Gecko 5V supply using game port/ XY joystick jogging

Hi Tom:

I agree with all your points, but not your conclusion: see below

"Tom Eldredge" <harmonyt@...> wrote:

>Game port pot use? Some things to consider:
> The newer computers are dropping the game port in
> favor of USB, are they not? The newer computers are dropping the ISA slot too.

I haven't seen one yet with no gameport, but thats besides the
point. The point is that we will have a future 30 year supply of
older computers WITH a gameport.

>The pot control of the game port is very crude, and unreliable.

In comparision to what? If it is able to do the job (of accepting
an analog value of sufficient resolution), then that is sufficient.

Perhaps you are instead referring to the quality of the potentiometers
on a joystick. That is of course an entirely different matter - not
to be confused with the basic abilities of the PC's pot inputs.

BTW, due to a number of suggestions from the group, I have
modified my 'parallel cable hotwired with gameport signals' standard
scheme slightly, to omit the gameport ground, and have two input
pots, and 4 digital inputs (to use as the software guys see fit). See the
.gif file uploaded to yahoo/egroups below.

However, I maintain it is a good idea to implement a 'digital' feedrate
override input by having two input bits: 'faster' and 'slower'. If the
two input are on a rocker (central neutral), then the user can command
a faster or slower feedrate override (the actual value of the override
is less important). Another switch, which can ground both lines
simultaneously can indicate E-STOP to the program.

"Bob Campbell" <bob@...> wrote:

>What I have done to get 5 volts is to mount a 9 pin connector on the
>PC and then use a 9 pin cable to run to my controller. The reason that
>I used a 9 pin cable is due to the low cost of the cable. I put 5 volts on
>all 9 pins in the PC.

That will work fine. Each pin on a DB9 (or DB15, etc) is good for
2 amps at 5V. Keep in mind that actually using the PC power supply
for the motor driver is to be more discouraged as the size of the
motors (&drivers) goes up. Thus its probably OK for Nema17's and
smaller, suspicious for Nema23's, and to definately be avoided for
Nema34's. Nema42's are RIGHT OUT !!!

The +5V supply we are talking about (taken from the gameport) is a
mere trickle - meant for powering logic only (or Nema 17's and smaller).

Doug
- - - - - - - -

> 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.
>

> doug wrote:
>
> 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_gam
eport_pinout.gif

> Doug Fortune
>http://www.cncKITS.com