Sinking TTL Pulse Train on PCI 6221

[Michael_Fidler]

I am attempting to control a stepper motor controller (Applied Motion 2035-O) with a TTL output on my PCI-6221. The problem is that the controller requires a +5 VDC signal on the "Com" connection and I need to sink the TTL pulse train signal (~5mA) on the "STEP" connection.The controller moves the stepper motor one step per pulse on the postive going edge.

How do I connect this to the 6221? I also need to sink the "DIR" connection to change direction and the "EN" connection to enable the steps.

  

Message Edited by Michael Fidler on 12-08-2008 10:33 AM

[Corby_B]

Hello Michael!

Thanks for your post! I see that you are needing to sink some current to turn on the IR LED's in your circuit. It looks to me like you have a set of LED's that could have current in either direction. So instead of 5VDC on the COM input could you not just connect that to COM (D ground on the 6221) and then use three output lines to drive the STEP, DIR and EN? You could easily connect it this way.

STEP = p0.0

DIR = p0.1 

EN = p0.2

COM = D GND

This way you just set up your task as Digital Output and use timing for a specific rate. The spec is 24mA per channel so as long as you are below that you are fine. Let me know if this helps or if you need to configure this in a different configuration based on some specs I might be missing. 

Cheers!

Corby_B

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