opposite direction then there is a fault
in your BoB or PP setup, if it doesn't go the other way then there is a fault in the driver.

Craig
My wife left with my best friend...
     and I miss him!
A axis will only run one way
« Reply #2 on: November 05, 2017, 02:15:43 PM »
Thank you Craig
I changed the Active Low for the Dir pin, still the same direction. I also switched the cable and used one of the other drive, still only one direction.


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A axis will only run one way
« Reply #3 on: November 05, 2017, 02:26:14 PM »
Thank you Craig
I changed the Active Low for the Dir pin, still the same direction. I also switched the cable and used one of the other drive, still only one direction.


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I have a limit switch in the ATC that is set for tool no 1. In the macro I have Code("G28 A0") to home tool 1 this do not work. The switch is set as home for motor A. Is the G code wrong?


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Re: A axis will only run one way
« Reply #4 on: November 05, 2017, 03:30:38 PM »
Hi,
Quote
I changed the Active Low for the Dir pin, still the same direction.
tends to make me think that the driver is faulty.

Could you explain in a little more detail:
Quote
I also switched the cable and used one of the other drive, still only one direction.

I think that G28 A0 code will send the machine to machine zero via A0. Is that what you wanted?
G28 is not commonly used in Gcode programs.

Craig
My wife left with my best friend...
     and I miss him!

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A axis will only run one way
« Reply #6 on: November 06, 2017, 10:20:47 AM »
Hi,
Quote
I changed the Active Low for the Dir pin, still the same direction.
tends to make me think that the driver is faulty.

Could you explain in a little more detail:
Quote
I also switched the cable and used one of the other drive, still only one direction.

I think that G28 A0 code will send the machine to machine zero via A0. Is that what you wanted?
G28 is not commonly used in Gcode programs.

Craig
I tried the X drive on the A motor but still only one direction.

I want the X motor to home to the home switch by G28. What code should I use. The ATC has a pneumatic cylinder that open than wait a few sec than turn the motor until it hit the home switch. This should happen every time tool no 1 is selected unless the home switch is triggered.
Gaute


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A axis will only run one way
« Reply #7 on: November 06, 2017, 12:11:06 PM »
Hi,
Quote
I changed the Active Low for the Dir pin, still the same direction.
tends to make me think that the driver is faulty.

Could you explain in a little more detail:
Quote
I also switched the cable and used one of the other drive, still only one direction.

I think that G28 A0 code will send the machine to machine zero via A0. Is that what you wanted?
G28 is not commonly used in Gcode programs.

Craig
I tried the X drive on the A motor but still only one direction.

I want the X motor to home to the home switch by G28. What code should I use. The ATC has a pneumatic cylinder that open than wait a few sec than turn the motor until it hit the home switch. This should happen every time tool no 1 is selected unless the home switch is triggered.
Gaute


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I put in G28.1 in the code than homing works. Than tool no 1 to 8 works ok as long as I go up in the numbers. I can than put in the M code for tool no 1 and than the tool next in the program if I need to go down in number
Re: A axis will only run one way
« Reply #8 on: November 06, 2017, 12:55:03 PM »
Hi,
do you have a multimeter and can you get in there to probe the DIR pin of the driver?

I think the code issue will resolve itself IF you can get your motor to drive both ways. Can you MDI the motor in such a manner to test the Dir pin
from your controller?

Craig
My wife left with my best friend...
     and I miss him!
Re: A axis will only run one way
« Reply #9 on: November 07, 2017, 01:23:06 PM »
Thanks a lot Craig
Your guidance led me to the problem. The dir pin did stay low in both directions. When changing to an other pin on the BOB the problem was solved.
Now all my tools are set and correctly in the tool table and works perfect! :) ;)