How can I only read 2nd character of my input in Serial?

[homechennai]

Let's say I serial print "hello", How to serial read only the second letter "e" in "Hello"?

Any Ideas?

[anon10241713]

Do a read, do nothing with that character, then do another read maybe?

[anon10241713]

But having read your question again, if you're doing a serial print of something (which is outbound so to speak) what do you mean by doing a read of that, which is inbound?

[J-M-L]

if you print it's gone. The read can only be done on the destination device. Is that what you are asking for?

[homechennai]

serial print = gives provided output in serial monitor
serial read = reads all the values outputted in the serial monitor

Is this what u asked for?

[J-M-L]

@homechennai

serial read = reads all the values outputted in the serial monitor

Serial.read() reads one byte (packed into the LSB of an int) coming into the Serial port, whatever it's connected to or returns -1 if there was nothing to read

[anon10241713]

Could this be an x-y problem? Perhaps @homechennai you could provide some detail of what you're actually trying to do.

[gcjr]

@homechennai

How to serial read only the second letter "e" in "Hello"?

assuming you mean the 2nd character of any "line" received

e - hello
h - charlie
u - duck

char buf [80];

void
loop (void)
{
    if (Serial.available())  {
        int n = Serial.readBytesUntil ('\n', buf, sizeof(buf)-1);
        buf [n] = '\0';
        Serial.print (buf [1]);
        Serial.print (" - ");
        Serial.println (buf);
    }
}

void
setup (void)
{
    Serial.begin (9600);
}

[homechennai]

//6=RightPWM
//5=LeftPWM
//10=RightControlCW
//11=RightControlACW
//4=LeftControlCW
//3=LeftControlACW

bool data;

int Rctrl = 11;
int Lctrl = 3;
int Rpwm = 6;
int Lpwm = 5;

int RpwmVal = 255;
int LpwmVal = 255;

int distance = 100;

void setup() {
Serial.begin(9600);

pinMode(Rctrl, OUTPUT);
pinMode(Rpwm, OUTPUT);
pinMode(Lctrl, OUTPUT);
pinMode(Lpwm, OUTPUT);
}

void loop(void) {
if (Serial.available()) {
  data = Serial.find("front");
}

Serial.print(data);

if (data == true) {
  analogWrite(Rpwm, RpwmVal);     //pwm
  analogWrite(Lpwm, LpwmVal);
  
  digitalWrite(Rctrl, HIGH);      //control
  digitalWrite(Lctrl, HIGH); 

  delay(341*0.047506*distance*1.2);

  digitalWrite(Rctrl, LOW);
  digitalWrite(Lctrl, LOW);
  
  delay(1000);
  data = false;
}
else {
delay(1000);
}
}

See, Im trying to make a arduino car where in if I type front100 in serial monitor, It travels FRONT - 100cm

What I have coded so far :
If I type "front" in the serial monitor, It goes front.

What I can't code :
If I type "front100", the last 3 digits are considered as distance and it travels the distance.

[anon10241713]

So it was an xy issue

Have a look at Robin2's serial tutorial for some ideas on how to structure and read data.

edit: why did you mark one post as a solution, but then still say in the next post you don't know how to do it?

[homechennai]

its a DELAY. Thanks for help anywaysss

[gcjr]

what about?
adding a space before the decimal makes it easier to recognize

char buf [80];

void
loop (void)
{
    if (Serial.available())  {
        int n = Serial.readBytesUntil ('\n', buf, sizeof(buf)-1);
        buf [n] = '\0';

        char cmd [20];
        int  val;
        sscanf (buf, "%s %d", cmd, &val);

        Serial.print ("  ");
        Serial.print (cmd);
        Serial.print ("  ");
        Serial.println (val);
    }
}

void
setup (void)
{
    Serial.begin (9600);
}