i2c.h

/*! \file i2c.h \brief I2C interface using Philips LPC internal I2C hardware. */
//*****************************************************************************
//
// File Name    : 'i2c.h'
// Title        : I2C interface using Philips LPC internal I2C hardware
// Author       : Pascal Stang - Copyright (C) 2004
// Created      : 2004.05.05
// Revised      : 2004.07.12
// Version      : 0.9
// Target MCU   : ARM, Philips LPC2100-series
// Editor Tabs  : 4
//
// This code is distributed under the GNU Public License
//      which can be found at http://www.gnu.org/licenses/gpl.txt
//
//*****************************************************************************

#ifndef I2C_H
#define I2C_H

#include "global.h"

/* TWSR values (not bits) */
/* Master */
#define TW_START                    0x08
#define TW_REP_START                0x10
/* Master Transmitter */
#define TW_MT_SLA_ACK               0x18
#define TW_MT_SLA_NACK              0x20
#define TW_MT_DATA_ACK              0x28
#define TW_MT_DATA_NACK             0x30
#define TW_MT_ARB_LOST              0x38
/* Master Receiver */
#define TW_MR_ARB_LOST              0x38
#define TW_MR_SLA_ACK               0x40
#define TW_MR_SLA_NACK              0x48
#define TW_MR_DATA_ACK              0x50
#define TW_MR_DATA_NACK             0x58
/* Slave Transmitter */
#define TW_ST_SLA_ACK               0xA8
#define TW_ST_ARB_LOST_SLA_ACK      0xB0
#define TW_ST_DATA_ACK              0xB8
#define TW_ST_DATA_NACK             0xC0
#define TW_ST_LAST_DATA             0xC8
/* Slave Receiver */
#define TW_SR_SLA_ACK               0x60
#define TW_SR_ARB_LOST_SLA_ACK      0x68
#define TW_SR_GCALL_ACK             0x70
#define TW_SR_ARB_LOST_GCALL_ACK    0x78
#define TW_SR_DATA_ACK              0x80
#define TW_SR_DATA_NACK             0x88
#define TW_SR_GCALL_DATA_ACK        0x90
#define TW_SR_GCALL_DATA_NACK       0x98
#define TW_SR_STOP                  0xA0
/* Misc */
#define TW_NO_INFO                  0xF8
#define TW_BUS_ERROR                0x00

// bit defines
#define I2CON_AA            2
#define I2CON_SI            3
#define I2CON_STO           4
#define I2CON_STA           5
#define I2CON_I2EN          6

// defines and constants
#define TWCR_CMD_MASK       0x0F
#define TWSR_STATUS_MASK    0xF8

// return values
#define I2C_OK              0x00
#define I2C_ERROR_NODEV     0x01

// types
typedef enum
{
    I2C_IDLE = 0, I2C_BUSY = 1,
    I2C_MASTER_TX = 2, I2C_MASTER_RX = 3,
    I2C_SLAVE_TX = 4, I2C_SLAVE_RX = 5
} eI2cStateType;

// functions

#define i2cMasterSend       i2cMasterSendNI
#define i2cMasterReceive    i2cMasterReceiveNI

//! Initialize I2C (TWI) interface
void i2cInit(void);

//! Set the I2C transaction bitrate (in KHz)
void i2cSetBitrate(u16 bitrateKHz);

// I2C setup and configurations commands
//! Set the local (AVR processor's) I2C device address
void i2cSetLocalDeviceAddr(u08 deviceAddr, u08 genCallEn);

// Low-level I2C transaction commands 
//! Send an I2C start condition in Master mode
void i2cSendStart(void);
//! Send an I2C stop condition in Master mode
void i2cSendStop(void);
//! Wait for current I2C operation to complete
void i2cWaitForComplete(void);
//! Send an (address|R/W) combination or a data byte over I2C
void i2cSendByte(u08 data);
//! Receive a data byte over I2C  
// ackFlag = TRUE if recevied data should be ACK'ed
// ackFlag = FALSE if recevied data should be NACK'ed
void i2cReceiveByte(u08 ackFlag);
//! Pick up the data that was received with i2cReceiveByte()
u08 i2cGetReceivedByte(void);
//! Get current I2c bus status from TWSR
u08 i2cGetStatus(void);

// high-level I2C transaction commands

//! send I2C data to a device on the bus (non-interrupt based)
u08 i2cMasterSendNI(u08 deviceAddr, u08 length, u08* data);
//! receive I2C data from a device on the bus (non-interrupt based)
u08 i2cMasterReceiveNI(u08 deviceAddr, u08 length, u08 *data);

#endif

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