Pins on the Arduino

Using Arduino General Electronics
1

Hi Everyone,
Quick Question for you lot.

Im trying to figure out how much voltage comes out of each pin, i dont have a multimeter or anything on me so im not sure what it is or where to find it (im new to all this).

Here is my code and my Circuit.

int redPin = 13;
int greenPin = 12;
int bluePin = 11;

String myColour;
String msg = "What Colour do you want to Display? ";
String msg2 = "(Red,Green,Blue,All,Off)";

void setup()
{
Serial.begin(115200);
pinMode(redPin,OUTPUT);
pinMode(greenPin,OUTPUT);
pinMode(bluePin,OUTPUT);

}

void loop()
{
Serial.println(msg);
Serial.println(msg2);
while (Serial.available()==0)
{

}
myColour = Serial.readString();

if (myColour == "red" || myColour == "Red" || myColour == "R" || myColour == "r" || myColour == "RED" )
{
digitalWrite(redPin,HIGH);
digitalWrite(greenPin,LOW);
digitalWrite(bluePin,LOW);
}

if (myColour == "green" || myColour == "Green" || myColour == "G" || myColour == "g" || myColour == "GREEN" )
{
digitalWrite(redPin,LOW);
digitalWrite(greenPin,HIGH);
digitalWrite(bluePin,LOW);
}

if (myColour == "blue" || myColour == "Blue" || myColour == "B" || myColour == "b" || myColour == "BLUE" )
{
digitalWrite(redPin,LOW);
digitalWrite(greenPin,LOW);
digitalWrite(bluePin,HIGH);
}

if (myColour == "all" || myColour == "All" || myColour == "ALL" )
{
digitalWrite(redPin,HIGH);
digitalWrite(greenPin,HIGH);
digitalWrite(bluePin,HIGH);
}
if (myColour == "off" || myColour == "OFF" || myColour == "Off" )
{
digitalWrite(redPin,LOW);
digitalWrite(greenPin,LOW);
digitalWrite(bluePin,LOW);
}

}

Thanks.

photoOfCircuit.jpg
photoOfCircuit.jpg960×1280 398 KB

WireDiagram.png

photoOfCircuit.jpg
photoOfCircuit.jpg960×1280 398 KB

WireDiagram.png

2

Please read the forum rules before posting:
"General Guidance and How to use the Forum - General Electronics - Arduino Forum"

Seriously?
You don't know how to rotate a photo ?

3

With the Arduino pictured 0Volts and about 5Volts.

4

"arduino uno digital output voltage - Google Search"

5

The voltage out of a pin depends, predominantly, on the supply voltage to the processor and the current from the pin. The higher the current, the lower the voltage. See the processor data sheet.

6

raschemmel:
Please read the forum rules before posting:
"General Guidance and How to use the Forum - General Electronics - Arduino Forum"

Seriously?
You don't know how to rotate a photo ?

as you can see, i have two posts. Please dont deep it my guy.

7

Hi everyone,

Just trying to to understand how my circuit works, from the image below, you can see that there are 3 pins which are connected to 3 LEDs.

Red LED
Forward Voltage: 2.1V
Angle: 60 deg
Luminous intensity: 275 mCd (@20mA)
Max forward current: 25mA
Lens type: Diffused

Green LED
Forward Voltage: 2.1V
Angle: 60 deg
Luminous intensity: 35 mCd (@20mA)
Max forward current: 25mA
Lens type: Diffused

Blue LED
Forward Voltage: 3.1V
Angle: 60 deg
Luminous intensity: 500 mCd (@20mA)
Max forward current: 25mA
Lens type: Diffused

Im pretty sure the arduino pins output 5v each
My 3 Resistors are 330 ohms each aswell. This then connects to the ground.

What i need is for someone to explain the voltage, current, and resistance and where it is on the wiring diagram.
I understand ohms law im just getting cofused.

WireDiagram.png

WireDiagram.png

WireDiagram.png

WireDiagram.png

8

You will find simple information on driving leds here

Beyond that what xactly is it you dont understand?

9

jacklythgoee:
Please dont deep it my guy.

Can we have that again in English?

Steve

10

Can you pls work out it and then explain it. I cannot get my head around any recources, as my level of learning its all jibberish to me.

11

What i need is for someone to explain the voltage, current, and resistance and where it is on the wiring diagram.

Is this some kind of assignment ?

12

No, i am at my workplace doing an apprenticeship. My Manager bought my the elegoo arduino R3 kit and im making my own mini projects and then writing the documentation about it just for evidence and to see my progression. However, my manager would like me to explain how the circuit works aswell.

13

slipstick:
Can we have that again in English?

Steve

Clearly, you are a boomer "Steve"

14

Start by putting the values that you know on the diagram, such as voltages, and label the LEDs with their colours

15

Topics on the same subject merged so that the full context of the questions is available

Cross-posting is against the rules of the forum. The reason is that duplicate posts can waste the time of the people trying to help. Someone might spend 15 minutes (or more) writing a detailed answer on this topic, without knowing that someone else already did the same in the other topic.

Repeated cross-posting will result in a timeout from the forum.

In the future, please take some time to pick the forum board that best suits the topic of your question and then only post once to that forum board. This is basic forum etiquette, as explained in the sticky "How to use this forum - please read." post you will find at the top of every forum board. It contains a lot of other useful information. Please read it.

Thanks in advance for your cooperation.

16

jacklythgoee:
Im pretty sure the arduino pins output 5v each

Get / buy a multimeter and measure it :wink: Or use an analog input pin to measure the voltage :wink:

The output voltage depends on the load (and temperature). Download the datasheet of the processor (328P for an Uno) and check the VOH; there are some graphs. At 0 mA load, it will be 5 V; at 10 mA, it will be around 4.75 V, and at 20 mA, it will be around 4.48 V; temperature 25 degrees Celsius.

Most of us will ignore the decreased voltage caused by load when using LEDs but it can be important if you're also driving other electronics from te same pin.

17

my manager would like me to explain how the circuit works

Start by asking your manager to supply you with a multimeter. Even a cheap one from Ebay will be good enough for what you are doing

18

Pay attention !
In your Original Post you posted code without using
the CODE button ("<>").
You posted a photo without rotating it.
In reply #3 I posted a link to arduino digital output
voltages. Go back and highlight your code and then click on CODE button (<>), then use the photo viewer to rotate your photo and reupload it while unchecking your original photo. It's common courtesy to orient photos for easy viewing before posting them and it's common sense to Google your question before posting on the forum to save everyone's time and it's forum rules to NOT cross-post. And "Boomers" aren't the only ones who can't understand what you are trying to say. The output voltage of an arduino digital pin is not that hard to find on the web if you make an effort to do so. And then order a multimeter.