Still confused on DC/DC, Shutdown controllers, and STR... couple Qs please.

**pooshda** · 02-21-2003, 10:56 AM

Ok I have been reading on here about shutdown controllers, DC>DC power supplies etc... I know exactly what I want my car/pc to do so I figured I would mention it on here and see what you all think would be my best options... because this is still a little confusing to me as I have never put a pc in a car, and I dont want to do it "half ***"

First of all, I am looking at the 250watt Keypower DC>DC PSU... My pc will basically consist of a 1ghz AMD, 256mb mem (or 512), GeForce2 GTS 64mb, SbLive, SCSI adapter/Plextor SCSI burner, 80 or 120gb HD, etc... basically close to the limit of the PSU, I know it will be enough though because I run 5hds on a 300watt w/ AMD and all that stuff inside plus a 2nd burner...

This is what I want!

I want a shutdown controller that will NOT shut down the pc, I need something that will trigger STR (suspend to ram), I read up on these shutdown controllers and I never see any specific stuff about STR or making it work with them... I know people do it but I havent seen its specifically explained EXACTLY how to do it automatically... I want my car to STR when the ignition is off, I want it to stay "on, but suspended" THE WHOLE TIME until I start the car (unless I power it off manually)... I dont want to have it boot up everytime the car comes on!

Most of these Shutdown controllers seem to have some 20 minute window or something where (by how im reading it) it will shut down no matter what after that point, I dont want that I want it to suspend... am I just confused here or what?

tell me EXACTLY what I should buy to get it to do exactly what I want it to do, because im not getting anywhere on my own really... I just want my pc to come back to life... same applications open, same mp3 playing, in under 10 seconds from when the car starts... less if possible.

Thanks a lot, sorry about the long message I really appreciate the help though.

**Charliey** · 02-21-2003, 04:10 PM

Does your motherboard have a STR button header? (So that you can push a button and trigger str from a button outside, not inside windows)

if it does, then you just need a timer that will connect the header for a short period of time when the acc line goes off, and reconnect it when it comes back on.

in my searching around, i found this circuit that will do what you want (at least it says it will, i havent built it yet):
http://www.astron.nl/~smirnov/poweroff.html

instead of connecting it to your power button, you connect it to the STR button header.

**zootjeff** · 02-21-2003, 04:51 PM

STR will kill your battery if you don't use your car all weekend. If you have a beefy battery you may have a week. Some people might not even have more than a day.

**t0ffluss** · 02-21-2003, 05:35 PM

Im using STR, 1 week and 2 days are the longest interval i'we had my carputer in STR, battery still going strong.

My battery is not of the beefy kind, (50Ah)

EVERYONE ALWAYS TALKING ABOUT A COUPLE OF DAYS ?!

iwe measured it to 0.09A ... that will NOT kill you battery in a weekend, or a day...

Use STR, its the best thing you'll ever do to you carputer. You have no idea how great it is to have music playing within 8 sec's...

Richard

**pooshda** · 02-21-2003, 07:39 PM

Thanks guys! I really appreciate the information, if anyone else has other information that would be helpful please dont hesistate to reply... I think my motherboard triggers STR through software somehow, not through the power button though... does anyone have a recommendation for an AMD socket a motherboard (duron, athlon tbird...) which will have this?

Im going to need to buy a new motherboard anyway, doesnt matter how large it is and I dont really need onboard audio or anything UNLESS ITS VERY GOOD QUALITY... then ****, might as well save myself the need for a sound card... onboard scsi might be nice too, because my burners are both scsi...

And about STR draining the batter, it wont be an issue... I drive my Supra daily in the summer and if I dont plan on driving it for a few days, I can simply just shut the pc down entirely

Thanks again..

**Whaleboy** · 02-22-2003, 01:24 AM

On my setup, I'm using STR(3), such as what you're talking about. The problem I had, was getting something to simulate a power button press whenever the car came off/on so I could get it to go on suspend.

I built the following circuit for it:

http://groups.yahoo.com/group/dashpc...%20circuit.jpg

It's by Micheal Carr that hangs out on the dashpc groups there at yahoo. You may have to subscribe to the group in order to see that file.

The circuit works great. Whenever I turn my car on or off, the circuit detects the voltage from the 12v accessory line, and simply simulates a power button press to the motherboard. Car comes on, power pulse goes to the button headers on the motherboard. car turns off, another power pulse to the headers.

I use an EPIA 800 MB, and WindowsXP - XP is set up to go on standby whenever it see's the power button is pressed.

The result, 8 second boot time.

Mind you, this is only beneficial if you're using a DC-DC powersupply(of course). Powerdraw from the motherboard is around 700milliamps (eq. to powerdraw from your car radio for keeping it's presets stored).

I've gone a little less then a week without driving the car while the computer was in suspend the whole time, started up just fine. The battery still has a completely healthy charge.

You could easily buy a battery protector circuit that would automatically detect when the battery has drained to the point of no return and cut off the 12v line to the computer. But as it's obvious as several people here use STR - powerdrain isnt an issue.

It doesn't have any type of time delay, but you could easily add one to this circuit by just doing a search - there's been posted a few seperate circuits for simply just producing a time delay.

**t0ffluss** · 02-22-2003, 05:01 AM

oooooor,

getting an opus..

fixes everything

delays, simulated power off..

Richard

**Whaleboy** · 02-22-2003, 07:09 AM

I was under the impression the opus completely removes power from the system on shutdown?

Is it capable of not only sending the machine into STR. But also doesn't completely remove the power from the motherboard after it has done so?

Just from my brief glimpse at the Opus that was the impression I had of it, but I may be wrong.

No power after STR doesn't make it STR anymore.