Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: sparkyengle on June 07, 2016, 10:29:17 AM

Title: Motors won't change direction
Post by: sparkyengle on June 07, 2016, 10:29:17 AM

Hopefully this is a simple one. I'm trying to convert an old Microkinetics SuperDrive over to Mach. I can get the motors to turn, but they won't change direction. Any ideas? Thanks in advance.

Title: Re: Motors won't change direction
Post by: Tweakie.CNC on June 07, 2016, 11:28:20 AM

Just a guess in the dark...
Perhaps check the voltage on your axis Direction pins. (If they are to the 3.3Volt TTL standard and your drive requires the full 5Volt TTL then maybe ?).

Tweakie.

Title: Re: Motors won't change direction
Post by: joeaverage on June 08, 2016, 04:20:18 AM

Hi,
another possibility along the same lines as Tweaky is that some drives require an active direction input, for instance
if the pin is left floating it will naturally go high and therefore turn CW say. It will require your BOB to pull the direction
pin low to get it to turn CCW.
Careful reading of the drive and BOB manuals are required, my experience is that they are not plug and play!

Craig

Title: Re: Motors won't change direction
Post by: sparkyengle on June 14, 2016, 01:54:34 PM

Thanks Guys. I added a cheap ebay Breakout board into the mix and it took care of it. It was looking for both the ground and +5v from the computer to work.

Title: Re: Motors won't change direction
Post by: joeaverage on June 15, 2016, 04:43:01 AM

Hi sparky,
a good BOB is really worth its weight in gold, some if not most have LED's on the outputs. Makes diagnosing
faults and setup issues SO much easier and less prone to slipping with a multimeter probe and wrecking
something!

Craig

Title: Re: Motors won't change direction
Post by: rcaffin on June 22, 2016, 12:59:21 AM

a good BOB is really worth its weight in gold, some if not most have LED's on the outputs.
Indeed!

Cheers
Roger