RE: [CAD_CAM_EDM_DRO] question for Mariss

This point seems to get many people even though it is very simple. Seems
we just have the idea stuck in our head that signal wires always have to
be + voltage and the supply to them ground.

Gecko G201 and G320 drives ALWAYS use +5 v on the logic common pin. This
+5 V MUST be from a source that is grounded to the parallel port or the
drive will not step. If you use the +5 V from an unused drive connector
in the computer, the game port, or the USB port it will already be
common on the ground side to the computer (meaning if you put a DVM
between the +5 V supply and a ground on the parallel port you actually
get a reading of 5 V. If you do not get a 5 v (or darn close) reading
than the drive will not step). If you choose for some crazy reason to
use an external +5 V supply you MUST connect the ground of it to the
computer for the drive to work and other than making things more
complicated did absolutely nothing positive.

The G210 and the G340 allow you to change the meaning of the logic
common so that it can be +5 V (identical to the way a G210 and G320
work) or it can be ground.

Now is everyone clear on the connections?

Here is what you have with a G201/G320 or a G210/G340 set to +5 V
common. The common terminal on the Gecko is one end of the step and
direction optos. The step pin and the direction pin are the other ends.

--+5v-----------
| |
Step Dir (opto in drive)
| |
| |
Step Dir (parallel port Pin)

Now when the parallel port pin goes low (0 v or ground) current flows
through the opto and it lights. When the parallel port pin goes high (+5
V) there is no potential across the opto so no current flows and the
opto is dark. OK, everyone get it. This means the opto is active
(lights) when the parallel port is low.

Here is what you have with a G210/G340 set to 0 V (ground) common. The
common terminal on the Gecko is now the opposite end of the step and
direction optos. The step pin and the direction pin are the other ends.

Step Dir (parallel port Pin)
| |
Step Dir (opto in drive)
| |
| |
--0v (ground)----


Now when the parallel port pin goes low high (+5 V) current flows
through the opto and it lights. When the parallel port pin goes (0 v or
ground) there is no potential across the opto so no current flows and
the opto is dark. OK, everyone get it. This means the opto is active
(lights) when the parallel port is high.

Tim
[Denver, CO]
Sherline products at Deep Discount
Mach1 & DeskCNC with credit card ordering
www.KTMarketing.com/Sherline
Now selling Visual Mill 4.0 Special price $1200

> -----Original Message-----
>
> when i review the documentation for the drives, your specification
> page refers to a +5vdc ,but on the physical drive itself that
> particular position says "common" what does this mean?
> i also downloaded a wiring schematic created by Donald Brock
> that outlined a typical gecko g320 mock-up. here he has the
> +5vdc from the computer hooked up to the corresponding
> +5vdc/common position on the drive. can this position be
> +5vdc or ground ? do you know what pins and ports will
> provide +5volts?
>
> thanks for you help.

> FAQ: http://www.ktmarketing.com/faq.html