I just fried one of the stepper drivers on my cheap T6560-based driver board. I've been trying to get my BeagleBoneBlack set up to run my mill, using a Xylotex DB25 breakout board. It turns out that said board dedicates pin 1 to enable the level shifters, while my mill needs it to be X step. So I cut the trace and shorted pin 17 to pin 1.
That didn't work. Possible problem 1: Pin 17 is an output on my stepper driver board, so trying to drive it may have hurt something. I didn't see/hear any problems while testing, however, and I believe (though I haven't confirmed) that said pin was being driven previously.
My Y and Z axes work fine; so to see if my X axis is working, I plugged it into the Y axis connectors. I powered everything up and tried to jog the axis, and it moved really slowly and groaned quite a bit. Not at all what I would expect. After a couple seconds of this, I hear a pop and get that magic blue smoke out of the Y axis driver (which the X axis was plugged into; all other axes were unplugged). It turns out the bottom had blown off of the chip, so it's pretty dead.
The Y axis was working entirely fine (smooth stepping, moving at the expected speed) immediately before I attempted to plug in the X axis to that driver.
So here's my question... any idea what's wrong? Just bad timing on the driver dying, completely unrelated to my other testing? Something due to the aforementioned potential abuse? Is it even possible to do that kind of damage with bad inputs?
I just checked my stepper's coils, and all of them are ~4Ω, so I guess none of them are open-circuited, at least. I don't see (via my ohmmeter) any shorts between the coils either, so I guess it's OK, unless there's something else I could have done to kill it.
I can go try hooking it up to the Z axis driver, I suppose. Since I'm going to have to replace the board (might as well get something higher-quality- I'm not going to replace the driver on a low-quality board), I'd rather not kill the new one if the issue is somehow my stepper or inputs.
Thanks!