Converting bytes to char when receiving from 433mhz

Using Arduino Programming Questions
1

I am trying to combine the buf[] received into a char (strRec).
The Serial.print((char)buf[i]); prints the correct information received.

This is not a project so any assistance would be appreciated.

#include <VirtualWire.h>

/*
   sent example =  A001*, A002* etc
*/

void setup()
{
  Serial.begin(115200); // Debugging only
  Serial.println("Receiver setup");

  // Initialise the IO and ISR
  //  vw_set_ptt_inverted(true); // Required for DR3100
  vw_set_rx_pin(11);           // Arduino pin (default 11)
  vw_setup(2000);             // Bits per sec
  vw_rx_start();              // Start the receiver PLL running
}


void loop() {
  char strRec;
  uint8_t buf[VW_MAX_MESSAGE_LEN];
  uint8_t buflen = VW_MAX_MESSAGE_LEN;
  if (vw_get_message(buf, &buflen)) // Non-blocking
  {

    digitalWrite(13, true); // Flash a light to show received good message
    // Message with a good checksum received, dump it

    for ( int i = 0; i < buflen; i++)
    {
      **strRec += ((char)buf[i]);**
      Serial.print((char)buf[i]);
    }
    Serial.print(" received: "); Serial.print(strRec);
    Serial.println();
    digitalWrite(13, false);
    delay(200);
  }
}
2

strRec is a single character - it isn't going to hold a very large sum.
What do you want here?

3

I want to add the character's received into one string.

4

If your received message is buflen chars, just copy them over

if (vw_get_message(buf, &buflen)) // Non-blocking
  {
    char newBuffer[VW_MAX_MESSAGE_LEN];
    memcpy(newBuffer, buf, buflen);  // copy the contents
    newBuffer[buflen] = '\0';  make sure string is nul terminated
    Serial.print(newBuffer);
  }
5

vw_get_message() stays right there until the ENTIRE MESSAGE is received.
That function Blocks! The code that uses the data expects it all, there's no exit or re-entry, execution stays Locked on vw_get_message that receives chars over time.

Beyond that.... '\0' is ASCII 48, text zero. The NUL is ASCII 0.

6

Perfect thank you.

7

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