help me understand what im doing wrong with this if else statement?

Using Arduino Programming Questions
1

hello I am currently new to the Arduino and am starting to learn the code with the starting with electronics tutorial. I wrote the code for the if and else statement but the led wil light up for a split second and then turn off imideatly???? I copied his example after mine didn't work and it ended up with the same result?? im trying to get it so that a or A will light the LED while anything else will turn it off but all I get is a split second where the led will flash?? at first I though it was where the parethesis were located? Please help me understand

void setup() {
Serial.begin(9600);
pinMode(13,OUTPUT);

}

void loop() {
char rx_byte;
if (Serial.available() > 0) {
rx_byte = Serial.read();
if (rx_byte == 'a' || rx_byte == 'A') {
digitalWrite(13, HIGH);
}
else {
digitalWrite(13, LOW);
}
}

}

2

What is the serial monitor line ending set to?
Set it to "none" and retest.

Please remember to use code tags when posting code

3

code tags??

4

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5

On the second pass through loop() (a few microSeconds later), Serial.available() == 0 and the IF falls through to ELSE and turns the LED off.

void loop() {
   static char rx_byte = 'b';
   if (Serial.available() > 0) { 
      rx_byte = Serial.read();
   }
    digitalWrite(13, (rx_byte == 'a' || rx_byte == 'A'));
}

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6

On the second pass through loop() (a few microSeconds later), Serial.available() == 0 and the IF falls through to ELSE and turns the LED off.

Nonsense. The if serial available statement does not have an else statement.

Although, with the piss-poor indentation, that is not so easy to see.

OP: Use Tools + Auto Format, to properly indent your code. And, delete the useless blank lines in the loop() function.