I pray that you never get a job working at a missile silo... "hmm, a red switch...why do I have an uncontrollable urge to flick it..." *5 mins later* "Mr President, we have an unauthorised nuclear launch!" *sirens going off in the distant...*
all right - i sat down and tried to think this whole thing over again. so far the two best options are: 1) relays - i'm not too good with them so i'd need help on that (ConKbot of Doom, were you going to draw up a schematic still? if not, no worries - just curious) 2) DPDT keyswitch. i can't see any reason why this wouldn't work? anything i'm missing about problems that occur?
dpdt should be fine but i thought you couldn t find one of those. the advantage of the relay is that if it has enough contact groups, even with an additional relay, you can wire them so that you can t turn it off while the pc is on, or you can do something like take the key out while the pc is running and if somebody shuts it off it won t start up again without the key...
I have the schematic, but uploadit is being a PITA. Edit: Edit 2: uploadit is still not working right.
Forgive me for being inexperienced in electronics, but cant you achieve this if you had a keyable switch either open or close the +12 and +5vdc lines? Like switch off, 12 and 5v lines are open. No power to hard drive and it will not power on. Switch on with key, 12/5v lines are closed and hdd powers on. bacon: I've emailed a removable rack company, maybe they'll help me out. ppsst I'm on irc as RR5.
Bacon, as nobody else seemed to notice this, the key in the switch is removable only in the off position, witch means of corse, that either when the hdd's are enabled, you can't remove the switch (bad, because one slip and "oops, just killed your computer, sorry!") or it means if you switch it so that the key can only be removed while the hdd's are enabled (it's a Double Pole Double Throw after all) and defeats your entire plan all together.
There ya go, that would very good solution right there, have a bolt lock mounted on a drive bay cover or something, then have the door either swing out of the way, or come off to reveil two small toggle switches (like those "rocket launcher" switches). Up for off, then down for on (so that the cover comes down and they are officaly "on").
thanks for the info guys. right now i'm still leaning towards maybe getting some relays hooked up, but i haven't decided yet. and Malfoleo, i noticed it was only removable in the off position right before i ordered i'll post when/if i ever get anything working!
How about going high tech and placing the switches in the psu. It could be like James Bond stuff. You press a remote control, the panel on the psu slides up, revealing some sexy switches! You flip one, and power the computer on with no problems!.. Later, aw man you have to go save the world, so you activate that remote control and flip that same switch. Now the 12v and 5v lines are "open" and no power is being sent to the hd. Joking and humor aside: Mount a tiny switch inside the psu. Then make a door for it so you can open it.
lol /me hums james bond theme song but really - i don't think i could do that cause 1: i wouldn't be able to make it look pretty and 2: i'm going to be limited on space (this is going to be part of a shuttle system)
All joking aside, I feel you could pull this off with switches. I'm no artist, so I'll get boring with descriptions. A switch will either open or close a circuit. In this case, we want to open or close the power lines on a molex to a hard drive. (or drives) so it will either work or not work. A nice 2amp rated switch should function exactly as you like it, providing you use the switch with the power off.
askpcguy, i definetly agree a switch would be the easiest/cheapest/whatever way to get it done, but i need someway to make sure it doesn't accidently get flipped while the HD's are powered on (hence the desire for a keyswitch). like i said, i'm still thinking of ideas, and i'll probably actually build a few things (one with relays, one with just simple switches like you said, etc.) and then see which one will work best for me...
Why not simply use a boot manager? I use Select-It from Quarterdeck since many years (unfortunately it isn't not sold anymore, but I'm sure other actual boot managers can do the same). It permits you to create several boot entries, ex. for different OS'es, AND hide partitions and/or disks for specific boot entries. No hardware needed... Disks are powered all the way but simply not visible/accessible. Just my 0.02 cents (in dollars or Euro's ) CD
Software is all fine and dandy But may I point out that a secure hardware switch would be about a thousend times cooler? And a lot more "elite" ? Just my two pence though.
