MPC4451 I2C support

Marlin/src/HAL/HAL_LPC1768/include/Wire.h

@@ -0,0 +1,58 @@
+/*
+  TwoWire.h - TWI/I2C library for Arduino & Wiring
+  Copyright (c) 2006 Nicholas Zambetti.  All right reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+  Modified 2012 by Todd Krein (todd@krein.org) to implement repeated starts
+*/
+
+// Modified for use with the mcp4451 digipot routine
+
+#if defined(TARGET_LPC1768)
+
+#ifndef TwoWire_h
+#define TwoWire_h
+
+#include <inttypes.h>
+
+class TwoWire
+{
+
+  public:
+//    TwoWire();
+    void begin();
+    void beginTransmission(uint8_t);
+    uint8_t endTransmission(void);
+    size_t write(uint8_t);
+};
+
+//extern TwoWire Wire;//
+
+TwoWire Wire;
+
+  ////////////////////////////////////////////////////////////////////////////////////////
+  extern "C" uint8_t digipot_mcp4451_start(uint8_t sla);
+  extern "C" void digipot_mcp4451_init(void);
+  extern "C" uint8_t digipot_mcp4451_send_byte(uint8_t data);
+
+
+  void TwoWire::beginTransmission(uint8_t sla) { digipot_mcp4451_start(sla);}
+  void TwoWire::begin(void) {digipot_mcp4451_init();}
+  size_t TwoWire::write(uint8_t data) {return digipot_mcp4451_send_byte(data);}
+  uint8_t TwoWire::endTransmission(void) {return 1;}
+
+#endif
+#endif  // TARGET_LPC1768