how should I hook up my windows circuit to the alarm system?

[david90]

best way to do this?

When I unarm my car alarm system, I want my windows to roll down. I got the windows-roll down circuit all figured out and it requires a momentary logic 0.

So how should I hook up my windows circuit to the alarm system?

 

[Externet]

Re: best way to do this?

Look for a node in the alarm circuitry that becomes 0 when gets disarmed. If you only need a momentary 0 to lower the windows, linking the node to the windows activation with a capacitor of the proper value will produce a momentary 0.
Miguel

 

[david90]

best way to do this?

What if I want the system to only roll down the windows only when active unarm, passive arm, and then active arm button is pressed? I don't want to roll the windows down everytime I unarm my car. Only when a certain arming and unarming order is pressed.

Finite state machine is the solution?