input an integer with Serial.read(); and print it in the console.

Projects Programming
1

Hi guys! I have some questions, could you help me?

I am trying to insert an integer value with serial.read(); but the value showed in the console is the ASCII value.
For instance, when I input a 10, the value showed is 49, then 48 (the ASCII values for 1 and 0, respectively). How can I show the DEC value? please help.

I add the code right here.

Thanks in advance

int asd = 0;
void setup() {

Serial.begin(9600);
}

void loop()
{
int asd = int(Serial.read());
Serial.write(asd);
delay(1500);

}

2

Try this:

Serial.write(asd, DEC);
3

Hi, thanks for the support friend, but when I tried a error code has appeared, and is this:

Arduino: 1.6.0 (Windows 7), Board: "Arduino Mega or Mega 2560, ATmega2560 (Mega 2560)"

prueba_de_impresion.ino: In function 'void loop()':
prueba_de_impresion.ino:11:22: error: call of overloaded 'write(int&, int)' is ambiguous
prueba_de_impresion.ino:11:22: note: candidates are:
In file included from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Stream.h:26:0,
from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/HardwareSerial.h:29,
from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Arduino.h:223,
from prueba_de_impresion.ino:1:
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:54:12: note: size_t Print::write(const char*, size_t)
size_t write(const char buffer, size_t size) {
^
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:54:12: note: no known conversion for argument 1 from 'int' to 'const char'
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:53:20: note: virtual size_t Print::write(const uint8_t*, size_t)
virtual size_t write(const uint8_t buffer, size_t size);
^
C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Print.h:53:20: note: no known conversion for argument 1 from 'int' to 'const uint8_t {aka const unsigned char*}'
Error compiling.

This report would have more information with
"Show verbose output during compilation"
enabled in File > Preferences.

4

Correct answer by CrossRoads.

5

Serial.write expects a byte I believe, not an int.

6

Oh ok, now the code shows the correct numbers, but only shows one byte at a time
If i 'input a 10, shows first 1 and then 0

7

Simple serial servo test code that might have some of what you want.

//zoomkat 7-30-10 serial servo test
//type servo position 0 to 180 in serial monitor
// Powering a servo from the arduino usually *DOES NOT WORK*.

String readString;
#include <Servo.h> 
Servo myservo;  // create servo object to control a servo 

void setup() {
  Serial.begin(9600);
  myservo.attach(9);
  Serial.println("servo-test"); // so I can keep track of what is loaded
}

void loop() {

  while (Serial.available()) {
    char c = Serial.read();  //gets one byte from serial buffer
    readString += c; //makes the String readString
    delay(2);  //slow looping to allow buffer to fill with next character
  }

  if (readString.length() >0) {
    Serial.println(readString);  //so you can see the captured String 
    int n = readString.toInt();  //convert readString into a number
    Serial.println(n); //so you can see the integer
    myservo.write(n);
    readString="";
  } 
}
8

I'm not a huge fan of the String class, so I rewrote zoomkat's code to use char arrays:

//zoomkat 7-30-10 serial servo test
//type servo position 0 to 180 in serial monitor
// Powering a servo from the arduino usually *DOES NOT WORK*.


#include <Servo.h> 
Servo myservo;  // create servo object to control a servo 
char buffer[6];
  
void setup() {
  Serial.begin(9600);
  myservo.attach(9);
  Serial.println("servo-test"); // so I can keep track of what is loaded
}

void loop() {
  int index;  
  while (Serial.available()) {
    index = Serial.readBytesUntil('\n', buffer, 5);  //newline or max of 5 chars
    buffer[index] = '\0';
  
    Serial.println(buffer);  //so you can see the captured String 
    int n = atoi(buffer);  //convert readString into a number
    Serial.println(n); //so you can see the integer
    myservo.write(n);
    buffer[0] = '\0';
  } 
}

It appears the two versions function the same, but without the String class, the code size shrinks from 6042 bytes to 4324 bytes. True, the String class brings a lot to the party, but he also eats a lot while he's there.