what is the easist way delay my switch 12v for 2 seconds???

bertybassett · 04-23-2005, 05:52 PM

I need this so my carputer can survive cracking. For about a year my carputer would boot fine, then of late I noticed it would not boot correctly every time. It would sometimes reset while coming out of standy by cuasing a full reboot of the system instead of returning from stand-by.

To fix this problem I changed the power supply from a Carntix P1260 to a M1-ITX and still I was having no joy. I've re-wired the whole issue still no success. Now I'm thinking that the battery might need replacing but the cost of a deep cycle battery is well over £175 so before I shell out that much cash I want to try everything else. I was thinking of adding a 2 seconds delay on the ignition wire, which might help. Do'es anyone have any ideas on how best to go about achieving this?

Cris · 04-23-2005, 05:54 PM

Well, do a search on Jeff Mucha's controller...or get an Opus

.

bertybassett · 04-23-2005, 06:01 PM

why oh why must everyone mention opus when I say I'm having power problems with cracking. The carnetix should work to >7.5v and the M1-itx about the same so both should survive cracking as the OPUS only goes that low too.. It not the type of power supply I'm using that is causing the problems. Its something about the setup or power coming from the battery.

bertybassett · 04-23-2005, 06:02 PM

BTW way would I want a Jeff Much SDC, when both my unit's already have SDC in them. I just want to delay them from coming on for 2 seconds to see what differance that makes.

Change · 04-23-2005, 06:58 PM

How big is the power cable you're running to the PC? Is it hooked straight to the battery (with an inline fuse)?

I believe the Carnetix controllers allow you to flash them with your own timing modifications... http://www.carnetix.com/firmware/uflash.htm
Ask around in the Carnetix forums for more.

shakes · 04-23-2005, 11:13 PM

it sounds to me like maybe you haven't really located the heart of your issue. You're right, your 1260 should survive a crank easy.

Have you placed a voltmeter on the feed from the batter while cranking to see if it dips below 7.5v?

also place the meter on the main 12v feed after your 1260 ... does it ever cut out during cranking? it shouldn't.

What happens once the car is started if you shutdown and reboot (to simulate what happens when the car is started) ... or place it in standby (or hibernate) while the car is running and then turn on the PC again.

Are you doing standby or hibernate? if standby see if hibernate works better. If hibernate ... it's very possible there could be some corruption with your hibernate swap file.

mushin · 04-24-2005, 12:57 AM

I'm surprised no one has addressed the actual question. Berty, check out some delay circuits here.

shakes · 04-24-2005, 01:08 AM

I don't think anyone's addressed the question because based no what he's said, it sounds like a delay circuit shouldn't be needed.

It seems to me like implimenting a delay circuit at this point would be treating the symptoms and not the problem.

RoyN · 04-24-2005, 03:02 AM

I'd say try implemnting what is known in the technical world as a Manual Delay Circuit...

it is very difficult to explain but I will try... Stick a switch between whatever you want to delay, and then crank the car, wait X seconds (this is programmable!) and flip the switch...

there you have your delay....

Just to loosend the tension, and if you are just trying to test out, I think it would be simpler to add the switch before going out nd makign a delay circuit just for this test...

bertybassett · 04-24-2005, 05:50 AM

yeah thanx for the top idea of a switch.

bertybassett · 04-24-2005, 09:15 AM

@ Change yeah the power cable is maplin speaker cable. it should be more than enough for powering the carnetix or M1-ATX. The size of the cable is bigger than the wires supplied with the carnetix or M1-ITX.

@ Shakes I'll try measuring the voltage when cranking and see if the computer drops 7.5v. Tried hibernate and stand by and they both reset.

BTW the ignition wire is taped off the stereo ignition sire would that make any difference? Should I take a wire direct from the ignition it's self?

Off to do some testing and I'll let you all know the results.

bertybassett · 04-24-2005, 09:37 AM

I'm getting a full 10.5v under cranking so can't be a battery problem. Might be the car computer not coming out of stand by correctly. I'm going to remove the carputer and test in the home to see if it a software problem.

After that it is a delay switch for testing.

bertybassett · 04-24-2005, 09:41 AM

Just thought I'm only getting the problem after the computer computer has been left in standby for more that 4 hours. So I leave the carputer in stand by for 4 hours and test the voltage again and see what happens.

Bugbyte · 04-24-2005, 09:48 AM

It does sound like it's an issue with the computer, not the power supply. Try the 4 hour thing in the car, then try it in the house with power from the wall socket. If there's no difference, it's got to be something with the PC.

bertybassett · 04-24-2005, 10:18 AM

yeah I'm starting to supect the PC or software more and more now. Going out to car to remove it as we speak. hopefully have some results in a few hours.