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[on:]

i am try to connect the electric door strike to Arduino and i d'ont know how to start.

how i connect him?

what the code to open and close?

this what i have :


alot of tnx!

[Reply #1 on:]

i d'ont know how to start.

Find the spec for the door strike. Understand what the electrical characteristics are. Design a circuit capable of driving the electrics which can be controlled by TTL levels. Build that circuit and connect it to the Arduino. Write a sketch that provides the appropriate TTL output signals to make your driver circuit operate the device. Design the rest of the sketch to implement whatever control algorithm you want. Presumably you'll have some form of inputs to determine when to operate the door strike; you'll need to carry out a similar exercise to interface the Arduino with those.

[Reply #2 on:]

this what i do, what wrong?

the transistor is 2N222A

[Reply #3 on:]

According to that pic, you have the load on the transistor's base,

[Reply #4 on:]

According to that pic, you have the load on the transistor's base,

what i need to do  ?

[Reply #5 on:]

Have a look at this tutorial. And look at a data sheet for your transistor to make sure you understand which pin is which.

You'll need to get a diode as well.....

[Reply #6 on:]

Your mechanism should be driven exactly as you would drive a heavy-duty relay. I think a 2N2222 might be a little lightweight.
If that's all you've got for a transistor, it may be simpler to use it to drive a relay, and drive the strike from the relay's contacts.

[Reply #7 on:]

this what i do, what wrong

Once you have sorted out the hardware side, you need to get the sketch to compile - which it won't currently.

[Reply #8 on:]

this what i do, what wrong

Once you have sorted out the hardware side, you need to get the sketch to compile - which it won't currently.

you can give my the code? I'm really desperate I want to continue with the project even online I found something similar to what I'm trying to do

[Reply #9 on:]

you can give my the code?

There's really no point trying to move forwards on the code until you have got the hardware right, and then the next step will be to get your code to compile. Which it currently won't, for reasons which should become obvious when you try.

[Reply #10 on:]

i connect like this :



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pdf of ULN2803A:
 http://www.alldatasheet.com/datasheet-pdf/pdf/169423/ETC2/UNL2803.html

now the lock get power but still the software code not work!

Code:

void setup()
{
  //Start serial
  Serial.begin(9600);
  pinMode(13,OUTPUT);
}

void loop()
{

   digitalWrite(13,255);
   delay(1000);
   digitalWrite(13,255);
   delay(1000);
}

Can someone direct me?

[Reply #11 on:]

Code:

digitalWrite(13,255);
   delay(1000);
   digitalWrite(13,255);

what do you expect that to do, other than leave the pin HIGH?

[Reply #12 on:]

sorry the 255 is "HIGH" :-\

[Reply #13 on:]

255 is the same as HIGH, as far as digitalWrite is concerned.
Why write it twice?

[Reply #14 on:]

I think the ULN2803 is already broken, perhaps the Arduino is also damaged.

You have to rewire the connections to the ULN2803. The chip doesn't use a positive voltage, but pin 10 is for the flyback diodes. The pin 10 shoud be connected the + side of the motor (and both should be connected to the (+) of the 9V battery).
The ULN2803 does need a ground. That ground should be connected to the Arduino GND and the (-) of the 9V battery.
Next you have to connect the input and output of the ULN2803 in the right way.