M542T Stepper Drivers

I am having trouble controlling M542T stepper drivers with Smoothie. I can control motors using Smoothie’s onboard drivers with Pronterface. I wired the drivers as shown for the DQ860MA. I also increased microseconds_per_step_pulse = 2 in the config file because the M542T datasheet recommends a 1.5 micro-second pulse as a minimum. Also, I’ve added a logic converter to convert Smoothie’s 3.3 VDC signal to a 5 VDC signal for the M542T. The motors engage, but will not move. Can anybody help?

Imported from wikidot

Can we see a picture or schematic of exactly how you wired them ?


Do you think the problem could be associated with the 5 V ground? I wonder if my 5 V ground should connect directly to HV4.

I meant to say the 5 V ground to HV1.

I think you just want gnd to be shared all around.


I got it working! Here’s the schematic if anybody else needs to connect Smoothie to an M542T.

Hi clau0086 and authurwolf-

I am also using a M542T with my smoothieboard. I have it connected just as you have pictures, without the logic converter. I am able to get my NEMA23s to move just fine using the 800 pulse/rev DIP setting (5,6 ,7,8 are ON OFF ON ON). The reason I am posting on the smoothieboard forum is that I can’t get the motor to pull more than 0.61A at 30VDC power. I have the motor setting(gamma_current) at 4.5 A in config and in config_override — I have tried changing microseconds_per_step_pulse to 3, 5 and 10 to see if this might be an issue. I have also gone through all of the pulse/rev DIP settings — though I got some funny sounds, the draw was never more than 0.61A. Anyone have an idea why this would be? Is this related to the need for a logic convertor? I will get one regardless, but I figured since I can get the motors to move at low current (which means low torque unfortunately) that the signals were getting through, and the supply power would be governed by the 542T unit only. Thanks in advance.

The “gamma_current” setting in Smoothie has no meaning when using external drivers, it is only about the internal drivers.

To set current on an external stepper motor driver, you must change DIP settings on that driver.

Ah, I thought as much. Thanks for the quick reply arthurwolf. I am still having the issue even though I should be getting up to 4A/phase but this is a 542 problem.