Looking for a creative solution: USB bus still powered after CPU is off - Page 7

archimense · 08-23-2004, 03:39 AM

Quote: Originally Posted by rando

Yes, that's correct. Here's a schematic.

I just did this mod to my OPUS 150 and I can confirm that it works as described with my EPIA M10000.

Thanks again for the help Rando.

rando · 08-23-2004, 09:27 AM

Quote: Originally Posted by archimense

I just did this mod to my OPUS 150 and I can confirm that it works as described with my EPIA M10000.

Thanks again for the help Rando.

N/P. BTW, you didn't actually mod anything on your Opus, right? I just bought an ATX cable extension and did my splicing there.

Ricky327 · 08-23-2004, 10:01 AM

Rando,

Just out of interest...from what I suggested earlier on the thread was it really neccessary to have the delay between the ACC and trigger for the OPUS to work reliably?

Im sure you mentioned somewhere that a delay may be needed from the result of your testing, or was it fine as it is?

rando · 08-23-2004, 10:19 AM

Quote: Originally Posted by Ricky327

Rando,

Just out of interest...from what I suggested earlier on the thread was it really neccessary to have the delay between the ACC and trigger for the OPUS to work reliably?

Im sure you mentioned somewhere that a delay may be needed from the result of your testing, or was it fine as it is?

Yes, I did confirm that the Opus intermittently failed to startup the computer when ACC is energized before the +12V input. See post #64 and your acknowledgement in post #65.

Ricky327 · 08-23-2004, 10:26 AM

Ah ok...I did remembered it being mentioned, sorry I cant be bothered to read all the thread again...its too long.

Just made me wonder as I cant see any delay circuit on the schematic you posted...so I kinda assumed the delay was not needed.

Those guys following your circuit may have reliabilty problems?

or did I get it all confused now?

savante · 08-23-2004, 10:33 AM

Ricky327,
Doing it the original way, using relays to drive the opus power would require a delay to give the +12V to the Opus before the ACC.

The schematic is just using the relays to drive the PSON and +5VSB from between the Opus and the motherboard... which is not the way originally described.

Does that help?

Ricky327 · 08-23-2004, 10:36 AM

Ah ok, thanks for the clarifications

I should have followed the thread all the way...oh well.

I think I better stay away from the thread as Im way out of line now

Good luck

rando · 08-23-2004, 10:55 AM

@Ricky: It's a different solution.
@savante: Correct!
@Ricky: LOL, you're welcome here...everyone has a bad day now and then.

archimense · 08-23-2004, 12:54 PM

Quote: Originally Posted by rando

N/P. BTW, you didn't actually mod anything on your Opus, right? I just bought an ATX cable extension and did my splicing there.

Correct. I didn't mod the power supply itself, just the ATX cable from the OPUS to the motherboard.

djkriz · 08-24-2004, 05:05 PM

since I am no electronics expert, i've got a question about the schematic by Rando.

Is it important which ground I take for the relay?
Since it uses two +12v inputs, 1 from the ACC and one from the +12v of the opus, can I take any of the black wires used in the ATX connector or just ground it directly on the car? Or doesn't it matter?

thanks!

savante · 08-24-2004, 05:18 PM

Ive thought about this myself. I think if you ground it to your car you would be ok. I would try to ground it to the same point you are grounding your opus...
I think at that point you would have common ground, which would basically be the same as connecting it to one of the black molex wires. I could be wrong though....
Just my thoughts.

archimense · 08-24-2004, 05:49 PM

I don't think the ground should matter. For convienence though I used the ground wire in the ATX power cable, because I was already running wires there for the +12v from the OPUS.

brage · 08-24-2004, 10:18 PM

Quote: Originally Posted by rando

Yes, that's correct. Here's a schematic.

thanks rando! I implemented your schematic and it works like a charm

rando · 08-25-2004, 12:22 AM

The diagram is just a schematic. It doesn't tell you how/where to grab your power sources or grounds. There are MANY other posts on this site and elsewhere around the web that discuss proper power distribution and grounding techniques. In the case of the relay just use whatever ground source is most convenient -- but make sure it is a good ground. Your systems common ground point, battery negative terminal, or a ground from one of your 4-pin molex connectors are all good choices.

@brage: Cool, I'm glad it worked for someone else.

Jackboot · 08-31-2004, 01:38 AM

2 Questions from an electronics n00b:

1. Must I do this mod or my battery will die? Or can my battery tolerate this type of drain overnight on a regular basis?
2. I don't know how to read a schematic. Any help or links on schematics / relays etc available that can help me decifer what I need to do?