Re: Re: Gecko Fault/Reset Manager

The EMC parport home pin stuff is written so that when it switches
polarity it will stop any axis that is homing. With parport, you can not
home more than one axis at a time and you can not leave an axis on its
home switch while trying to home the next. That is why Frank suggests
that you need to put a home offset in your ini file so that after homing
the axis will move off the switches. There are additional ini variables
for direction and speed of the home move and for the position set when
the home sequence is complete.

With a dedicated dio board or the stg and variants you can home all
directions at the same time.

Yes, if both the switch and the index pulse go positive for the home
position, you can use a simple AND gate. An OR gate would route the
three signals to the pin but I'd be inclined to try paralleling the
output gates of the AND signals first.

Once the home sequence has completed, the EMC does not look at that pin
again so you can place your switches anywhere on the travel without
worrying about activating them.

Ray

>    From: "dakota8833" <dakota8833@...>
> Subject: Re: Gecko Fault/Reset Manager
>
> --- In CAD_CAM_EDM_DRO@y..., "awallin25" <anders.wallin@h...> wrote:
> > 
> > > Also I'm wiring up home switches.  I plan on using the encoder >
> > index
> > > pulse and a micro switch. Both will be inputed to a 74LS00 IC.
> > > Question is, Can I wire direct or do I need a resistor for the
> > encoder
> > > index. Three gates are used, X,Y, and Z. But EMC only needs one
> > input
> > > ,... can I tie the three gate's output together?
> > 
> > you would probably consider one axis homed when both the home switch
> > is on AND you get an index signal from the encoder.
> > But you need to tell EMC when any axis is at home, so i guess the
> > solution would be:
> > AND together the home switch and encoder index for each axis.
> > OR together the results and wire the result to the EMC home input.
> > 
> > EMC users: can you tell me how EMC does "homing" ? I would guess
>
> this
>
> > has to be done one axis at a time ?
>
> You don't tell EMC when an axis is at home rather the switch does.
> When you select "home" for an axis "that" axis moves toward the
> switch, trips it then moves back a set distance. Because of this the
> switches are parallel. Just didn't know if I could parallel the gates
> output.
>  
> Frank