MCF5441x I2C

Functions
void	MultiChannel_I2CInit (int moduleNum=DEFAULT_I2C_MODULE, uint8_t slave_Addr=0x08, uint8_t freqdiv=0x3C)
	Initialize the I2C peripheral module.
uint8_t	MultiChannel_I2CSendBuf (int moduleNum, uint8_t addr, puint8_t buf, int num, bool stop=true)
	Send a buffer of bytes to an I2C device.
uint8_t	MultiChannel_I2CReadBuf (int moduleNum, uint8_t addr, puint8_t buf, int num, bool stop=true)
	Read a number of bytes from an I2C device and store in the specified buffer.
void	I2CMultiChannelResetPeripheral (int moduleNum)
	Reset the specified I2C peripheral module.
uint8_t	MultiChannel_I2CRestart (int moduleNum, uint8_t addr, bool Read_Not_Write, uint32_t ticks_to_wait=I2C_RX_TX_TIMEOUT)
	Restart communication with a I2C device.
uint8_t	MultiChannel_I2CStart (int moduleNum, uint8_t addr, bool Read_Not_Write, uint32_t ticks_to_wait=I2C_START_TIMEOUT)
	Send an I2C start to an I2C device to begin communication.
uint8_t	MultiChannel_I2CStop (int moduleNum=DEFAULT_I2C_MODULE, uint32_t ticks_to_wait=I2C_RX_TX_TIMEOUT)
	Issue an I2C stop terminate communication with an I2C device and release the bus.
uint8_t	MultiChannel_I2CSend (int moduleNum, uint8_t val, uint32_t ticks_to_wait=I2C_RX_TX_TIMEOUT)
	Send a single byte on the I2C bus.
uint8_t	MultiChannel_I2CRead (int moduleNum, puint8_t val, uint32_t ticks_to_wait=I2C_RX_TX_TIMEOUT)
	Read a single byte from the I2C bus.

Multichannel I2C Return Values
Function return values
#define	I2C_OK   (0)
	Last instruction terminated correctly.
#define	I2C_NEXT_WRITE_OK   (1)
	I2C bus is OK for a write.
#define	I2C_NEXT_READ_OK   (2)
	I2C bus is OK for a read.
#define	I2C_MASTER_OK   (3)
	I2C finished transmission but still owns but (need to stop or restart)
#define	I2C_TIMEOUT   (4)
	A timeout occurred while trying communicate on I2C bus.
#define	I2C_BUS_NOT_AVAIL   (5)
	A timeout occurred while trying gain I2C bus control.
#define	I2C_NOT_READY   (6)
	A read or write was attempted before I2C ready or during a slave transmission.
#define	I2C_LOST_ARB   (7)
	Lost arbitration during start.
#define	I2C_LOST_ARB_ADD   (8)
	Lost arbitration and then winner addressed our slave address.
#define	I2C_NO_LINK_RX_ACK   (9)
	We are in Master TX mode and received no ACK from slave device, possibly during start.

Multichannel I2C Macros
I2C Macros
#define	I2C_SR_BUSY   (((0x20 & I2C_SR) == 0x20))
	Bus is busy (bit 5 of I2SR)
#define	I2C_CR_SLAVE   (((0x20 & I2C_CR) == 0x00))
	Bus set as slave (bit 5 of I2CR)
#define	I2C_SR_ARB_LOST   (((0x10 & I2C_SR) == 0x10))
	Bus arbitration was lost (bit 4 of I2SR)
#define	I2C_SR_ADRES_AS_SLAVE   (((0x40 & I2C_SR) == 0x40))
	Addressed as a slave (bit 6 of I2SR)
#define	I2C_SR_SLAVE_TX   (((0x04 & I2C_SR) == 0x04))
	State of read/write bit of the received address command (bit 2 of I2SR)
#define	I2C_CR_TX   (((0x10 & I2C_CR) == 0x10))
	Configured for transmit (bit 4 of I2CR)
#define	I2C_SR_RX_ACK   (((0x01 & I2C_SR) == 0x00))
	Received a RX ACK after last transmit (bit 0 of I2SR)
#define	I2C_CR_RX_ACK   (((0x08 & I2C_CR) == 0x00))
	Configured to RX Ack.
#define	I2C_SET_NO_ACK   ((I2C_CR |= 0x08))
	Configure I2C module not to send a RX ACK (bit 3 of I2CR)
#define	I2C_SET_ACK   ((I2C_CR &= 0xF7))
	Configure I2C module to send a RX ACK (bit 3 of I2CR)
#define	I2C_SET_TX   ((I2C_CR |= 0x10))
	Configure I2C module to be in TX mode (bit 4 of I2CR)
#define	I2C_SET_RX   ((I2C_CR &= 0xEF))
	Configure I2C module to be in RX mode (bit 4 of I2CR)
#define	I2C_SET_REPEAT_START   ((I2C_CR |= 0x04))
	Configure I2C to send a repeated start signal.
#define	I2C_CLR_ARB_LOST   ((I2C_SR &= 0xEF))
	Clear Arbitration lost error condition.

Detailed Description

Supported platforms:

• MOD54415
• MOD54417
• NANO54415

• SB800EX

  The platforms have multiple I2C interfaces called "modules". The available I2C modules available on a particular platform are determined by the connector configuration of that platform. Available I2C module numbers are defined below. Since the processor pins are multiplexed with many other functions, the modules chosen are not sequential. The default module number is 0.

  I2C MODULE NUMBERS BY PLATFORM:

  • MOD5441x: 0, 1, 2, 4, 5.
  • NANO54415: 0, 1, 4, 5.

The most common I2C functions used are listed below. They automatically handle I2C start and stop conditions, as well as checking for I2C bus errors and recovery:

• MultiChannel_I2CInit ()
• MultiChannel_I2CSendBuf ()
• MultiChannel_I2CReadBuf ()
• I2CMultiChannelResetPeripheral()

Function Documentation

I2CMultiChannelResetPeripheral()

void I2CMultiChannelResetPeripheral

(

int

moduleNum

)

#include <multichanneli2c.h>

Reset the specified I2C peripheral module.

Clears all interrupts, I2C conditions, and releases the bus.

Parameters

moduleNum

I2C peripheral module number.

MultiChannel_I2CInit()

void MultiChannel_I2CInit	(	int	moduleNum = DEFAULT_I2C_MODULE,
		uint8_t	slave_Addr = 0x08,
		uint8_t	freqdiv = 0x3C )

#include <multichanneli2c.h>

Initialize the I2C peripheral module.

The frequency is based on the internal bus clock of the processor. The formula is: Freq = (250MHZ (sys clock)/2) / freqdiv to give max baud rate of the master mode I2C bus clock. Values for freqdiv are found in the i2fdr section of the NXP MCF5441x User Manual.

Parameters

moduleNum	I2C peripheral module number.
slave_Addr	I2C address of the module. If not specified, default value is 0x08.
freqdiv	I2C module frequency divider. If not specified, default value is 0x3C, which is the maximum value of 100KHz.

MultiChannel_I2CRead()

uint8_t MultiChannel_I2CRead	(	int	moduleNum,
		puint8_t	val,
		uint32_t	ticks_to_wait = I2C_RX_TX_TIMEOUT )

#include <multichanneli2c.h>

Read a single byte from the I2C bus.

Reads a single byte from the I2C bus and stores it in val. A start or restart must have been previously issued to become the bus master, and a stop must be issued to release the bus when you are finished reading the desired number of bytes.

Does not handle no Ack of last byte, which needs to have a I2C_SET_NO_ACK called before the last read.

Parameters

moduleNum	I2C peripheral module number.
val	Location to store the byte read.
ticks_to_wait	Amount of time to wait for a start transmission to complete, specified as system time ticks. The TICKS_PER_SECOND macro can be used with a multiplier or dividor. Includes the time to receive an ack from the I2C device. If not specified, the default time of I2C_RX_TX_TIMEOUT will be used.

Returns

The state of the I2C bus: I2C Return Values

MultiChannel_I2CReadBuf()

uint8_t MultiChannel_I2CReadBuf	(	int	moduleNum,
		uint8_t	addr,
		puint8_t	buf,
		int	num,
		bool	stop = true )

#include <multichanneli2c.h>

Read a number of bytes from an I2C device and store in the specified buffer.

Sends an I2C start, reads the specified number of bytes into buf, and and finishes with our without an I2C stop (default is stop). If a stop is not issued, for purposes such as a restart, a stop must be called manually.

Parameters

moduleNum	I2C peripheral module number.
addr	I2C device address.
buf	The buffer to store the data.
num	The number of bytes to read.
stop	Send a stop signal at the end of the transaction. If not specified, the default value is true.

Returns

The state of the I2C bus: I2C Return Values

MultiChannel_I2CRestart()

uint8_t MultiChannel_I2CRestart	(	int	moduleNum,
		uint8_t	addr,
		bool	Read_Not_Write,
		uint32_t	ticks_to_wait = I2C_RX_TX_TIMEOUT )

#include <multichanneli2c.h>

Restart communication with a I2C device.

Restarts communication with an I2C device after completion of a read or write command in which a stop was not issued. Enables communicate on bus again without giving up control as the I2C bus master.

Parameters

moduleNum	I2C peripheral module number.
addr	I2C device address.
Read_Not_Write	Specifies the next bus operation: true = read, false = write.
ticks_to_wait	Amount of time to wait for a start transmission to complete, specified as system time ticks. The TICKS_PER_SECOND macro can be used with a multiplier or dividor. Includes the time to receive an ack from the I2C device. If not specified, the default time of I2C_RX_TX_TIMEOUT will be used.

Returns

The state of the I2C bus: I2C Return Values

MultiChannel_I2CSend()

uint8_t MultiChannel_I2CSend	(	int	moduleNum,
		uint8_t	val,
		uint32_t	ticks_to_wait = I2C_RX_TX_TIMEOUT )

#include <multichanneli2c.h>

Send a single byte on the I2C bus.

Sends a single byte on the I2C bus. A start or restart must have been previously issued to become the bus master, and a stop must be issued to release the bus when you are finished with writing the desired number of bytes.

Parameters

moduleNum	I2C peripheral module number.
val	Byte to send
ticks_to_wait	Amount of time to wait for a start transmission to complete, specified as system time ticks. The TICKS_PER_SECOND macro can be used with a multiplier or dividor. Includes the time to receive an ack from the I2C device. If not specified, the default time of I2C_RX_TX_TIMEOUT will be used.

Returns

The state of the I2C bus: I2C Return Values

MultiChannel_I2CSendBuf()

uint8_t MultiChannel_I2CSendBuf	(	int	moduleNum,
		uint8_t	addr,
		puint8_t	buf,
		int	num,
		bool	stop = true )

#include <multichanneli2c.h>

Send a buffer of bytes to an I2C device.

Sends an I2C start, the bytes in buf, and and finishes with our without an I2C stop (default is stop). If a stop is not issued, for purposes such as a restart, a stop must be called manually.

Parameters

moduleNum	I2C peripheral module number.
addr	I2C device address.
buf	The buffer to send.
num	The number of bytes in the buffer.
stop	Send a stop signal at the end of transmission. If not specified, the default value is true.

Returns

The state of the I2C bus: I2C Return Values

MultiChannel_I2CStart()

uint8_t MultiChannel_I2CStart	(	int	moduleNum,
		uint8_t	addr,
		bool	Read_Not_Write,
		uint32_t	ticks_to_wait = I2C_START_TIMEOUT )

#include <multichanneli2c.h>

Send an I2C start to an I2C device to begin communication.

Restarts communication with an I2C device after completion of a read or write command in which a stop was not issued. Enables communicate on bus again without giving up control as the I2C bus master.

Parameters

moduleNum	I2C peripheral module number.
addr	I2C device address.
Read_Not_Write	Specifies the next bus operation: true = read, false = write.
ticks_to_wait	Amount of time to wait for a start transmission to complete, specified as system time ticks. The TICKS_PER_SECOND macro can be used with a multiplier or dividor. Includes the time to receive an ack from the I2C device. If not specified, the default time of I2C_START_TIMEOUT will be used.

Returns

The state of the I2C bus: I2C Return Values

MultiChannel_I2CStop()

uint8_t MultiChannel_I2CStop	(	int	moduleNum = DEFAULT_I2C_MODULE,
		uint32_t	ticks_to_wait = I2C_RX_TX_TIMEOUT )

#include <multichanneli2c.h>

Issue an I2C stop terminate communication with an I2C device and release the bus.

Terminate any communication and release the I2C bus.

Parameters

moduleNum	I2C peripheral module number.
ticks_to_wait	Amount of time to wait for a start transmission to complete, specified as system time ticks. The TICKS_PER_SECOND macro can be used with a multiplier or dividor. Includes the time to receive an ack from the I2C device. If not specified, the default time of I2C_RX_TX_TIMEOUT will be used.

Returns

The state of the I2C bus: I2C Return Values