Stepping AND Direction pins need to be closely timed.
If the Arduino spits out a direction high and stepping signals, and there's a delay of the direction pin, there will be a few counts by the Arduino assumed in the wrong direction.
Seriously, you already saved yourself stepper motors and stepper drivers, just get a proper Arduino with more IO.
The few bucks you spend on it will save you so many headaches.
You will have enough to do calibrating the printer to print and calibrating steps/flows/temperature,
You don't want to me messing around with shift registers, and modifying the firmwares as well.
If the Arduino spits out a direction high and stepping signals, and there's a delay of the direction pin, there will be a few counts by the Arduino assumed in the wrong direction.
Seriously, you already saved yourself stepper motors and stepper drivers, just get a proper Arduino with more IO.
The few bucks you spend on it will save you so many headaches.
You will have enough to do calibrating the printer to print and calibrating steps/flows/temperature,
You don't want to me messing around with shift registers, and modifying the firmwares as well.