LPCOpen Platform for LPC112X microcontrollers  112X
LPCOpen Platform for the NXP LPC112X family of Microcontrollers
Data Structures | Macros | Functions | Variables
i2c_112x.c File Reference
#include "chip.h"

Go to the source code of this file.

Data Structures

struct  i2c_interface
 
struct  i2c_slave_interface
 

Macros

#define I2C_CON_FLAGS   (I2C_CON_AA | I2C_CON_SI | I2C_CON_STO | I2C_CON_STA)
 
#define LPC_I2Cx(id)   ((i2c[id].ip))
 
#define SLAVE_ACTIVE(iic)   (((iic)->flags & 0xFF00) != 0)
 

Functions

STATIC INLINE void enableClk (I2C_ID_T id)
 
STATIC INLINE void disableClk (I2C_ID_T id)
 
STATIC INLINE uint32_t getClkRate (I2C_ID_T id)
 
STATIC INLINE void startMasterXfer (LPC_I2C_T *pI2C)
 
STATIC INLINE void startSlaverXfer (LPC_I2C_T *pI2C)
 
STATIC INLINE int isI2CBusFree (LPC_I2C_T *pI2C)
 
STATIC INLINE int getCurState (LPC_I2C_T *pI2C)
 
STATIC INLINE int isMasterState (LPC_I2C_T *pI2C)
 
STATIC void setSlaveAddr (LPC_I2C_T *pI2C, I2C_SLAVE_ID sid, uint8_t addr, uint8_t mask)
 
STATIC int isSlaveAddrMatching (uint8_t addr1, uint8_t addr2, uint8_t mask)
 
STATIC I2C_SLAVE_ID lookupSlaveIndex (LPC_I2C_T *pI2C, uint8_t slaveAddr)
 
int handleMasterXferState (LPC_I2C_T *pI2C, I2C_XFER_T *xfer)
 
I2C_SLAVE_ID getSlaveIndex (LPC_I2C_T *pI2C)
 
int handleSlaveXferState (LPC_I2C_T *pI2C, I2C_XFER_T *xfer)
 
void Chip_I2C_EventHandler (I2C_ID_T id, I2C_EVENT_T event)
 Default event handler for interrupt base operation. More...
 
void Chip_I2C_EventHandlerPolling (I2C_ID_T id, I2C_EVENT_T event)
 Default event handler for polling operation. More...
 
void Chip_I2C_Init (I2C_ID_T id)
 Initializes the LPC_I2C peripheral with specified parameter. More...
 
void Chip_I2C_DeInit (I2C_ID_T id)
 De-initializes the I2C peripheral registers to their default reset values. More...
 
void Chip_I2C_SetClockRate (I2C_ID_T id, uint32_t clockrate)
 Set up clock rate for LPC_I2C peripheral. More...
 
uint32_t Chip_I2C_GetClockRate (I2C_ID_T id)
 Get current clock rate for LPC_I2C peripheral. More...
 
int Chip_I2C_SetMasterEventHandler (I2C_ID_T id, I2C_EVENTHANDLER_T event)
 Set function that must handle I2C events. More...
 
I2C_EVENTHANDLER_T Chip_I2C_GetMasterEventHandler (I2C_ID_T id)
 Get pointer to current function handling the events. More...
 
int Chip_I2C_MasterTransfer (I2C_ID_T id, I2C_XFER_T *xfer)
 Transmit and Receive data in master mode. More...
 
int Chip_I2C_MasterSend (I2C_ID_T id, uint8_t slaveAddr, const uint8_t *buff, uint8_t len)
 Transmit data to I2C slave using I2C Master mode. More...
 
int Chip_I2C_MasterCmdRead (I2C_ID_T id, uint8_t slaveAddr, uint8_t cmd, uint8_t *buff, int len)
 Transfer a command to slave and receive data from slave after a repeated start. More...
 
int Chip_I2C_MasterRead (I2C_ID_T id, uint8_t slaveAddr, uint8_t *buff, int len)
 Set function that must handle I2C events. More...
 
int Chip_I2C_IsMasterActive (I2C_ID_T id)
 Checks if master xfer in progress. More...
 
void Chip_I2C_MasterStateHandler (I2C_ID_T id)
 I2C Master transfer state change handler. More...
 
void Chip_I2C_SlaveSetup (I2C_ID_T id, I2C_SLAVE_ID sid, I2C_XFER_T *xfer, I2C_EVENTHANDLER_T event, uint8_t addrMask)
 Setup a slave I2C device. More...
 
void Chip_I2C_SlaveStateHandler (I2C_ID_T id)
 I2C Slave event handler. More...
 
void Chip_I2C_Disable (I2C_ID_T id)
 Disable I2C peripheral's operation. More...
 
int Chip_I2C_IsStateChanged (I2C_ID_T id)
 I2C peripheral state change checking. More...
 

Variables

static struct i2c_interface i2c [I2C_NUM_INTERFACE]
 
static struct i2c_slave_interface i2c_slave [I2C_NUM_INTERFACE][I2C_SLAVE_NUM_INTERFACE]
 

Macro Definition Documentation

#define I2C_CON_FLAGS   (I2C_CON_AA | I2C_CON_SI | I2C_CON_STO | I2C_CON_STA)

Definition at line 39 of file i2c_112x.c.

#define LPC_I2Cx (   id)    ((i2c[id].ip))

Definition at line 40 of file i2c_112x.c.

#define SLAVE_ACTIVE (   iic)    (((iic)->flags & 0xFF00) != 0)

Definition at line 41 of file i2c_112x.c.

Function Documentation

void Chip_I2C_DeInit ( I2C_ID_T  id)

De-initializes the I2C peripheral registers to their default reset values.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
Returns
Nothing

Definition at line 374 of file i2c_112x.c.

void Chip_I2C_Disable ( I2C_ID_T  id)

Disable I2C peripheral's operation.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
Returns
Nothing

Definition at line 543 of file i2c_112x.c.

void Chip_I2C_EventHandler ( I2C_ID_T  id,
I2C_EVENT_T  event 
)

Default event handler for interrupt base operation.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
event: Event ID of the event that called the function
Returns
Nothing

Definition at line 326 of file i2c_112x.c.

void Chip_I2C_EventHandlerPolling ( I2C_ID_T  id,
I2C_EVENT_T  event 
)

Default event handler for polling operation.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
event: Event ID of the event that called the function
Returns
Nothing

Definition at line 342 of file i2c_112x.c.

uint32_t Chip_I2C_GetClockRate ( I2C_ID_T  id)

Get current clock rate for LPC_I2C peripheral.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
Returns
The current I2C peripheral clock rate

Definition at line 393 of file i2c_112x.c.

I2C_EVENTHANDLER_T Chip_I2C_GetMasterEventHandler ( I2C_ID_T  id)

Get pointer to current function handling the events.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
Returns
Pointer to function handing events of I2C

Definition at line 409 of file i2c_112x.c.

void Chip_I2C_Init ( I2C_ID_T  id)

Initializes the LPC_I2C peripheral with specified parameter.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
Returns
Nothing

Definition at line 362 of file i2c_112x.c.

int Chip_I2C_IsMasterActive ( I2C_ID_T  id)

Checks if master xfer in progress.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
Returns
1 if master xfer in progress 0 otherwise
Note
This API is generally used in interrupt handler of the application to decide whether to call master state handler or to call slave state handler

Definition at line 480 of file i2c_112x.c.

int Chip_I2C_IsStateChanged ( I2C_ID_T  id)

I2C peripheral state change checking.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
Returns
1 if I2C peripheral id has changed its state, 0 if there is no state change
Note
This function must be used by the application when the polling has to be done based on state change.

Definition at line 549 of file i2c_112x.c.

int Chip_I2C_MasterCmdRead ( I2C_ID_T  id,
uint8_t  slaveAddr,
uint8_t  cmd,
uint8_t *  buff,
int  len 
)

Transfer a command to slave and receive data from slave after a repeated start.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
slaveAddr: Slave address of the I2C device
cmd: Command (Address/Register) to be written
buff: Pointer to memory that will hold the data received
len: Number of bytes to receive
Returns
Number of bytes successfully received

Definition at line 456 of file i2c_112x.c.

int Chip_I2C_MasterRead ( I2C_ID_T  id,
uint8_t  slaveAddr,
uint8_t *  buff,
int  len 
)

Set function that must handle I2C events.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
slaveAddr: Slave address from which data be read
buff: Pointer to memory where data read be stored
len: Number of bytes to read from slave
Returns
Number of bytes read successfully

Definition at line 469 of file i2c_112x.c.

int Chip_I2C_MasterSend ( I2C_ID_T  id,
uint8_t  slaveAddr,
const uint8_t *  buff,
uint8_t  len 
)

Transmit data to I2C slave using I2C Master mode.

Parameters
id: I2C peripheral ID (I2C0, I2C1 .. etc)
slaveAddr: Slave address to which the data be written
buff: Pointer to buffer having the array of data
len: Number of bytes to be transfered from buff
Returns
Number of bytes successfully transfered

Definition at line 443 of file i2c_112x.c.

void Chip_I2C_MasterStateHandler ( I2C_ID_T  id)

I2C Master transfer state change handler.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
Returns
Nothing
Note
Usually called from the appropriate Interrupt handler

Definition at line 486 of file i2c_112x.c.

int Chip_I2C_MasterTransfer ( I2C_ID_T  id,
I2C_XFER_T xfer 
)

Transmit and Receive data in master mode.

Parameters
id: I2C peripheral selected (I2C0, I2C1 etc)
xfer: Pointer to a I2C_XFER_T structure see notes below
Returns
Any of I2C_STATUS_T values, xfer->txSz will have number of bytes not sent due to error, xfer->rxSz will have the number of bytes yet to be received.
Note
The parameter xfer should have its member slaveAddr initialized to the 7-Bit slave address to which the master will do the xfer, Bit0 to bit6 should have the address and Bit8 is ignored. During the transfer no code (like event handler) must change the content of the memory pointed to by xfer. The member of xfer, txBuff and txSz be initialized to the memory from which the I2C must pick the data to be transfered to slave and the number of bytes to send respectively, similarly rxBuff and rxSz must have pointer to memroy where data received from slave be stored and the number of data to get from slave respectilvely.

Definition at line 415 of file i2c_112x.c.

void Chip_I2C_SetClockRate ( I2C_ID_T  id,
uint32_t  clockrate 
)

Set up clock rate for LPC_I2C peripheral.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
clockrate: Target clock rate value to initialized I2C peripheral (Hz)
Returns
Nothing
Note
Parameter clockrate for I2C0 should be from 1000 up to 1000000 (1 KHz to 1 MHz), as I2C0 support Fast Mode Plus. If the clockrate is more than 400 KHz (Fast Plus Mode) Board_I2C_EnableFastPlus() must be called prior to calling this function.

Definition at line 383 of file i2c_112x.c.

int Chip_I2C_SetMasterEventHandler ( I2C_ID_T  id,
I2C_EVENTHANDLER_T  event 
)

Set function that must handle I2C events.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
event: Pointer to function that will handle the event (Should not be NULL)
Returns
1 when successful, 0 when a transfer is on going with its own event handler

Definition at line 399 of file i2c_112x.c.

void Chip_I2C_SlaveSetup ( I2C_ID_T  id,
I2C_SLAVE_ID  sid,
I2C_XFER_T xfer,
I2C_EVENTHANDLER_T  event,
uint8_t  addrMask 
)

Setup a slave I2C device.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
sid: I2C Slave peripheral ID (I2C_SLAVE_0, I2C_SLAVE_1 etc)
xfer: Pointer to transfer structure (see note below for more info)
event: Event handler for slave transfers
addrMask: Address mask to use along with slave address (see notes below for more info)
Returns
Nothing
Note
Parameter xfer should point to a valid I2C_XFER_T structure object and must have slaveAddr initialized with 7bit Slave address (From Bit1 to Bit7), Bit0 when set enables general call handling, slaveAddr along with addrMask will be used to match the slave address. rxBuff and txBuff must point to valid buffers where slave can receive or send the data from, size of which will be provided by rxSz and txSz respectively. Function pointed to by event will be called for the following events I2C_EVENT_SLAVE_RX (One byte of data received successfully from the master and stored inside memory pointed by xfer->rxBuff, incremented the pointer and decremented the xfer->rxSz), I2C_EVENT_SLAVE_TX (One byte of data from xfer->txBuff was sent to master successfully, incremented the pointer and decremented xfer->txSz), I2C_EVENT_DONE (Master is done doing its transfers with the slave).

Bit-0 of the parameter addrMask is reserved and should always be 0. Any bit (BIT1 to BIT7) set in addrMask will make the corresponding bit in xfer->slaveAddr as don't care. Thit is, if xfer->slaveAddr is (0x10 << 1) and addrMask is (0x03 << 1) then 0x10, 0x11, 0x12, 0x13 will all be considered as valid slave addresses for the registered slave. Upon receving any event xfer->slaveAddr (BIT1 to BIT7) will hold the actual address which was received from master.

General Call Handling
Slave can receive data from master using general call address (0x00). General call handling must be setup as given below
  • Call Chip_I2C_SlaveSetup() with argument sid as I2C_SLAVE_GENERAL
    • xfer->slaveAddr ignored, argument addrMask ignored
    • function provided by event will registered to be called when slave received data using addr 0x00
    • xfer->rxBuff and xfer->rxSz should be valid in argument xfer
  • To handle General Call only (No other slaves are configured)
    • Call Chip_I2C_SlaveSetup() with sid as I2C_SLAVE_X (X=0,1,2,3)
    • setup xfer with slaveAddr member set to 0, event is ignored hence can be NULL
    • provide addrMask (typically 0, if not you better be knowing what you are doing)
  • To handler General Call when other slave is active
    • Call Chip_I2C_SlaveSetup() with sid as I2C_SLAVE_X (X=0,1,2,3)
    • setup xfer with slaveAddr member set to 7-Bit Slave address [from Bit1 to 7]
    • Set Bit0 of xfer->slaveAddr as 1
    • Provide appropriate addrMask
    • Argument event must point to function, that handles events from actual slaveAddress and not the GC
Warning
If the slave has only one byte in its txBuff, once that byte is transfered to master the event handler will be called for event I2C_EVENT_DONE. If the master attempts to read more bytes in the same transfer then the slave hardware will send 0xFF to master till the end of transfer, event handler will not be called to notify this. For more info see section below

Last data handling in slave
If the user wants to implement a slave which will read a byte from a specific location over and over again whenever master reads the slave. If the user initializes the xfer->txBuff as the location to read the byte from and xfer->txSz as 1, then say, if master reads one byte; slave will send the byte read from xfer->txBuff and will call the event handler with I2C_EVENT_DONE. If the master attempts to read another byte instead of sending the byte read from xfer->txBuff the slave hardware will send 0xFF and no event will occur. To handle this issue, slave should set xfer->txSz to 2, in which case when master reads the byte event handler will be called with I2C_EVENT_SLAVE_TX, in which the slave implementation can reset the buffer and size back to original location (i.e, xfer->txBuff–, xfer->txSz++), if the master reads another byte in the same transfer, byte read from xfer->txBuff will be sent and I2C_EVENT_SLAVE_TX will be called again, and the process repeats.

Definition at line 494 of file i2c_112x.c.

void Chip_I2C_SlaveStateHandler ( I2C_ID_T  id)

I2C Slave event handler.

Parameters
id: I2C peripheral ID (I2C0, I2C1 ... etc)
Returns
Nothing

Definition at line 517 of file i2c_112x.c.

STATIC INLINE void disableClk ( I2C_ID_T  id)

Definition at line 80 of file i2c_112x.c.

STATIC INLINE void enableClk ( I2C_ID_T  id)

Definition at line 75 of file i2c_112x.c.

STATIC INLINE uint32_t getClkRate ( I2C_ID_T  id)

Definition at line 86 of file i2c_112x.c.

STATIC INLINE int getCurState ( LPC_I2C_T pI2C)

Definition at line 118 of file i2c_112x.c.

I2C_SLAVE_ID getSlaveIndex ( LPC_I2C_T pI2C)

Definition at line 243 of file i2c_112x.c.

int handleMasterXferState ( LPC_I2C_T pI2C,
I2C_XFER_T xfer 
)

Definition at line 174 of file i2c_112x.c.

int handleSlaveXferState ( LPC_I2C_T pI2C,
I2C_XFER_T xfer 
)

Definition at line 260 of file i2c_112x.c.

STATIC INLINE int isI2CBusFree ( LPC_I2C_T pI2C)

Definition at line 112 of file i2c_112x.c.

STATIC INLINE int isMasterState ( LPC_I2C_T pI2C)

Definition at line 124 of file i2c_112x.c.

STATIC int isSlaveAddrMatching ( uint8_t  addr1,
uint8_t  addr2,
uint8_t  mask 
)

Definition at line 144 of file i2c_112x.c.

STATIC I2C_SLAVE_ID lookupSlaveIndex ( LPC_I2C_T pI2C,
uint8_t  slaveAddr 
)

Definition at line 151 of file i2c_112x.c.

STATIC void setSlaveAddr ( LPC_I2C_T pI2C,
I2C_SLAVE_ID  sid,
uint8_t  addr,
uint8_t  mask 
)

Definition at line 130 of file i2c_112x.c.

STATIC INLINE void startMasterXfer ( LPC_I2C_T pI2C)

Definition at line 92 of file i2c_112x.c.

STATIC INLINE void startSlaverXfer ( LPC_I2C_T pI2C)

Definition at line 102 of file i2c_112x.c.

Variable Documentation

struct i2c_interface i2c[I2C_NUM_INTERFACE]
static
Initial value:

Definition at line 61 of file i2c_112x.c.

Definition at line 65 of file i2c_112x.c.