Need Help with sequenced switches

[jaymolt]

I am trying to design a circuit with two switches that must be closed in one specific order only to complete the circuit. Example: Circuit will only complete if switch A is closed before switch B. If switch B is closed first and then switch A is closed, circuit will not be completed. In such case, the circuit must be reset by opening switch B before switch A then B can be sequentially closed to successfully complete the circuit. Can anyone give me some guidance on how this might be done. The project uses 12vDC power.

 

[jaymolt]

Can this be accomplished with a 555 timer IC?

 

[(*steve*)]

probably easier with a microcontroller

 

[CocaCola]

probably easier with a microcontroller

Dead simple with a micro...

 

[jaymolt]

Thanks for the direction. I am a newbie but learning fast. After all is said and done, a micro would actually make several aspects of this project cleaner. I was trying to avoid taking this step but in the end it will be a better mousetrap. Any suggestions? Arduino?

 

[CocaCola]

Any suggestions? Arduino?

Long term or short term?

If you are for the long run, you should really learn assembly as well as c and c++ as this will allow you to jump across platforms and already have a good grasp of the entire process... And with that you should go for the 'raw' chips and not the DIY kits out there, as you really need or should also learn how to build the circuit vs plugging something it...

The Arduino, Basic Stamp (outdated but still very popular in education circles) or Picaxe are good for quick and dirty work but I cringe every single time I hear Arduino this or Arduino that, everyone seems to think it's the end all monkey wrench of electronics... 9 out of 10 times a $1 mirco and another $1 worth of supporting components will accomplish what many wastefully use a $30 or $60 Arduino for...

In the end what are you future plans? The Arduino makes a great entry level option (as you get the IDE and programmer all in one) but please if you want to stick with it learn that it's nothing more than an Atmel AVR with a bootloader and learn how to expand beyond it and into your own designs based on the raw chips and support components vs plugging in a module or wire here or there...

 

[jaymolt]

Thanks for your thoughtful reply. I suppose I was looking for an easy fix but as you pointed out, if one is "in for the long haul", it really is more about the journey than the destination.