I used 5volts and 0(open) as digital inputs but i got problem with its outputs.

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1

Hello Everyone!! im novice in arduino i really need ur help..
i have 2 digital input pins(pin16 & pin17 actually i need 4)
just to test if it really gonna work.What i did is that
i just give 5volts or high to these pins as input data
but what happened there is that the 2 digitalOutput pins respectively
seems doesnt do to the conditions i gave, it seems it can affect the other condition..
Here is my code...

int sPin =16;
int sPin1 =17;
int ledPin7 =7;
int ledPin6 =6;

void setup(){

Serial.begin(9600);

pinMode(ledPin7,OUTPUT);
pinMode(ledPin6,OUTPUT);
pinMode(sPin,INPUT);
pinMode(sPin1,INPUT);

Serial.begin(9600);

}

void loop(){

Serial.println(digitalRead(sPin));
delay(500);

int val = digitalRead(sPin);

if (digitalRead(sPin) == LOW )
{ digitalWrite(ledPin7,HIGH);
}
if (digitalRead(sPin1) == LOW )
{ digitalWrite(ledPin6,HIGH);
}

else
digitalWrite(ledPin7,LOW);
digitalWrite(ledPin6,LOW);

}

what i really want to do there is that,
just have 4 inputs(that would be 5volts/0)
and also give 4 outputs respectively..

i really need ur ideas, suggestions or any other alternatives guyz.. thnx

2

You're not using the built-in pullups, so have you got external ones connected?

3

Try changing these

pinMode(sPin,INPUT);
pinMode(sPin1,INPUT);

to

pinMode(sPin,INPUT_PULLUP);
pinMode(sPin1,INPUT_PULLUP);

As the pins may be floating as AWOL suggests.

4

If you do it with the internal pullups, you might have to reverse your logic, because the input wouldn't change it's state, when you put it on 5V externally. You'd have to switch it to GND instead or use external pull-down resistors instead of the internal pullups.

BTW: the 'else' command is now only working for the lower 'if' routine:

Better put it that way:

if (digitalRead(sPin) == LOW )
{ digitalWrite(ledPin7,HIGH);
}
else
digitalWrite(ledPin7,LOW);

if (digitalRead(sPin1) == LOW )
{ digitalWrite(ledPin6,HIGH);
}
else
digitalWrite(ledPin6,LOW);