Controlling a Lamp Circuit

[TomGibbons]

So I have a simple circuit - just a lamp and a battery. I want to put something inbetween said lamp and battery that will connect to my pc (LPT/COM) so I can switch it on and off via my C# application.

Do any libraries exist for communicating with such devices? And I've never made anything to interface with a computer, so does anyone have any idea how to do the electronics part of it?

I've searched the forum for COM and LPT connections and come accross a load of VB6 stuff and people go on about creating a driver circuit.... can anyone help?

Thanks,
-Tom

[Mike Hildner]

Apologies I can't help, but once I had a request to be able to open a security gate from my program. I started to look into it, but then the client dropped the idea. I had no idea where to start so I talked to a electronics geek at Radio Shack. He started pulling out stuff that I could plug into a COM port (IIRC) that would do that. Of course .NET has no classes yet for serial communications.

Edit: Looks like you're from the UK. Not sure if they have Radio Shack stores there, but in the US, they're all over the place and generally, the people that work there are serious electronics geeks.

[wossname]

Originally posted by Mike Hildner
Apologies I can't help, but once I had a request to be able to open a security gate from my program. I started to look into it, but then the client dropped the idea. I had no idea where to start so I talked to a electronics geek at Radio Shack. He started pulling out stuff that I could plug into a COM port (IIRC) that would do that. Of course .NET has no classes yet for serial communications.

Edit: Looks like you're from the UK. Not sure if they have Radio Shack stores there, but in the US, they're all over the place and generally, the people that work there are serious electronics geeks.

The nearest thing to radio shack we have is Maplin, there should be one near you Tom.

I once soldered up an LTP port blinker (8 LEDs and a few resistors in parallel plugged into a pass thru lpt cable. It could easily be adapted to supply a small current across up to 8 transistors and thus power any device you like from stepper motors to lightbulbs. Supplying a byte to the LPT sets the 8 LEDs to display the binary of that number, say sending the number 29 (00011101 in binary) as a byte will display @@@@@@@@

Google for "LPT LED circuit" and you should dig up a suitably adaptable circuit. I'm available for PCB engraving commissions if you need one thrown together.

[TomGibbons]

Oh okay thank you both.

Wossname: That's great. I'll start looking in to that. I may well contact you again soon :)

[john tindell]

take a look at

I/O Ports Uncensored - 1 - Controlling LEDs (Light Emiting Diodes) with Parallel Port
http://www.codeproject.com/csharp/cspplcds.asp

I/O Ports Uncensored Part 2 - Controlling LCDs (Liquid Crystal Displays) and VFDs (Vacuum Fluorescent Displays) with Parallel Port
http://www.codeproject.com/csharp/cspplcds.asp

been reading though them, havent tried them, but thats becuase im skint at the moment