Bruce wrote:
> One for the PC gurus I suspect, but is there a bus signal on a PC bus one
> can intercept/control that will disable/enable video output to a monitor?
>
> I have an existing device, using an LF initiator coil, that enables the AFE of a 
> PIC16F639 in an ID badge worn by the user. The LF data from the initiator sends
> an 8-bit challenge code to the PIC16F639, wakes up the controller, which then
> transmits via UHF (if the challenge code matches) to a receiver that makes or
> breaks a video signal (hardware connection between video card & monitor) using
> a small DIP relay.
>
> This works fine, but I would prefer to build a card with the receiver that inserts
> directly into a PC card slot VS the mechanical relay option.
>
> Is this do-able?
>
> Regards,
>
> -Bruce
>
>
>   
Not easily (read, practically impossible).
Best bet is probably to make a little serial/usb module then use a tiny 
program on the PC itself to just trigger the screen saver or something 
similar.
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