     Serial.println();
     httpsClient.stop();
     if (statusCode == 400) {
-      flashNumber(TELEGRAM_CHECKSUM_ERROR);
-      return false;
+      return TELEGRAM_CHECKSUM_ERROR;
     } else {
-      flashNumber(SERVER_RESPONSE_ERROR);
-      delay(500);
-      flashNumber(statusCode);
-      return false;
+      return SERVER_RESPONSE_ERROR;
     }
   }
 
   Serial.print("Uploaded telegram of ");
   Serial.print(size);
   Serial.println(" bytes");
-  flashNumber(NO_ERROR);
-
-  return true;
+  return NO_ERROR;
 }
 
 void setup() {

 * Uploads the telegram in the given `buffer` of `size` bytes to the server.
 * Returns `true` on success.
 */
bool uploadTelegram(byte const *buffer, uint16 size) {
  if (!httpsClient.connect(SERVER_HOST, SERVER_PORT)) {
    Serial.print("Failed to connect to " SERVER_HOST ":");
    Serial.print(SERVER_PORT);
    Serial.println();
    flashNumber(SERVER_CONNECT_ERROR);
    return false;
  }

  if (!httpsClient.verify(SERVER_CERTIFICATE_FINGERPRINT, SERVER_HOST)) {
    Serial.println("Certificate verification failed");
    httpsClient.stop();
    flashNumber(SERVER_SSL_ERROR);
    return false;
  }

  httpsClient.print(

    Serial.print(READ_TIMEOUT_MILLIS);
    Serial.println(" ms");
    telegramReader.reset();
    flashNumber(TELEGRAM_READ_TIMEOUT);
  }

  int b = P1_INPUT.read();
