Store string of data in SD card received over serial.

Using Arduino Programming Questions
6

I am posting two sketches below by virtue of which two UNOs exchange data over software serial port (SUART Port). The UNO-1 is sending the float type temperature data with 0x05 as a terminating byte. The UNO-2 receives the data and saves in an array. You may practice these setup as a tutorial and then apply the methodology to achieve your objectives.

Transmission Codes

//sender_ code
#include<SoftwareSerial.h>
SoftwareSerial mySUART(2, 3); //SRX, STX

int pin = 0;
int data;
char dataBuffer[20] = "";

void setup()
{
  Serial.begin(9600);
  mySUART.begin(9600);
  analogReference(INTERNAL);
}

void loop()
{
  float tempC = (float)100 * (1.1 / 1024.0) * analogRead(A0); //
  Serial.print("Pressure data = ");//
  Serial.println(tempC, 2);
 
  mySUART.print(tempC); //sends 8-bit ASCII code for each digit/symbol of tempC
 
  mySUART.write(0x05);
  delay(1000);
}

Reception Codes

//sender_ code
#include<SoftwareSerial.h>
SoftwareSerial mySUART(2, 3); //SRX, STX

int data;
char dataBuffer[20] = "";
int i = 0;


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

void loop()
{
  if (mySUART.available() > 0)
  {
    byte x = mySUART.read();
    if (x == 0x05)
    {
      Serial.println(": This data is from SUART Port");
      Serial.println();
      Serial.print("Pressure data from Buffer = ");
      Serial.println(dataBuffer);
      Serial.println("====================");
      i = 0;
    }
    else
    {
      dataBuffer[i] = x;
      Serial.write((char)dataBuffer[i]);
      i++;
    }
  }
}