Fast serial output for multiple Ping )) Ultrasonic Sensors

Using Arduino Sensors
11

I think I know how to solve this but ut is not trivial.

You should start the ping ))) on all pins, preferably with direct port manipulation as
notoriou5 proposed.

but you should not use pulseIN for the receiving part as that is blocking code.
Instead you should use pinChangeInterrupts to get the timing of the 4 return signals.

if all 4 are set then one can convert timing to distance

in pseudocode

volatile uint32_t timing[4];

void loop()
{
  // clear timing;
  for (int i=0; i< 4; i++) timing[i] = 0UL;
  
  initializePCI( <pins> ); // to be investigated

  PORTC = pinMask;
  delayMicroseconds(s);


  // WAIT UNTIL READY
  bool ready = false;
  while (!ready)
  {
     ready = true;
     for (int i=0; i<4; i++) ready = ready && timing[i] != 0);
  }

  for (int i=0; i<4; i++) 
  {
    distance[i] = timing[i] /58;
    Serial.println(distance[i]);
  }
}

void PCinterrupt()
{
  pin = ....somecode...
  if (pin == HIGH) return; // wait for the LOW
  timing[pin] = micros();
}

something like that.

read this thread - PinChangeInt library- To attach interrupts to multiple Arduino (Uno/Mega) pins - Exhibition / Gallery - Arduino Forum -

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