Crude but hard to get simpler than a USB controlled plug strip:
  http://www.instructables.com/id/A_USB_Power_Controled_Plug_Strip_With_Isolation/


-----Original Message-----
>From: "David Duffy (AVD)" <david@audiovisualdevices.com.au>
>Sent: Jun 12, 2009 2:47 AM
>To: "Microcontroller discussion list - Public." <piclist@mit.edu>
>Subject: [EE] USB to contact closure
>
>I have an application where a PC needs to trigger another device via a
>contact closure. The current PCs have serial, parallel and USB ports
>available, but in future one may only have USB.
>
>My first thought was an FT232 USB-serial chip and a small micro driving
>a reed relay, but I'm trying to simplify the design and get the cost
>down as there's potentially 1000 or so units to deploy.
>
>I've never delved into "USB on a PIC" so don't know how easy it is. Also
>bear in mind I have no C language experience.
>
>My other thought was to keep the FT232 and ditch the PIC, simply using
>one of the serial control lines to trigger the relay.
>
>The consequence of erroneously activating the relay during PC powering
>up is not too much of a problem. (I have to confirm this)
>
>Does anyone else have any ideas?
>David...
>
>-- 
>___________________________________________
>David Duffy        Audio Visual Devices P/L
>Unit 8, 10 Hook St, Capalaba 4157 Australia
>Ph: +61 7 38235717      Fax: +61 7 38234717
>Our Web Site: www.audiovisualdevices.com.au
>___________________________________________
>
>-- 
>http://www.piclist.com PIC/SX FAQ & list archive
>View/change your membership options at
>http://mailman.mit.edu/mailman/listinfo/piclist



-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist