Erriez MCP23017 I2C IO-Expander class. More...

#include <ErriezMCP23017.h>

Public Member Functions
	ErriezMCP23017 (uint8_t i2cAddress=MCP23017_I2C_ADDRESS, TwoWire *twoWire=&Wire)
	ErriezMCP23017 Constructor. More...

bool	begin (bool reset=true)
	Initialize MCP23017. More...

void	pinMode (uint8_t pin, uint8_t mode)
	Set direction of a single pin. More...

void	digitalWrite (uint8_t pin, uint8_t level)
	Set state of a single pin. More...

int	digitalRead (uint8_t pin)
	Get state of a single pin. More...

void	setPortDirection (uint16_t outputPins)
	Set PORT direction all pins. More...

uint16_t	getPortDirection ()
	Get PORT direction all pins. More...

void	setPortPullup (uint16_t pullupPins)
	Set PORT pullup all pins. More...

uint16_t	getPortPullup ()
	Get PORT pullup all pins. More...

void	pinWrite (uint8_t pin, bool level)
	Set pin state. More...

void	pinToggle (uint8_t pin)
	Toggle state of a single pin (only for output pins) More...

bool	pinRead (uint8_t pin)
	Read state of a single pin (input and output pins) More...

void	portWrite (uint16_t value)
	Set all pin states. More...

void	portToggle (uint16_t value)
	Toggle pin states (output pins only) More...

void	portMask (uint16_t maskSet, uint16_t maskClear)
	Clear and set pin states. More...

uint16_t	portRead ()
	Read PORT of all pins (input and output pins) More...

void	setInterruptPolarityINTA (bool activeHigh)
	Set interrupt polarity INTA. More...

uint16_t	getPortInterruptMask ()
	Get interrupt mask all pins. More...

void	setPortInterruptEnable (uint16_t pins)
	Enable interrupt change on pins. More...

void	setPortInterruptDisable (uint16_t pins)
	Disable interrupt on pins. More...

bool	interruptINTA ()
	MCP23017 INTA pin changed. More...

uint16_t	registerRead (uint8_t reg)
	MCP23017 I2C read register. More...

void	registerWrite (uint8_t reg, uint16_t value)
	MCP23017 I2C write register. More...

uint8_t	getI2CStatus ()
	Return status of the last I2C write, returned by Wire endTransfer() More...

void	dumpRegisters (HardwareSerial *serial)
	Print I2C registers on serial port. More...

Public Attributes
uint16_t	portState
	Port state since last portRead() call.

uint16_t	pinsChanged
	Pins change on interrupt enabled pins since last intPinChanged() call.

uint16_t	pinsFalling
	Falling edge on interrupt enabled pins since last intPinChanged() call.

uint16_t	pinsRising
	Rising edge on interrupt eanbled pins since last intPinChanged() call.

Detailed Description

Erriez MCP23017 I2C IO-Expander class.

Definition at line 135 of file ErriezMCP23017.h.

Constructor & Destructor Documentation

◆ ErriezMCP23017()

ErriezMCP23017::ErriezMCP23017	(	uint8_t	i2cAddress = `MCP23017_I2C_ADDRESS`,
		TwoWire *	twoWire = `&Wire`
	)

ErriezMCP23017 Constructor.

The constructor initializes internal variables and does not call I2C functions

Parameters

i2cAddress	7-bit MCP23017 I2C device address
twoWire	Default is Wire object to select I2C bus.

Definition at line 38 of file ErriezMCP23017.cpp.

Member Function Documentation

◆ begin()

bool ErriezMCP23017::begin ( bool reset = true )

Initialize MCP23017.

Parameters

reset Perform resetting registers to default values (Default enabled)

Return values

true	MCP23017 detected
false	MCP23017 not detected

Definition at line 55 of file ErriezMCP23017.cpp.

◆ digitalRead()

int ErriezMCP23017::digitalRead ( uint8_t pin )

Get state of a single pin.

Parameters

pin	Pin number 0..15 (PORTA = 0..7, PORTB = 8..15)

Return values

HIGH	= 1
LOW	= 0

Definition at line 145 of file ErriezMCP23017.cpp.

◆ digitalWrite()

void ErriezMCP23017::digitalWrite	(	uint8_t	pin,
		uint8_t	state
	)

Set state of a single pin.

Parameters

pin	Pin number 0..15 (PORTA = 0..7, PORTB = 8..15)
state	HIGH = 1 LOW = 0

Definition at line 132 of file ErriezMCP23017.cpp.

◆ dumpRegisters()

void ErriezMCP23017::dumpRegisters ( HardwareSerial * serial )

Print I2C registers on serial port.

This function is optimized away by the compiler when not used

Parameters

serial Serial port

Definition at line 494 of file ErriezMCP23017.cpp.

◆ getI2CStatus()

uint8_t ErriezMCP23017::getI2CStatus ( )

Return status of the last I2C write, returned by Wire endTransfer()

Return values

0	Success
1	Data too long to fit in transmit buffer
2	Received NACK on transmit of address
3	Received NACK on transmit of data
4	Other error

Definition at line 480 of file ErriezMCP23017.cpp.

◆ getPortDirection()

uint16_t ErriezMCP23017::getPortDirection ( )

Get PORT direction all pins.

Returns: PORT direction pins 0..15, Arduino compatible:
Bit value '0': INPUT
Bit value '1': OUTPUT

Definition at line 174 of file ErriezMCP23017.cpp.

◆ getPortInterruptMask()

uint16_t ErriezMCP23017::getPortInterruptMask ( )

Get interrupt mask all pins.

Returns: Interrupt enabled

Definition at line 345 of file ErriezMCP23017.cpp.

◆ getPortPullup()

uint16_t ErriezMCP23017::getPortPullup ( )

Get PORT pullup all pins.

Returns: PORT pull-up pins 0..15:
Bit value '0': Pull-up disabled
Bit value '1': Pull-up enable

Definition at line 203 of file ErriezMCP23017.cpp.

◆ interruptINTA()

bool ErriezMCP23017::interruptINTA ( )

MCP23017 INTA pin changed.

The application should call this function when the MCP23017 INTA pin changed. Default: Falling edge This function re

Return values

true	At least one pin changed
false	No pins changed (Pin pulse was too short, or INTA edge did not match)

Returns: portState: PORT state since last portRead() call
pinsChanged: Changed pins on interrupt pins since last call
pinsFalling: Falling edge on interrupt pins since last call
pinsRising: Rising edge on interrupt pins since last call

Definition at line 401 of file ErriezMCP23017.cpp.

◆ pinMode()

void ErriezMCP23017::pinMode	(	uint8_t	pin,
		uint8_t	mode
	)

Set direction of a single pin.

Parameters

pin	Pin number 0..15 (PORTA = 0..7, PORTB = 8..15)
mode	OUTPUT: Configure pin as output INPUT: Configure pin as input INPUT_PULLUP: Configure pin with input pull-up

Definition at line 95 of file ErriezMCP23017.cpp.

◆ pinRead()

bool ErriezMCP23017::pinRead ( uint8_t pin )

Read state of a single pin (input and output pins)

Parameters

pin	Pin number 0..15 (PORTA = 0..7, PORTB = 8..15)

Return values

HIGH	= 1
LOW	= 0

Definition at line 248 of file ErriezMCP23017.cpp.

◆ pinToggle()

void ErriezMCP23017::pinToggle ( uint8_t pin )

Toggle state of a single pin (only for output pins)

Parameters

pin	Pin number 0..15 (PORTA = 0..7, PORTB = 8..15)

Definition at line 233 of file ErriezMCP23017.cpp.

◆ pinWrite()

void ErriezMCP23017::pinWrite	(	uint8_t	pin,
		bool	level
	)

Set pin state.

Parameters

pin	Pin number 0..15 (PORTA = 0..7, PORTB = 8..15)
level	HIGH = 1, LOW = 0

Definition at line 217 of file ErriezMCP23017.cpp.

◆ portMask()

void ErriezMCP23017::portMask	(	uint16_t	maskSet,
		uint16_t	maskClear
	)

Clear and set pin states.

Parameters

maskSet	Bit value '1': Pins to HIGH
maskClear	Bit value '1': Pins to LOW

Definition at line 293 of file ErriezMCP23017.cpp.

◆ portRead()

uint16_t ErriezMCP23017::portRead ( )

Read PORT of all pins (input and output pins)

Returns: State of all 16 pins

Definition at line 305 of file ErriezMCP23017.cpp.

◆ portToggle()

void ErriezMCP23017::portToggle ( uint16_t value )

Toggle pin states (output pins only)

Parameters

value 16 pins, bit value '0' = unchanged, '1' = toggle

Definition at line 278 of file ErriezMCP23017.cpp.

◆ portWrite()

void ErriezMCP23017::portWrite ( uint16_t value )

Set all pin states.

Parameters

value 16 pins, bit value '0' = LOW, '1' = HIGH

Definition at line 265 of file ErriezMCP23017.cpp.

◆ registerRead()

uint16_t ErriezMCP23017::registerRead ( uint8_t reg )

MCP23017 I2C read register.

Parameters

reg	MCP23017 register

Returns: MCP23017 register value

Definition at line 441 of file ErriezMCP23017.cpp.

◆ registerWrite()

void ErriezMCP23017::registerWrite	(	uint8_t	reg,
		uint16_t	value
	)

MCP23017 I2C write register.

Parameters

reg	MCP23017 register
value	MCP23017 value

Definition at line 461 of file ErriezMCP23017.cpp.

◆ setInterruptPolarityINTA()

void ErriezMCP23017::setInterruptPolarityINTA ( bool activeHigh )

Set interrupt polarity INTA.

Parameters

activeHigh HIGH = 1: Active high, LOW = 0: Active low (default)

Definition at line 320 of file ErriezMCP23017.cpp.

◆ setPortDirection()

void ErriezMCP23017::setPortDirection ( uint16_t outputPins )

Set PORT direction all pins.

Parameters

outputPins PORT direction pins 0..15, Arduino compatible:
Bit value '0': INPUT
Bit value '1': OUTPUT

Definition at line 159 of file ErriezMCP23017.cpp.

◆ setPortInterruptDisable()

void ErriezMCP23017::setPortInterruptDisable ( uint16_t pins )

Disable interrupt on pins.

Parameters

pins	Pins to disable

Definition at line 375 of file ErriezMCP23017.cpp.

◆ setPortInterruptEnable()

void ErriezMCP23017::setPortInterruptEnable ( uint16_t pins )

Enable interrupt change on pins.

The MCP23017 does not support edge interrupts. This is handled by software.

Parameters

pins	Pins to enable interrupt change

Definition at line 357 of file ErriezMCP23017.cpp.

◆ setPortPullup()

void ErriezMCP23017::setPortPullup ( uint16_t pullupPins )

Set PORT pullup all pins.

Parameters

pullupPins Set PORT pull-up pins 0..15:
Bit value '0': Pull-up unchanged
Bit value '1': Pull-up enable

Definition at line 188 of file ErriezMCP23017.cpp.

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

src/ErriezMCP23017.h
src/ErriezMCP23017.cpp

Public Member Functions

Public Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ErriezMCP23017()

Member Function Documentation

◆ begin()

◆ digitalRead()

◆ digitalWrite()

◆ dumpRegisters()

◆ getI2CStatus()

◆ getPortDirection()

◆ getPortInterruptMask()

◆ getPortPullup()

◆ interruptINTA()

◆ pinMode()

◆ pinRead()

◆ pinToggle()

◆ pinWrite()

◆ portMask()

◆ portRead()

◆ portToggle()

◆ portWrite()

◆ registerRead()

◆ registerWrite()

◆ setInterruptPolarityINTA()

◆ setPortDirection()

◆ setPortInterruptDisable()

◆ setPortInterruptEnable()

◆ setPortPullup()