Send Bitmap on pc to arduino from serial

[sterretje]

Below (over two posts) example code for Arduino and example code for a C# console application that demonstrates the idea of a protocol. I've mostly concentrated on the C# side of things; the Arduino code was quickly hacked together.

Arduino

byte buffer[4096];
byte chunkSize = 32;

void setup()
{
  pinMode(LED_BUILTIN, OUTPUT);
  Serial.begin(57600);
}

void loop()
{
  receiveConfirmEcho();
}


/*
  receive data from PC
  send a message back every chunkSize (32) bytes
  when all data is received, echo the data back to PC
*/
void receiveConfirmEcho()
{
  static uint16_t index;
  static uint32_t lastUpdateTime;

  // read data if available
  while (Serial.available() > 0)
  {
    // update the time that a byte was received
    lastUpdateTime = millis();
    // save in buffer
    buffer[index++] = Serial.read();
    // confirm
    if (index % chunkSize == 0)
    {
      Serial.println(index);
    }
  }

  // on time out, echo the received data back
  if (index != 0 && (millis() - lastUpdateTime > 5000))
  {
    for (uint16_t cnt = 0; cnt < 4096; cnt += chunkSize)
    {
      Serial.write(&buffer[cnt], chunkSize);
      delay(200);
    }

    // reset variables
    index = 0;
    memset(buffer, 0, sizeof(buffer));
  }
}