📄 lpc177x_8x_i2c.c
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/**********************************************************************
* $Id$ lpc177x_8x_i2c.c 2011-06-02
*//**
* @file lpc177x_8x_i2c.c
* @brief Contains all functions support for I2C firmware library
* on LPC177x_8x
* @version 1.0
* @date 02. June. 2011
* @author NXP MCU SW Application Team
*
* Copyright(C) 2011, NXP Semiconductor
* All rights reserved.
*
***********************************************************************
* Software that is described herein is for illustrative purposes only
* which provides customers with programming information regarding the
* products. This software is supplied "AS IS" without any warranties.
* NXP Semiconductors assumes no responsibility or liability for the
* use of the software, conveys no license or title under any patent,
* copyright, or mask work right to the product. NXP Semiconductors
* reserves the right to make changes in the software without
* notification. NXP Semiconductors also make no representation or
* warranty that such application will be suitable for the specified
* use without further testing or modification.
**********************************************************************/
/* Peripheral group ----------------------------------------------------------- */
/** @addtogroup I2C
* @{
*/
/* Includes ------------------------------------------------------------------- */
#include "lpc177x_8x_i2c.h"
#include "lpc177x_8x_clkpwr.h"
#include "lpc177x_8x_pinsel.h"
/* Private Types -------------------------------------------------------------- */
/** @defgroup I2C_Private_Types I2C Private Types
* @{
*/
/**
* @brief I2C device configuration structure type
*/
typedef struct
{
uint32_t txrx_setup; /* Transmission setup */
int32_t dir; /* Current direction phase, 0 - write, 1 - read */
} I2C_CFG_T;
/**
* @}
*/
/* Private Variables ---------------------------------------------------------- */
/**
* @brief II2C driver data for I2C0, I2C1 and I2C2
*/
static I2C_CFG_T i2cdat[3];
static uint32_t I2C_MasterComplete[3];
static uint32_t I2C_SlaveComplete[3];
static uint32_t I2C_MonitorBufferIndex;
/* Private Functions ---------------------------------------------------------- */
/* Get pointer to expected I2C */
static LPC_I2C_TypeDef* I2C_GetPointer(en_I2C_unitId compId);
/* Get I2C number */
static int32_t I2C_getNum(LPC_I2C_TypeDef *I2Cx);
/* Generate a start condition on I2C bus (in master mode only) */
static uint32_t I2C_Start (LPC_I2C_TypeDef *I2Cx);
/* Generate a stop condition on I2C bus (in master mode only) */
static void I2C_Stop (LPC_I2C_TypeDef *I2Cx);
/* I2C send byte subroutine */
static uint32_t I2C_SendByte (LPC_I2C_TypeDef *I2Cx, uint8_t databyte);
/* I2C get byte subroutine */
static uint32_t I2C_GetByte (LPC_I2C_TypeDef *I2Cx, uint8_t *retdat, Bool ack);
/* I2C set clock (hz) */
static void I2C_SetClock (LPC_I2C_TypeDef *I2Cx, uint32_t target_clock);
/*--------------------------------------------------------------------------------*/
/********************************************************************//**
* @brief Convert from I2C peripheral to number
* @param[in] I2Cx: I2C peripheral selected, should be:
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @return I2C number, could be: 0..2
*********************************************************************/
static LPC_I2C_TypeDef* I2C_GetPointer(en_I2C_unitId compId)
{
LPC_I2C_TypeDef* pI2C;
switch (compId)
{
case I2C_0:
pI2C = LPC_I2C0;
break;
case I2C_1:
pI2C = LPC_I2C1;
break;
case I2C_2:
pI2C = LPC_I2C2;
break;
default:
pI2C = NULL;
break;
}
return pI2C;
}
/********************************************************************//**
* @brief Convert from I2C peripheral to number
* @param[in] I2Cx: I2C peripheral selected, should be:
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @return I2C number, could be: 0..2
*********************************************************************/
static int32_t I2C_getNum(LPC_I2C_TypeDef *I2Cx)
{
if (I2Cx == LPC_I2C0)
{
return (0);
}
else if (I2Cx == LPC_I2C1)
{
return (1);
}
else if (I2Cx == LPC_I2C2)
{
return (2);
}
return (-1);
}
/********************************************************************//**
* @brief Generate a start condition on I2C bus (in master mode only)
* @param[in] I2Cx: I2C peripheral selected, should be:
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @return value of I2C status register after generate a start condition
*********************************************************************/
static uint32_t I2C_Start (LPC_I2C_TypeDef *I2Cx)
{
I2Cx->CONCLR = I2C_I2CONCLR_SIC;
I2Cx->CONSET = I2C_I2CONSET_STA;
// Wait for complete
while (!(I2Cx->CONSET & I2C_I2CONSET_SI));
I2Cx->CONCLR = I2C_I2CONCLR_STAC;
return (I2Cx->STAT & I2C_STAT_CODE_BITMASK);
}
/********************************************************************//**
* @brief Generate a stop condition on I2C bus (in master mode only)
* @param[in] I2Cx: I2C peripheral selected, should be:
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @return None
*********************************************************************/
static void I2C_Stop (LPC_I2C_TypeDef *I2Cx)
{
/* Make sure start bit is not active */
if (I2Cx->CONSET & I2C_I2CONSET_STA)
{
I2Cx->CONCLR = I2C_I2CONCLR_STAC;
}
I2Cx->CONSET = I2C_I2CONSET_STO;
I2Cx->CONCLR = I2C_I2CONCLR_SIC;
}
/********************************************************************//**
* @brief Send a byte
* @param[in] I2Cx: I2C peripheral selected, should be:
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @param[in] databyte: number of byte
* @return value of I2C status register after sending
*********************************************************************/
static uint32_t I2C_SendByte (LPC_I2C_TypeDef *I2Cx, uint8_t databyte)
{
/* Make sure start bit is not active */
if (I2Cx->CONSET & I2C_I2CONSET_STA)
{
I2Cx->CONCLR = I2C_I2CONCLR_STAC;
}
I2Cx->DAT = databyte & I2C_I2DAT_BITMASK;
I2Cx->CONCLR = I2C_I2CONCLR_SIC;
while (!(I2Cx->CONSET & I2C_I2CONSET_SI));
return (I2Cx->STAT & I2C_STAT_CODE_BITMASK);
}
/********************************************************************//**
* @brief Get a byte
* @param[in] I2Cx: I2C peripheral selected, should be:
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @param[out] retdat pointer to return data
* @param[in] ack assert acknowledge or not, should be: TRUE/FALSE
* @return value of I2C status register after sending
*********************************************************************/
static uint32_t I2C_GetByte (LPC_I2C_TypeDef *I2Cx, uint8_t *retdat, Bool ack)
{
if (ack == TRUE)
{
I2Cx->CONSET = I2C_I2CONSET_AA;
}
else
{
I2Cx->CONCLR = I2C_I2CONCLR_AAC;
}
I2Cx->CONCLR = I2C_I2CONCLR_SIC;
while (!(I2Cx->CONSET & I2C_I2CONSET_SI));
*retdat = (uint8_t) (I2Cx->DAT & I2C_I2DAT_BITMASK);
return (I2Cx->STAT & I2C_STAT_CODE_BITMASK);
}
/*********************************************************************//**
* @brief Setup clock rate for I2C peripheral
* @param[in] I2Cx I2C peripheral selected, should be:
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @param[in] target_clock : clock of SSP (Hz)
* @return None
***********************************************************************/
static void I2C_SetClock (LPC_I2C_TypeDef *I2Cx, uint32_t target_clock)
{
uint32_t temp;
temp = CLKPWR_GetCLK(CLKPWR_CLKTYPE_PER) / target_clock;
/* Set the I2C clock value to register */
I2Cx->SCLH = (uint32_t)(temp / 2);
I2Cx->SCLL = (uint32_t)(temp - I2Cx->SCLH);
}
/* End of Private Functions --------------------------------------------------- */
/* Public Functions ----------------------------------------------------------- */
/** @addtogroup I2C_Public_Functions
* @{
*/
/********************************************************************//**
* @brief Initializes the I2Cx peripheral with specified parameter.
* @param[in] I2Cx I2C peripheral selected, should be
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @param[in] clockrate Target clock rate value to initialized I2C
* peripheral (Hz)
* @return None
*********************************************************************/
void I2C_Init(uint8_t i2cId, uint32_t clockrate)
{
uint32_t clkSetting, clkRate;
LPC_I2C_TypeDef* I2Cx = I2C_GetPointer(i2cId);
switch (i2cId)
{
case I2C_0:
clkSetting = CLKPWR_PCONP_PCI2C0;
break;
case I2C_1:
clkSetting = CLKPWR_PCONP_PCI2C1;
break;
case I2C_2:
clkSetting = CLKPWR_PCONP_PCI2C2;
break;
default:
return;
}
CLKPWR_ConfigPPWR (clkSetting, ENABLE);
/* Set clock rate */
clkRate= CLKPWR_GetCLK(CLKPWR_CLKTYPE_PER) / clockrate;
/* Set the I2C clock value to register */
I2Cx->SCLH = (uint32_t)(clkRate / 2);
I2Cx->SCLL = (uint32_t)(clkRate - I2Cx->SCLH);
/* Set I2C operation to default */
I2Cx->CONCLR = (I2C_I2CONCLR_AAC | I2C_I2CONCLR_STAC | I2C_I2CONCLR_I2ENC);
}
/*********************************************************************//**
* @brief De-initializes the I2C peripheral registers to their
* default reset values.
* @param[in] I2Cx I2C peripheral selected, should be
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @return None
**********************************************************************/
void I2C_DeInit(uint8_t i2cId)
{
uint32_t clkSetting;
LPC_I2C_TypeDef* I2Cx = I2C_GetPointer(i2cId);
/* Disable I2C control */
I2Cx->CONCLR = I2C_I2CONCLR_I2ENC;
switch (i2cId)
{
case I2C_0:
clkSetting = CLKPWR_PCONP_PCI2C0;
break;
case I2C_1:
clkSetting = CLKPWR_PCONP_PCI2C1;
break;
case I2C_2:
clkSetting = CLKPWR_PCONP_PCI2C2;
break;
default:
return;
}
CLKPWR_ConfigPPWR (clkSetting, DISABLE);
}
/*********************************************************************//**
* @brief Enable or disable I2C peripheral's operation
* @param[in] I2Cx I2C peripheral selected, should be
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @param[in] NewState New State of I2Cx peripheral's operation
* @return none
**********************************************************************/
void I2C_Cmd(uint8_t i2cId, FunctionalState NewState)
{
LPC_I2C_TypeDef* I2Cx = I2C_GetPointer(i2cId);
if (NewState == ENABLE)
{
I2Cx->CONSET = I2C_I2CONSET_I2EN;
}
else
{
I2Cx->CONCLR = I2C_I2CONCLR_I2ENC;
}
}
/*********************************************************************//**
* @brief Enable/Disable interrupt for I2C peripheral
* @param[in] I2Cx I2C peripheral selected, should be:
* - LPC_I2C0
* - LPC_I2C1
* - LPC_I2C2
* @param[in] NewState New State of I2C peripheral interrupt in NVIC core
* should be:
* - ENABLE: enable interrupt for this I2C peripheral
* - DISABLE: disable interrupt for this I2C peripheral
* @return None
**********************************************************************/
void I2C_IntCmd (uint8_t i2cId, Bool NewState)
{
IRQn_Type irq;
switch (i2cId)
{
case I2C_0:
irq = I2C0_IRQn;
break;
case I2C_1:
irq = I2C1_IRQn;
break;
case I2C_2:
irq = I2C2_IRQn;
break;
default:
return;
}
if (NewState)
{
NVIC_EnableIRQ(irq);
}
else
{
NVIC_DisableIRQ(irq);
}
return;
}
/*********************************************************************//**
* @brief General Master Interrupt handler for I2C peripheral
* @param[in] I2Cx I2C peripheral selected, should be:
* - LPC_I2C
* - LPC_I2C1
* - LPC_I2C2
* @return None
**********************************************************************/
void I2C_MasterHandler(uint8_t i2cId)
{
LPC_I2C_TypeDef* I2Cx = I2C_GetPointer(i2cId);
uint8_t returnCode;
I2C_M_SETUP_Type *txrx_setup;
txrx_setup = (I2C_M_SETUP_Type *) i2cdat[i2cId].txrx_setup;
returnCode = (I2Cx->STAT & I2C_STAT_CODE_BITMASK);
// Save current status
txrx_setup->status = returnCode;
// there's no relevant information
if (returnCode == I2C_I2STAT_NO_INF)
{
I2Cx->CONCLR = I2C_I2CONCLR_SIC;
return;
}
/* ----------------------------- TRANSMIT PHASE --------------------------*/
if (i2cdat[i2cId].dir == 0)
{
switch (returnCode)
{
/* A start/repeat start condition has been transmitted -------------------*/
case I2C_I2STAT_M_TX_START:
case I2C_I2STAT_M_TX_RESTART:
I2Cx->CONCLR = I2C_I2CONCLR_STAC;
/*
* If there's any transmit data, then start to
* send SLA+W right now, otherwise check whether if there's
* any receive data for next state.
*/
if ((txrx_setup->tx_data != NULL) && (txrx_setup->tx_length != 0))
{
I2Cx->DAT = (txrx_setup->sl_addr7bit << 1);
I2Cx->CONCLR = I2C_I2CONCLR_SIC;
}
else
{
goto next_stage;
}
break;
/* SLA+W has been transmitted, ACK has been received ----------------------*/
case I2C_I2STAT_M_TX_SLAW_ACK:
/* Data has been transmitted, ACK has been received */
case I2C_I2STAT_M_TX_DAT_ACK:
/* Send more data */
if ((txrx_setup->tx_count < txrx_setup->tx_length) && (txrx_setup->tx_data != NULL))
{
I2Cx->DAT = *(uint8_t *)(txrx_setup->tx_data + txrx_setup->tx_count);
txrx_setup->tx_count++;
I2Cx->CONCLR = I2C_I2CONCLR_SIC;
}
// no more data, switch to next stage
else
{
next_stage:
// change direction
i2cdat[i2cId].dir = 1;
// Check if any data to receive
if ((txrx_setup->rx_length != 0) && (txrx_setup->rx_data != NULL))
{
// check whether if we need to issue an repeat start
if ((txrx_setup->tx_length != 0) && (txrx_setup->tx_data != NULL))
{
// Send out an repeat start command
I2Cx->CONSET = I2C_I2CONSET_STA;
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