/*
    
    Forum: https://forum.arduino.cc/t/serial-readbytes-and-settimeout/1158069/5
    WOKWI: https://wokwi.com/projects/373030858704846849

*/

#include <SoftwareSerial.h>
SoftwareSerial Serial1(4,5);

char printbuffer[32];
unsigned int rbufLen;     //how many bytes received at once
char rbuf[32]; 

void setup()
{ 
  Serial.begin(9600);  
  while (!Serial) { ; } 
  Serial1.begin(9600);
  Serial1.setTimeout(10); // 10ms timeout
  Serial.println(
    "\nType '1' to read data"
    "\n     '2' for ?"
  );
}

void loop()
{
  if (Serial.available()) {
      char c = Serial.read();
      if (c =='1') {
        sprintf(printbuffer, "Rx: %d \n", rbufLen);  
        Serial.print(printbuffer);
      }
  }    
 if (Serial1.available()) {
     rbufLen=Serial1.readBytes(rbuf,32);  //Serial1.flush();  
 }
}