     Serial.print(F("Received message on port "));
     Serial.print(port);
     Serial.print(F(": "));
-    Serial.print(nMessage);
+    Serial.print(unsigned(nMessage));
     Serial.println(F(" bytes"));
     }
 

/*******************************************************************************
 * Copyright (c) 2019 Terry Moore, MCCI
 *
 * Permission is hereby granted, free of charge, to anyone
 * obtaining a copy of this document and accompanying files,
 * to do whatever they want with them without any restriction,
 * including, but not limited to, copying, modification and redistribution.
 * NO WARRANTY OF ANY KIND IS PROVIDED.
 *
 *******************************************************************************/

#include <arduino_lmic.h>
#include <hal/hal.h>
#include <SPI.h>
#include <arduino_lmic_hal_boards.h>
#include <arduino_lmic_lorawan_compliance.h>

//
// For compliance tests with the RWC5020A, we use the default addresses
// from the tester.
//

// This EUI must be in little-endian format, so least-significant-byte

    Serial.println(F("Starting"));

    // LMIC init using the computed target
    const auto pPinMap = Arduino_LMIC::GetPinmap_ThisBoard();

    // don't die mysteriously; die noisily.
    if (pPinMap == nullptr) {
