[john1a]

Hello Everyone!

I am preparing a laser engraver CNC for my personal projects. It's about 45cm x 35 cm so no big deal.
I have X and Y axis, X moves with 2 parallel stepper motors and Y with only one. I have 2 "easy drivers" to drive them
and get the "ster & dir" interface.
The the X motors are mounted at the first driver (set to 750mA with heatsink) and the Y motor is alone at the other driver.

When I use an arduino to command the drivers there is no problem! The motion is smooth and as it should be! The step and dir pins are in output pins and ground is at arduinos ground. As I said this works perfectly!

The problem starts with the Parallel port. I almost certainly need to use mach3 (linuxcnc has some issues with sandy bridge that i have). So I made a passive breakout of the parallel port and connected the step and direction pins at say 2 and 3 (pin 1 is strobe and not used). Nothing is happening. By a LPT Manager program I manually set 0 and 1 some out pins. I measured with a polymeter the voltage and it was ok. I even lit a LED with pin 2 and ground. But the Easy Driver won't do a thing..

Can anyone help me?

[doorknob]

You have probably already done this, but it might be a good idea to double-check to make sure that you have a common ground between your parallel port and the Easy Driver.

[john1a]

Well. it is resolved.
Strangely enough the Mach 3 altogether wasn't functioning at all. No signals to the LPT! I am not sure why, Maybe because Windows has a hard time when it is used for serious stuff (I always was Linux user)... I can't figure out why they are still selling such products when you can find better ones for FREE...

So I formatted my whole Win7 Partition and kept around 8gigs for a LinuxCNC try. The thing is that it worked (after tweaking some things in BIOS)! So I measured latency, stepconf-ed and everything runs smoothly now! Easy Driver Rules in Value for Money!

Really thanks for your answers and time!


P.S 1: Yes, I had a common ground from the LPT to the Easy Driver!

P.S 2: Just because I had a really bad time looking for Easy Driver and LPT compatibility and connection I will write here some things about the way I did the job for the generations to come! (I hope this thread to be accesible with a relative google search)

So Easy Driver can DIRECTLY be connected to the LPT (parallel port). I mean DIRECTLY. No (isolated, buffered) Breakout Boards, no diodes, no resistors, no anything! Let's make this clear. So take the dir and step pins and stick them to any output pin of the LPT. You don't even need to change the Easy Driver "input voltage" from 5v to 3.3v by soldering a jumper on it (version 4.4 here).
When configuring the steppers I made it work precisly with "Driver microstepping" at 32. Don't ask why, that's it. After that every milimeter was correct and precise. I used small (low price) motors (model: "28BYJ-48 – 5V") and did the job perfectly.