Gecko 5V supply using game port/ XY joystick jogging

jvicars@... wrote:

>The Gecko 201 manual says that the 5V for step and direction must come
>from the indexer/pulse source. I.E. the computer. Can you get 5V through
>the parallel port somehow, or do you have to run a 5V line from the
> computer to the drivers? Anybody have advice on how to hook this up?

mariss92705@... wrote:

> Most PCs have a game port. The +5VDC is available on .. the game port.

Hi Joe:

This is exactly (among others) the reason why I recently (March 28/2001)
announced how to wire up the pBREAK to the game port - see diagram at:

http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/CIRCUITS/parallel_to_gameport_pinout.gif

To review - the 25 pin parallel port is broken out into a ground, 12 output bits
and 5 input bits, leaving 25-18= 7 redundant ground lines in the parallel cable.
If we tap into the game port, we can get +5 & GND extremely neatly.

The +5 is sent down the parallel cable, and is available to the Gecko's at
the far (equipment) end, where you breakout the signals there to the Gecko
+5, GND and logic signals.

That answers your question on where to get the +5 for the Gecko's
(or various other purposes). See my website for a picture of a
parallel/gameport wired setup for exactly this purpose.

- - - -

However, if I may ramble, there are a total of four additional input bits
and four input potentiometers on the gameport, which we now have nearly
free access to. We can use the four additional input bits, and we can also
use one (of the four) potentiometers for (say) feedrate over-ride (but we'll
need to wait for the software guys to implement that).

Using 2 pots for XY joystick control:
Or perhaps, use two lines for two potentiometers (leaving 3 input bits).
Or perhaps, skip the GND (use the parallel port GND), use two input
pots and 4 input bits.

I understand EMC is close to supporting XY joystick jogging.

If it were me implementing the control panel, I'd keep the X pot separate
from the Y pot (rather than combined into a single joystick), so that
linear manual moves in one axis (say X) don't result in accidental moves
in the other axis (ie you might get a jog instead of a straight cut!).

Doug Fortune
http://www.cncKITS.com