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diff --git a/recipes/i2c/files/i2c.h b/recipes/i2c/files/i2c.h
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+/****************************************************************************
+*
+*   Copyright (c) 2006 Dave Hylands     <dhylands@gmail.com>
+*
+*   This program is free software; you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License version 2 as
+*   published by the Free Software Foundation.
+*
+*   Alternatively, this software may be distributed under the terms of BSD
+*   license.
+*
+*   See README and COPYING for more details.
+*
+****************************************************************************/
+/**
+*
+*   @file   i2c.h
+*
+*   @brief  Global definitions for interfacing with the AVR TWI (aka I2C)
+*           hardware
+*
+****************************************************************************/
+/**
+*   @defgroup   xxx   Readable version of xxx.
+*
+*   @brief   Brief description of what xxx does.
+*
+*   Longer description of what xxx does.
+*
+****************************************************************************/
+
+#if !defined( I2C_H )
+#define I2C_H               /**< Include Guard                             */
+
+/* ---- Include Files ---------------------------------------------------- */
+
+#include <inttypes.h>
+
+#if !defined( CONFIG_H )
+#   include "Config.h"
+#endif
+
+
+/**
+ *  @addtogroup I2C
+ *  @{
+ */
+
+/* ---- Constants and Types ---------------------------------------------- */
+
+/**
+ *  Error Codes
+ */
+
+#define I2C_ERROR_NONE               0  // No Error
+#define I2C_ERROR_ADDR_NACK         -1  // No response to SLA+R/W
+#define I2C_ERROR_DATA_NACK         -2  // NACK during data transmission
+#define I2C_ERROR_ARBITRATION_LOST  -3  // Lost arbitration
+#define I2C_ERROR_BAD_LEN           -4  // Length is wonky
+#define I2C_ERROR_BAD_CRC           -5  // CRC failed
+#define I2C_ERROR_BUS_ERROR         -6  // Someting weird on the i2c bus
+
+typedef int8_t  I2C_Error_t;
+
+/**
+ *  Since we're loosely following the SMBus spec, we restrict the amount
+ *  of data in each transaction to 32 bytes.
+ */
+
+#define I2C_MAX_DATA_LEN    32
+
+/**
+ *  I2C_Addr_t can contain the address of any device on the bus. This
+ *  module only supports 7 bit addressing.
+ */
+
+typedef uint8_t I2C_Addr_t;
+
+/**
+ *  The I2C_CRC macro can be used to remove all CRC support at compile time.
+ */
+
+#if CFG_I2C_USE_CRC
+#   define  I2C_CRC(x)  x
+#else
+
+#   define  I2C_CRC(x)
+#endif
+
+
+/**
+ *  I2C_Data_t encapsulates the data being read or written on the i2c bus.
+ *  This module follows the SMBus spec, whihch specifies a maximum payload
+ *  of 32 bytes.
+ */
+
+typedef struct
+{
+#if CFG_I2C_USE_CRC
+    uint8_t     m_crc;
+#endif
+
+
+    //  For reads, m_len is the number of bytes actually read (doesn't include
+    //  the CRC - if present). If a block transfer was performed which has a 
+    //  length byte, this length will include the length byte.
+
+    uint8_t     m_len;
+
+    // Note: Under SMBus, a block write can consist of a command, a length,
+    //       32 bytes of payload, and a CRC.
+    //
+    // A read response can consist of a length, 32 bytes of data, and a CRC.
+
+    uint8_t     m_data[ I2C_MAX_DATA_LEN  + 2]; // +1 for the command, +1 for length
+
+} I2C_Data_t;
+
+/* ---- Variable Externs ------------------------------------------------- */
+
+/**
+ *  Description of variable.
+ */
+
+/* ---- Function Prototypes ---------------------------------------------- */
+
+/*
+ *  Just include prototypes here. Put full descriptions in the .c files.
+ */
+
+/** @} */
+
+#endif /* I2C_H */
+
+