unicornswag
Newbie level 2
So I recently built a small CNC mill with a few salvaged unipolar steppers. For my driver, I'm using a L297 stepper driver and ULN2003 darlinton for each motor (Currently just on solderless breadboard). Right now, I have it hooked up to my Arduino running GRBL firmware with some short jumper wires and all seems to work well. The only slight issue I've noticed is that if I touch the end of the "step" pin jumper with my hand, the driver interprets it as an active low signal and the motor advances a step. I guess thats not really an issue as long as I just dont touch the pins
The problem came when I attempted to connect my machine to the parallel port of my laptop running LinuxCNC via a roughly 10' long parallel cable. Apparently there is so much mass and length to the cable's conductors that they flutter between acting as grounds and picking up static. so basically what I get is when the cable is connected to my L297's, whether its plugged into my laptop on not, my steppers start jittering erratically.
I'm not really sure what I could do to solve this problem, short of connecting another set of darlingtons before the input of the driver, using pull-down resistors. Maybe it has something to do with my sense voltage? any suggestions would be great!
The problem came when I attempted to connect my machine to the parallel port of my laptop running LinuxCNC via a roughly 10' long parallel cable. Apparently there is so much mass and length to the cable's conductors that they flutter between acting as grounds and picking up static. so basically what I get is when the cable is connected to my L297's, whether its plugged into my laptop on not, my steppers start jittering erratically.
I'm not really sure what I could do to solve this problem, short of connecting another set of darlingtons before the input of the driver, using pull-down resistors. Maybe it has something to do with my sense voltage? any suggestions would be great!
