Hi.
I'm working on an idea of having my USB HDD start with a 15-20 sec delay.
This is due to some boot problems with my WD external hdd. The problem is that the computer freezes during boot because it tries to boot from the external hdd, but there is no OS on that drive.

My idea is that when the computer is powered on i will have a delay-curcuit hijacked in on the power cable from the USB and using a analog switch to start a delay-curcuit that controlls a rele that switches the data connection in the usb from off to on.
I have tried to make a simulation of the idea, but i'm not shure that it will work even thou it seems good in the simulation.

I was hoping some of you here could give me som input on improvements, heat problems, and other things i might (or most likely) havent thought of.

 

Is your BIOS set for correct boot device?

What motherboard are you using?

 

It might be better to configure the BIOS not to boot from a USB device, especially if your primary hard drive is having problems coming up. That is where I would devote my attention. That primary hard drive is going to fail sooner rather than later. Are you sure you understand the USB protocol well enough to know that this scheme will work?

 

There is a huge problem with some seagate and wd disks, and i could switch the legacy mode, but i dont have sp2 input, so if i need in to setup i cant use the usb keyboard. So i need the delay circuit. I'm on a samsung ssb-a computer

I have allso tried to disable usb boot, but with no result.

The usb protocol is not a huge problem. I've played around with it earlyer, but not like this.

 

Hi paulktreg. Here is the data for the motherboard.

 

Is there anyone that could take a look at the circuit and tell me if this is possible to make, and if it is going to work?