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Electronics Combination Lock ;)

Discussion in 'Modding' started by SteakTheMooCow, 5 Apr 2006.

  1. Tulatin

    Tulatin The Froggy Poster

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    It's a 9 digit code right? That means, at least you'll need 9 inputs, maybe less if it's repeating. After all, do they need to know that the other keys aren't functional? ;). You can still make them push in, and light up with the grid, right?
     
  2. monkeyville

    monkeyville Evilish Monkey ++;

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    I'd recommend something from Microchip to power your circuit. Its incredibly easy to code (as long as you know c) and the IDE and chips are free as long as you dont need any more than the "trial" amount they send you.
     
  3. Davidbrent

    Davidbrent What's a Dremel?

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    Why on earth would you power this circuit with two AA batteries, when there is a 5 volt line that is on as long as the power supply is plugged in. Do you know what you are talking about or are you just pretending? I would suggest using the PIC you will have to learn a bit about them and build or buy an programmer but its worth it although if you want a simple solution you can always use the PICAXE. Also take no note of people suggesting you multiplex the inputs there should be no need. You could have the nine buttons that make up the code attached to seperate inputs and have the remaing 30 connected in parallel to the same input. This way you could get the program fail if any one of the 30 buttons is pressed and loop to the beginning. As Albert Einstein said himself: Keep everything as simple as possible but not simpler.
     
    Last edited: 10 Apr 2006
  4. Stuey

    Stuey You will be defenestrated!

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    *rolls eyes*. It was a suggestion made according to my preference. I didn't state or even imply that it's the only way, just another way.

    He doesn't want the program/circuit to automatically reset if the wrong buttons are pressed. Or at least I assume that's his mindset. The way it works in the show, 7 symbols are pressed and a stargate is activated if the permutation is valid. If the permutation is not a valid address, a wormhole is not engaged. Assuming the moocow wanted to adhere to this, every pressed button would have to light up, but an incorrect combination would not boot the system.

    Do you know what YOU'RE talking about, or are you pretending...
     
  5. AJB2K3

    AJB2K3 What's a Dremel?

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    Someone else once said
     
  6. Davidbrent

    Davidbrent What's a Dremel?

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    Well to supply power to the curcuit this way would mean that every so often you would have to change the batteries. This is more expensive and less practical as using the 5 volt standby line.

    I am not a Stargate fan I assumed he wanted a keypad lock system. My advice on not to use the multiplexing of inputs idea was still relevent as you can still use it for the Stargate system. I suggested it to make it a simpler curcuit to design and build.
     
  7. Stuey

    Stuey You will be defenestrated!

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    While I admit that his initial post isn't too informative about his exact intentions, his mention of his intent to build a DHD power on device is where I got my assumptions.

    I suppose you are right in your suggestion to use the 5V rail. I still believe that AA batteries *could* be an acceptable alternative since they could last a pretty long time in usages like this, but it may not be the best idea, as you pointed out.

    Hmm... working off your idea to use the 5V standby cable, how would this (if at all) affect the power distribution once the system was booted?
     
  8. Tulatin

    Tulatin The Froggy Poster

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    Who says he has to change batteries? They can be rechargable ;)
     
  9. Davidbrent

    Davidbrent What's a Dremel?

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    The 5 volt standby line is still live when the computer is powered up. Using the 5 volt standby line is the best idea in theory however if the person building this project does not want to start cutting up their power supply wires then yes using a couple of 1.5v batteries would work perfectly fine.
     
  10. g0th

    g0th What's a Dremel?

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    A convenient way to get access to the +5V standby rail, if you don't want to just solder a wire on to the back part of the ATX connector pin, which is neat and easy, is to plug on to the WOL/WOM header if your motherboard has this. This header has the auxillary +5V rail on it.
     
  11. Davidbrent

    Davidbrent What's a Dremel?

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    Good point. I don't know what I was thinking when I suggested cutting the 5v standby line.
     
  12. SteakTheMooCow

    SteakTheMooCow What's a Dremel?

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    Goth has the advantage of having spoken to me on OCAU and GoogleTalk :)

    Yeah, I'd probably use the WOL/WOM header on the board to give the power. AA's aren't exactly a great plan, so yeah, that was it... as for programming a reset, I misread that ;) Initially I thought "I don't want the code to work as a reset button."

    Although, on second thoughts, the answer is "yes" to both sorts of reset ;) A different code (Abydos perhaps?) for a reset function that emulates holding the power on for 5 seconds...
     
  13. Halgy3000

    Halgy3000 What's a Dremel?

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    I don't know if you have a reason for a 9 digit code, but the Stargate has the 7 coordinates and the activator, 8 digits not 9.

    PEACE
     
  14. John_Edward

    John_Edward What's a Dremel?

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    6 symbols + point of origin + galaxy + one unused
    Thats 9 right ?
    If i remember right :p
     
  15. Halgy3000

    Halgy3000 What's a Dremel?

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    Oh, he is just gunna use all 9 chevron points. I thought his code would be like an address for a planet. My bad.

    PEACE
     
  16. Halgy3000

    Halgy3000 What's a Dremel?

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  17. SteakTheMooCow

    SteakTheMooCow What's a Dremel?

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    First 7 are a planet. Next two are my initials + a number to throw it off (1-39 loopbacking back to 1 at 40...)
     
  18. Callum

    Callum What's a Dremel?

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    I'm no techie or great modder or anything, but that seems a baaad idea. Security wise, if you have 39 buttons, there are 39^9 combinations possible (or 39! without repeats). If 30 of these buttons reset the circuit, then it is simple enough to figure out which 9 work. Leaving only 9^9 or 9! combinations...

    Although after typing this... It's a circuit to stop someone turning a computer on. If someone wanted to turn the computer on without permission, it would be a hell of a lot easier to simply disconnect the circuit than try all of 9! combinations :p

    Never mind ;)
     
  19. g0th

    g0th What's a Dremel?

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    It's plausible enough to make the circuit tamper resistant if you were really concerned about it.

    It's more for show / 1337 mod effect then as a security thing the way i see it.

    Anyway, 362880 combinations is a lot to try.
     
  20. Halgy3000

    Halgy3000 What's a Dremel?

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    Ok, kool. Sorry if I seemed like an a**. You now have me thinking of doing a combination lock for my mod. Locks rule. DHDs rule harder.

    PEACE
     

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