Need schematic made

thedog300 · 09-08-2007, 01:13 PM

I am trying to design a circuit that switches to my rear view camera when I go into reverse, at first I thought of the laptop power on switch and connect it to my lilliput k301 av switch, and connect it to my reverse lights, and that should switch it to video 1 from vga mode, then I want it to go back to vga mode when I get out of reverse, I'm thinking a spst relay for that, the problem is I need the circuit to "push the av button" twice? if someone could make a circuit for that, that'd be really helpful, thanks.

dupa2 · 09-08-2007, 10:45 PM

Oh my got! This is most crazy plan I ever heard of. Why don't you just use usb camera, connect it to the computer, make very simple interface to sense reverse gear, and pass it to the computer (let's say through parallel port), then write quick app to dispaly the view.... I'm kidding, it's rather job for software developper. But it would be right way to handle it.

Anyway, you'll probably need rising/falling edge detector that could drive your screen VGA/AV button. Try to find flip-flop of JK type circuit, or some kind of logic state change detector. These have typically 5V or 3.3V logic signals on outputs, and I believe your monitor button basically switches the function upon shorting AV/VGA signal to ground. So this should work just fine.

2k1Toaster · 09-08-2007, 11:22 PM

Quote: Originally Posted by thedog300

I am trying to design a circuit that switches to my rear view camera when I go into reverse, at first I thought of the laptop power on switch and connect it to my lilliput k301 av switch, and connect it to my reverse lights, and that should switch it to video 1 from vga mode, then I want it to go back to vga mode when I get out of reverse, I'm thinking a spst relay for that, the problem is I need the circuit to "push the av button" twice? if someone could make a circuit for that, that'd be really helpful, thanks.

There is already a circuit for this in the forum. For this exact purpose. It sends pulses to the AV switch button on reverse and then sends more pulses when reverse sense goes away.

thedog300 · 09-08-2007, 11:26 PM

I do have afew webcams lying around, I may replace the lenses for wider viewing angles and nightshot, but i'm a bit comfused about how to get the interface to work. I've only done input commands with turing, but I could easily throw some code together in java, c++ or basic and jsut run it in the background, what I'm not sure on how to do, is how to get the interface to "detect" the reverse lights are on. I guess I could splice the wire and throw enough resistors on one end until I get about 5 volts to go to the parallel port. Also another problem with this plan , is my laptop doesn't have a parallel port, so I guess I'll need a solution in usb, and I don't really feel like spending 50$ on fusion brain for something as simple as this

inh · 09-08-2007, 11:27 PM

I just use a camera and some software...

edit: http://www.mp3car.com/vbulletin/lcd-...-lilliput.html

thedog300 · 09-08-2007, 11:47 PM

wow, a bit more complex then what I thought it would take, I'm up for a challenge though. Thanks guys.

2k1Toaster · 09-08-2007, 11:49 PM

Quote: Originally Posted by inh

I just use a camera and some software...

edit: http://www.mp3car.com/vbulletin/lcd-...-lilliput.html

Yup that's what I was thinking of, but I couldn't find it.

inh · 09-08-2007, 11:54 PM

I plan on hookin in to my reverse switch and then running a wire to one (of my probably many) fusion brains and having it switch to my reverse camera program automagically. as soon as the com interface is done of course