Identifying the last character in char to store that in array

Projects Programming
1

I am trying to store a string in an array. So, basically, I'm using C to receive data from an esp32 and send data to an esp32. Because an array is three-dimensional, I'll send a data like this:

        SerialPort.print(maclist[i][0] +"|"+"\t");
        SerialPort.print(maclist[i][1] +"_"+"\t");
        SerialPort.print(maclist[i][2] +"]"+"\t"+"\n");

so this programme output will be like this
00005e0053af| 59_ 1]
and data will be continuously received. I have added a _,|,] for a reference.
While receiving this, I am getting it in char, so every char is coming as a single data.
So I'm using a while loop to store the data I'm getting in a variable. -

char a = char(SerialPort.read());

However, I want to save this character, which is receiving a single piece of data, on a variable as a string .

something like this

00005e0053af
59
1

All the references (_, |,]) I have used for this are to identify when this occurs, stop, and store the result as a string, but I am not getting how to do it. I was doing this, but it wasn't working.

This code is from the receiving end.

String maclist[20][3]; 
for (int i =0 ;i<20;++i) {
      char a = char(SerialPort.read());
      if (!(a== '|')) {
        datamacuser+=a;
        maclist[i][0] = datamacuser;
      }else {
        break;
      }
    }
2

Hello

First problem is that you need to use Serial.available() (instead of your for loop), to make sure there are characters to be read from the input buffer

3

You can have a look at Robin's updated Serial Input Basics to get an idea how to approach serial communication.

It covers the receiving end, you can write the sender that matches the receiver.

4

yes i have that i didn't posted here but .

5

Exactly What I was looking for. Thank You

6

consider

Output:

00005e0053af,59,1
      5  00005e0053af
     59  59
      1  1

Code:

char s [80];

// -----------------------------------------------------------------------------
#define MaxTok  10
char *toks [MaxTok];
int   vals [MaxTok];

int
tokenize (
    char       *s,
    const char *sep )
{
    unsigned n = 0;
    toks [n] = strtok (s, sep);
    vals [n] = atoi (toks [n]);

    for (n = 1; (toks [n] = strtok (NULL, sep)); n++)
        vals [n] = atoi (toks [n]);

    return n;
}

// -----------------------------------------------------------------------------
void dispToks (
    char * toks [])
{
    char s [40];
    for (unsigned n = 0; toks [n]; n++)  {
        sprintf (s, " %6d  %s", vals [n], toks [n]);
        Serial.println (s);
    }
}

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

        Serial.println (s);
        tokenize (s, ",");
        dispToks (toks);
    }
}

// -----------------------------------------------------------------------------
void setup ()
{
    Serial.begin (9600);
}
7

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