Re: Gecko 201 drives, can I drive them directly with a Parallel port on my computer

Jim,

Geckos require 16milliamps to work, the parallel port delivers 10
milliamps per pin. The reason why geckos will work ok with 10
milliamps is because the tolerance of the optoisolators used. So you
just have to be lucky enough to a set of geckos with optoisolators in
the right range. This is the main reason why you should get a
breakout board that buffers the signals.

Arturo Duncan
http://cnc4pc.com

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Jim Dubois" <jdubois@...>
wrote:

>
> I have a problem with Gecko drives not working, I am assuming I

have

> done something stupid or have overlooked something....or will a PC
> parallel port not actually "sink" the required 16ma? I have used
> the parallel port for control of many drivers, but for what ever
> reason the Geckos are not working. This is my first effort with
> Gekos....
>
> I have replaced a set of IMS drivers on a formerly functioning
> controller with new out of the box Gecko 201 drivers. I have +65
> vdc, tied to a chassis ground, I have +5vdc for the common terminal
> on the drives, also tied to chassis ground. The parallel port,

also

> grounded properly, is communicating with the controller as I can
> turn on and turn off the aux devices, ie spindle, coolant and the
> like. The power light is "on" on the drives, the motors "lock".
> Current setting on the drives is at default, 7 amps. No connection
> to the "disable" connection. There are no limit switches or other
> complexity...just a 3 axis controller with 2 aux's and the aux's
> work.
>
> I have checked out the controller with a different computer, no
> change. I have verified the +5vdc to common stays steady. I have
> not been able to verify the TTL signals, no scope or logic trace
> tools in house. But, it worked with the IMS...so...I would think

it

> would work with Gecko.....
>
> any thoughts? do I need a parallel port interface card to drive

the

> Gecko's?
>