Re: Opto / relay recommendation

Thanks Steve,

So if I'm wiring up one of these anyway, is it worth putting all of
the parallel port I/O pins that I'm using through a ULN2003 ? Would
it be ok handling step/direction signals ? Is there a practical limit
to the frequency of step/direction signals it can handle ?
Would it help to protect the parallel port on the computer ?

Thanks again,

Rab

>
> Couldn't be easier with a ULN2003 - pins 1-7 connect to a parallel
> port pins or TTL signal or whatever, Pin 8 is ground, Pin 9 is Input
> Power , Pins 10-16 are the outputs.
>
> eg - +12V to pin 9, connect Pin1 to parallel port, say pin 11,

apply a

> signal to // port pin 11 and you get +12V at ULN Pin16. Remove the
> signal and Pin16 switches off. Great for driving relays for spindle,
> coolant etc.
>
>
> Steve Blackmore
> --
> Pilot Consultancy Limited ***** Computer Consultants
> Telephone 01744 752256 Mobile 07831 768478
> Email: steve@p... WWW: http://www.pilotltd.net