Add modem I2C/OLED support.

I2CModem.h

@@ -0,0 +1,40 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef	I2CMODEM_H
+#define	I2CMODEM_H
+
+#include "I2CPort.h"
+#include "Modem.h"
+
+class CI2CModem : public II2CPort {
+public:
+	CI2CModem(IModem* modem);
+	virtual ~CI2CModem();
+
+	virtual bool open();
+
+	virtual bool write(const uint8_t* data, uint16_t length);
+
+	virtual void close();
+
+private:
+	IModem* m_modem;
+};
+
+#endif