I2CDevice Class Reference

I2C Device Class (recommended) More...

#include <i2c.h>

Public Member Functions
	I2CDevice (I2C &pInterface, uint8_t deviceAddress, uint8_t numAddressBytes=1)
	Initialize the I2C module.
uint8_t	getI2CAddress ()
	Get device's I2C address.
void	setup (uint32_t busSpeed)
	Setup the I2C peripheral module.
void	resetBus ()
	Reset the I2C bus.
I2C::Result_t	writeReg8 (uint32_t reg, uint8_t data)
	Write an 8-bit value to an I2C slave device register.
I2C::Result_t	readReg8 (uint32_t reg, uint8_t &data)
	Read an 8-bit value form an I2C slave device register.
I2C::Result_t	writeRegN (uint32_t reg, const uint8_t *buf, uint32_t blen)
	Write a number of 8-bit values to an I2C slave to the specified register address.
I2C::Result_t	readRegN (uint32_t reg, uint8_t *buf, uint32_t blen)
	Read a number of 8-bit values from an I2C slave at the specified register address.

Detailed Description

I2C Device Class (recommended)

For I2C communication, you can choose the I2CDevice class, the I2C class, or the WireIntf class. The recommended interface is the I2CDevice class.

For example, to create an object for an analog to digital converter:

I2CDevice AdcDevice(i2c[I2C_MODULE_NUM], I2C_ADC_ADDRESS); 

To read a 16 bit value:

uint8_t I2CStat = AdcDevice.readRegN(0x00, buf, 2); 

Constructor & Destructor Documentation

I2CDevice()

I2CDevice::I2CDevice ( I2C & pInterface, uint8_t deviceAddress, uint8_t numAddressBytes = 1 )

inline

Initialize the I2C module.

Parameters

pInterface	Pointer to the I2C interface to use. This will normally be one of the preallocated I2C modules in the i2c[] array: i2c[0] (default), i2c[1] or i2c[2].
deviceAddress	I2C device address
numAddressBytes	Number of address bytes to send to specify the register or address to access for a read or write operation. Refer to your I2C device data sheet to determine the correct number. The I2C address range is 24-bits maximum (3 bytes). The default value is 1 byte, representing an address range of 0 to 255.

Member Function Documentation

getI2CAddress()

uint8_t I2CDevice::getI2CAddress ( )

inline

Get device's I2C address.

Note that the return address will be just the I2C address bits, not including the read/write bit. If your device data sheet specifies the address byte to include the read/write bit, that value would be this address left shifted by 1. For example, if a device data sheet specifies the address as 0xA2 and includes the read/write bit, the actual address would be 0x51.

Returns

The device's I2C address

readReg8()

I2C::Result_t I2CDevice::readReg8 ( uint32_t reg, uint8_t & data )

inline

Read an 8-bit value form an I2C slave device register.

Parameters

reg	Register address to read
data	Reference to variable in which to store the register data

Returns

I2C::Result_t

readRegN()

I2C::Result_t I2CDevice::readRegN ( uint32_t reg, uint8_t * buf, uint32_t blen )

inline

Read a number of 8-bit values from an I2C slave at the specified register address.

Parameters

reg	Register address to read
*buf	Pointer to buffer to store received data
blen	Number of bytes to read

Returns

I2C::Result_t

setup()

void I2CDevice::setup ( uint32_t busSpeed )

inline

Setup the I2C peripheral module.

Parameters

busSpeed

Target bus speed. It the specified speed cannot be achieved, a lower bus speed may be enabled.

writeReg8()

I2C::Result_t I2CDevice::writeReg8 ( uint32_t reg, uint8_t data )

inline

Write an 8-bit value to an I2C slave device register.

Parameters

reg	Register address to write
data	Data to write to register

Returns

I2C::Result_t

writeRegN()

I2C::Result_t I2CDevice::writeRegN ( uint32_t reg, const uint8_t * buf, uint32_t blen )

inline

Write a number of 8-bit values to an I2C slave to the specified register address.

Executing this function will send the following: a start bit, the slave device address and read/write bit, the 8-bit data bytes, and finally a stop bit. Note that the address is not incremented with each 8-bit data value.

Parameters

reg	Register address to write
*buf	Pointer to buffer containing data to write
blen	Number of bytes to write

Returns

I2C::Result_t

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The documentation for this class was generated from the following file:

• i2c.h