Problems with atoi()

Forum 2005-2010 (read only) Software Syntax & Programs
1

I'm using the following code which basically echoes onto terminal whatever I send to the arduino. However, atoi only works to convert the ascii code to integer, so i guess I shouldn't have been surprised that the terminal echoed 0 for all non numeric characters. Is there someway to fix this?

#include <stdlib.h>
void setup(){
//Spi.mode((0<<CPOL) | (1 << CPHA)); // set SPI mode 1
Serial.begin(9600);
Serial.print(25, DEC);
delay(200);
Serial.print(17, DEC);
delay(5);

}
unsigned long time;
int command=0;
int array[20];
     int num=0;
     char* val="0";
void loop(){
    


    while(Serial.available()>0){
 
      val[0]=Serial.read();
    array[num]=atoi(val);
        if(array[num]!=int('

)){  
          Serial.print(array[num]);
     delay(50);
       num++;
      //  array[num]='\0';
       }else{
           
        for(int i=0; i<num; i++){  
   
        Serial.print(array[i]);
        delay(50);
        }
         while(num>=0){      //clears array
             array[num]=' ';
             num--;
         }
      num=0;
       
       }
   }
 
 
}

2

Only call atoi if

if (val [0] >= '0' && val [0] <= '9')
3

Thanks, but is there some way to convert the non numeric characters too from ascii to string?

4

Your question doesn't really make sense. The non-numeric ("ascii") characters are already a string. What is there to convert?

5

sorry about the terminology. Right now, serial.read gets the ascii chars and the arduino outputs it on the terminal as decimal values. I want it to output exactly the same chars that I inputed.

6

So...."Serial.print(Serial.read())" ???

7

Here's what I have changed so far. Now I got it working that the terminal outputs exactly the same nonumeric chars I input. But now, any numbers i enter gets outputted as "."

#include <stdlib.h>
void setup(){
//Spi.mode((0<<CPOL) | (1 << CPHA)); // set SPI mode 1
Serial.begin(9600);
Serial.print(25, DEC);
delay(200);
Serial.print(17, DEC);
delay(5);

}
unsigned long time;
int command=0;
int array[20];
     int num=0;
     char* val="0";
void loop(){
    


    while(Serial.available()>0){
 
      val[0]=Serial.read();
      if (val [0] >= '0' && val [0] <= '9'){
    array[num]=atoi(val);
      }else{
        array[num]=val[0];
      }
        if(array[num]!=int('

)){  
          Serial.print(array[num]);
     delay(50);
       num++;
      //  array[num]='\0';
       }else{
           
        for(int i=0; i<num; i++){  
   if (array[i] >= '0' && array[i]<= '9'){
        Serial.print(array[i], DEC);
        delay(50);
   }else{
   Serial.print(array[i], BYTE);
   delay(50);
   }
        }
         while(num>=0){      //clears array
             array[num]=' ';
             num--;
         }
      num=0;
       
       }
   }
 
 
}

8

nvm, i got it working, except that it take a considerable time for a response after i type something on the terminal for something to return. is there anything that I'm doing that's making it so slow?

9

is there anything that I'm doing that's making it so slow?

All those "delay"s?

But now, any numbers i enter gets outputted as "."

because:

array[num]=atoi(val);
10

I think a lot of your problems are caused by the word "DEC". You may want to check out Serial.print() - Arduino Reference

Good luck!