You need to check if there are characters to read first.
if (Serial.available>3){ // 4 character ready?
char one = Serial.read();
char two = Serial.read();
char three = Serial.read();
char four = Serial.read();
i have my code here where i am trying to read the variable value but it shows nothing in pin13. as i try to blink led 13 once the data is recvd..it compiles but doesnot go high low as it should upon reception of code i want to check wheather i am recvng propoer code and are there any mistakes in this program?
int led = 13;
void setup()
{
char myarray[4] = {'A','B','C','D'}; // char of strings which i want to recv
char x;
int led = 13;
pinMode(led, OUTPUT);
}
void loop()
{
char x;
int led = 13;
pinMode(led, OUTPUT);
while (Serial.available() > 0)
{
if (Serial.read() == 'A') // here i want to say that if my string starts with A it is recvd n stored in x
{
char x = Serial.read();
}
else if (Serial.read() == 'B') // here i want to say that if my string starts with B it is recvd n stored in y
{
char y = Serial.read();
}
else if (Serial.read() == 'C') // here i want to say that if my string starts with C it is recvd n stored in w
{
char w = Serial.read();
}
else if (Serial.read() == 'D') // here i want to say that if my string starts with D it is recvd n stored in z
{
char z = Serial.read();
}
if (char x = '1');
{
digitalWrite(led, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(led, LOW); // turn the LED off by making the voltage LOW
delay(1000); // wait for a second
}
}
}
ACTUALLY,
IF there can be some way where i can read my x ,y,w,z, values? i tried doing serial.print(x);
the code is here:
void setup()
{
char myarray[4] = {'A','B','C','D'};
char x;
}
void loop()
{
while (Serial.available() > 0)
{
if (Serial.read() == 'A')
{
char x = Serial.read();
}
else if (Serial.read() == 'B')
{
char y = Serial.read();
}
else if (Serial.read() == 'C')
{
char w = Serial.read();
}
else if (Serial.read() == 'D')
{
char z = Serial.read();
}
char x;
Serial.print(x);
}
}
i just want to read what x has exactly?
help me to do so kindly suggst somehing and just make this prog running
i didnt get u??
u said that:
What are the chances that "x" is not -1, if the character that you knew was there was 'A'?
can u elaborate?
i am sending A from serial monitor so from where -1 comes?
if trying to say something else kindly elaborate since i am a learner in arduino.
vanashree:
i didnt get u??
u said that:
What are the chances that "x" is not -1, if the character that you knew was there was 'A'?
can u elaborate?
i am sending A from serial monitor so from where -1 comes?
if trying to say something else kindly elaborate since i am a learner in arduino.
try this.
You will take one char from the serial buffer (if available) and if it matches any of your four letters or '1' it will behave accordingly.
int led = 13;
void setup()
{
Serial.begin(9600);
pinMode(led, OUTPUT);
}
void loop()
{
if (Serial.available()) // is there anything in the serial buffer?
{
char myChar = Serial.read();
if (myChar == 'A') // is the char you received an 'A' ??
{
Serial.println(myChar);
}
else if (myChar == 'B') // here i want to say that if my string starts with B it is recvd n stored in y
{
Serial.println(myChar);
}
else if (myChar == 'C') // here i want to say that if my string starts with C it is recvd n stored in w
{
Serial.println(myChar);
}
else if (myChar == 'D') // here i want to say that if my string starts with D it is recvd n stored in z
{
Serial.println(myChar);
}
if (myChar = '1');
{
digitalWrite(led, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(led, LOW); // turn the LED off by making the voltage LOW
}
}
}
A simple example of capturing characters sent from the serial monitor and operating the arduino LED.
// zoomkat 8-6-10 serial I/O string test
// type a string in serial monitor. then send or enter
// for IDE 0019 and later
int ledPin = 13;
String readString;
void setup() {
Serial.begin(9600);
pinMode(ledPin, OUTPUT);
Serial.println("serial on/off test 0021"); // so I can keep track
}
void loop() {
while (Serial.available()) {
delay(3);
char c = Serial.read();
readString += c;
}
if (readString.length() >0) {
Serial.println(readString);
if (readString == "on")
{
digitalWrite(ledPin, HIGH);
}
if (readString == "off")
{
digitalWrite(ledPin, LOW);
}
readString="";
}
}
thanks i got it workig.i useda another logic n have attached my prog.
thanks a lot now its working.i just have one smaall isssue.and that is in last few if elese where on recving 1 or 2 or 3 in my 7th strin i want to make my respective pin high onlly for 2 seconds and then back to low until i recieve next codde.
i have posted my problem in new topic already.
