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Does anyone know if/how I could connect this stepper motor controller to the parallel port of my computer? Answered

The controller came out of a large industrial copier machine. It uses a SLA7026M stepper motor controller. The motor that it runs is rated for 24 volts. I am unsure of the amperage.


in A, in (overscore) A, in B, in (overscore) B

I have a photocoupler for the parallel port with its own individual power supply rated for +5v dc 3A, and it tells me where each individual pin is, so I want to figure out which pin the controlling inputs/outputs have to be connected to in order to be able to control the motor from my computer, and which wires will input the power for the motor to run off of.


6 years ago

So......  the SLA7026 pdf uses a minimum 7 wires Ground, motor power,
logic power and four logic drives A, a, B, b,.
Leaving 1wire for logic drive for current reduction ( hold ) control.
This accounts for 8 wires.
If you read the PDF you will find the 7026 can supply 3A at 46VDC.

Can't tell you which wire is which, even from a good pic.


Would it be right to assume that the power wires would be soldered to a wider "track" on the circuit?
Also, would you be able to tell (via tracing, or maybe i could do it myself) if i gave you a good pic of the underside of the board, labeling the controller's pins, and the input (from/to computer) and output (to motor)?

Top and Bottom views, Here is a superb reverse eng ible.

That takes time I can't promise full success, I will look at it.


Here are the pictures.
If they did not work, are unclear, or you need clear pictures of certain sections of the circuit, let me know.


Sorry, after two hrs can't see enough to even trace the motor.
You have the hadw follow the ible I pointed to and
try to trace a service manual for RICOH assembly No not in focus.

Ok, thanks for making the effort!
I will try the ible....

Why do you want to connect this to a parallel-port?


To use it with software on my computer in order to control a stepper motor for a cnc.

Your wanting to use the parallel port as a data-link, so the device would need a separate power-supply.
Do you know which logical-inputs you need to control for it to work?