Hey Arduino Friends,
i have a question about the digital Pins. Because i am using Arduino Due with enough digital Pins, i want to connect some Buttons (until WIFI and App is finished to takes control) and i dont want to use my breadboard.
So i used an 2x pin stripe to connect the Button / Wires. Now i want to check the Button State programmatically. It works but i am not sure if it is a good solution (electronics).
Without a diagram or code we can't tell you... And what's "2x pin strip" or a 2 PIN Button"?
I believe it's a push button you are connecting. Normally I check the button state using digitalRead and I dont find any issue with that.
Sorry, the image can not be uploaded. Trying again.
I am using some normal Push Button with two wires and soldered with 2 Pins to connect it directly to the Ar. Due.
My Code looks like this:
Setup:
pinMode(PIN_BUTTON_2_OUT, OUTPUT);
digitalWrite(PIN_BUTTON_2_OUT, LOW);
pinMode(PIN_BUTTON_2_IN, INPUT);
digitalWrite(PIN_BUTTON_2_IN, HIGH);
Loop:
if(digitalRead(PIN_BUTTON_2_IN)==LOW){ Serial.print("Button 2 is pressed!\r\n"); }
If it's just a normal push button than this is a bit wasteful. Just connect one side to GND and the other to a pin. Then you don't need the:
pinMode(PIN_BUTTON_2_OUT, OUTPUT);
digitalWrite(PIN_BUTTON_2_OUT, LOW);
A normal button doesn't need a output.
Then you're left with on input on which you turn on the internal pull up. You can do that with
pinMode(PIN_BUTTON_2_IN, INPUT);
digitalWrite(PIN_BUTTON_2_IN, HIGH);
But you can also do it in one line, which I find more clear
pinMode(PIN_BUTTON_2_IN, INPUT_PULLUP);
Little code tip, a line is done after a { or a ;. So:
if(digitalRead(PIN_BUTTON_2_IN) == LOW){
Serial.println("Button 2 is pressed!");
}
Makes the code clearer.
And by using println() you can skip the whole line end stuff 
A photo of the connection is very difficult to understand, a schema drawn in Fritzing or any other tool is easily readable.
I normally use the code approach you mentioned in the post.
To connect switches I used the Internal pull-up resistor approach mentioned in post Gammon Forum : Electronics : Microprocessors : Switches tutorial
Thank u both for explanation and the Link.
pinMode(PIN_BUTTON_2_IN, INPUT_PULLUP);
...is better to understand.
I used GND and the internal pullup before. Works well. the Problem is, that i need to use some more Buttons and Sliders and the Wires between Breadboard, Arduino, Buttons, ... are driving me crazy. :o)
So while development i would like to connect the Buttons directly to 2 GPIO Pins. But im still not sure if the Code is 'electrically' ok?!
pinMode(PIN_BUTTON_2_OUT, OUTPUT);
digitalWrite(PIN_BUTTON_2_OUT, LOW);
pinMode(PIN_BUTTON_2_IN, INPUT);
digitalWrite(PIN_BUTTON_2_IN, HIGH);
Yes it is. But adding all the LOW outputs just to create GND's for switches doesn't help the code being readable.
If you need multiple buttons in a test situation and a breadboard is driving you crazy (tip, small solid core wire like this already keeps it more manageable) then just get out your soldering iron and make a small PCB
Small PCB :), that's what i do normally after a prototyping in breadboard. Wires drives me crazy :), takes me an hr or two to etch a simple home made pcb and drill holes.
But you don't need to make it that fancy... Just a prototype PCB, takes you 5 minutes. Just solder on more buttons then you ever need and you can re-use it every time you need buttons.
Thank u both. 
Since it is my first project and I have no experience with electrical engineering, I am pleased with all instructions. However, since almost all components will be shipped from China, I will buy next week a prototype pcb in the electronics shop in the city.
Maybe i will try an playstation controller because it seems to be connected with something like spi communication.
