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I am using raspberry pi 4b along with Freenova kit. I am trying to make the LED blink however it does not blink instead it is ON of the time. I have tried different code (C,Python,Java) but none of it seems to work. What am I doing wrong? below is my Java code that I execute in Processing. None of it works, why? I want Java code the most.

import processing.io.*;
int ledPin = 17;
//define ledPin
boolean ledState = false;
//define ledState
void setup() {
    size(100, 100);
    frameRate(1);
    //set frame rate
    GPIO.pinMode(ledPin, GPIO.OUTPUT);
    //set the ledPin to output mode
}
void draw() {
    ledState = !ledState;
    if (ledState) {
        GPIO.digitalWrite(ledPin, GPIO.HIGH);
        //led on
        background(255, 0, 0); //set the fill color of led on
    } else {
        GPIO.digitalWrite(ledPin, GPIO.LOW);
        //led off
        background(102); //set the fill color of led off
    }
}

Python code:

import RPi.GPIO as GPIO
import time

ledPin = 11    # define ledPin

def setup():
    GPIO.setmode(GPIO.BOARD)       # use PHYSICAL GPIO Numbering
    GPIO.setup(ledPin, GPIO.OUT)   # set the ledPin to OUTPUT mode
    GPIO.output(ledPin, GPIO.LOW)  # make ledPin output LOW level 
    print ('using pin%d'%ledPin)

def loop():
    while True:
        GPIO.output(ledPin, GPIO.HIGH)  # make ledPin output HIGH level to turn on led
        print ('led turned on >>>')     # print information on terminal
        time.sleep(1)                   # Wait for 1 second
        GPIO.output(ledPin, GPIO.LOW)   # make ledPin output LOW level to turn off led
        print ('led turned off <<<')
        time.sleep(1)                   # Wait for 1 second

def destroy():
    GPIO.cleanup()                      # Release all GPIO

if __name__ == '__main__':    # Program entrance
    print ('Program is starting ... \n')
    setup()
    try:
        loop()
    except KeyboardInterrupt:   # Press ctrl-c to end the program.
        destroy()

C code:

#include <wiringPi.h>
#include <stdio.h>

#define  ledPin    0    //define the led pin number

void main(void)
{   
    printf("Program is starting ... \n");
    
    wiringPiSetup();    //Initialize wiringPi.
    
    pinMode(ledPin, OUTPUT);//Set the pin mode
    printf("Using pin%d\n",ledPin); //Output information on terminal
    while(1){
        digitalWrite(ledPin, HIGH);  //Make GPIO output HIGH level
        printf("led turned on >>>\n");      //Output information on terminal
        delay(1000);                        //Wait for 1 second
        digitalWrite(ledPin, LOW);  //Make GPIO output LOW level
        printf("led turned off <<<\n");     //Output information on terminal
        delay(1000);                        //Wait for 1 second
    }
}

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    Post a photo of your wiring. – CoderMike Nov 2 '20 at 12:11
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    Wiring in photo looks correct. Is you ribbon cable round the right way at the Pi end. Post a photo including ribbon cable at both ends. – CoderMike Nov 2 '20 at 12:27
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    It is, otherwise the led would not be ON, it is not a problem with the wiring – newbie Nov 2 '20 at 12:29
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    The led could be connected to other power pins if the cable is wrong. – CoderMike Nov 2 '20 at 12:30
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    No, cable is not wrong, I have tried literally all combinations. it is not. – newbie Nov 2 '20 at 12:34
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Your code and breadboard wiring looks fine to me. Your Python code works on my Pi.

I suspect your ribbon cable is the wrong way round either at the Pi end or the breadboard end. Your T Cobbler board could also be faulty.

enter image description here

enter image description here

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    I have added more pictures, on one it is on but doesn't flash, on the other one it is not even on. Do you have raspberry pi 4b a swell? – newbie Nov 2 '20 at 13:23
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    Yes, this is a Pi4B. – CoderMike Nov 2 '20 at 13:25
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    Your 3rd photo (LED on) - the cable at the Pi end is wrong. – CoderMike Nov 2 '20 at 13:29
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    so I assume that on 2nd photo it is connected correctly (It is connected like that at the moment), why led doesn't work at all then? – newbie Nov 2 '20 at 13:30
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    Thanks Mike for your help :) – newbie Nov 2 '20 at 13:37

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