Re: [CAD_CAM_EDM_DRO] gecko for notebook

JanRwl@... wrote:

> In a message dated 9/17/2002 10:28:55 PM Central Standard Time,
> alex0young@... writes:
>
> > How do I control a gecko driver from a notebook with very limited
> > ports? From where can I get the +5V for the gecko?
>
> Then test your "notebook" to see if it can SOURCE 15 mA per bit, and strap
> the Gecko jumpers for +ve INPUTS, common ground.

No way! Don't even bother to test this. No notebook, and no desktop system will
source 15 mA from the parallel port. Some will source about 1 mA, and good ones
will sink 8 - 10 mA reliably. Since you don't need exact logic voltages when
driving opto-couplers, you may be able to sink enough to drive an opto-coupler
that needs 15 mA, but I would not count on that. Good opto-couplers will work
well on 5 mA, and will last a lot longer at that current rating. Most opto-couplers
are only rated for 10 mA maximum on the LED.

>
> Isn't there a "serial port" or an "external video port" or "joy-stick port"
> in addition to the LPT-1? The S.port has +5 VDC!!! Enough for this
> purpose.

The serial port does NOT provide a 5 V output. You can program some of the
control lines to provide a few mA of positive voltage, but they can provide a
NEGATIVE voltage at other times on the same pins, if not programmed right.

The external keyboard connector and the PS/2 mouse connector DO provide
a 5 V supply that should handle the opto-coupler drain. (After all, the mouse
has a bunch of opto-sensors in it.)