Main API

Main data structures and functions. More...

Modules
	Interrupt Output
	Interrupt output functions.

Data Structures
struct	mcp23016_device
	Handle to a MCP23016 device. More...

Enumerations
enum	mcp23016_control { MCP23016_CONTROL_IARES_NORMAL = 0, MCP23016_CONTROL_IARES_FAST = 1 }
	Enum that describes I/O control values. More...

Functions
struct mcp23016_device *	mcp23016_open (const char *path, unsigned int num)
	Open the MCP23016 device specified by path and num. More...
void	mcp23016_close (struct mcp23016_device *dev)
	Close a MCP23016 device handle and free associated memory. More...
int	mcp23016_reset (struct mcp23016_device *dev)
	Issue a software reset, which resets registers to POR defaults and clears pending interrupts. More...
int	mcp23016_get_port (struct mcp23016_device *dev, uint16_t *val)
	Get the port value. More...
int	mcp23016_set_port (struct mcp23016_device *dev, uint16_t val)
	Set the port value. More...
int	mcp23016_get_output (struct mcp23016_device *dev, uint16_t *val)
	Get the output latch value. More...
int	mcp23016_set_output (struct mcp23016_device *dev, uint16_t val)
	Set the output latch value. More...
int	mcp23016_get_polarity (struct mcp23016_device *dev, uint16_t *val)
	Get the input polarity value. More...
int	mcp23016_set_polarity (struct mcp23016_device *dev, uint16_t val)
	Set the input polarity value. More...
int	mcp23016_get_direction (struct mcp23016_device *dev, uint16_t *val)
	Get the I/O direction value. More...
int	mcp23016_set_direction (struct mcp23016_device *dev, uint16_t val)
	Set the I/O direction value. More...
int	mcp23016_get_interrupt (struct mcp23016_device *dev, uint16_t *val)
	Get the interrupt capture value. More...
static int	mcp23016_clear_interrupt (struct mcp23016_device *dev)
	Clear interrupt status. More...
int	mcp23016_get_control (struct mcp23016_device *dev, uint16_t *val)
	Get the I/O control value. More...
int	mcp23016_set_control (struct mcp23016_device *dev, uint16_t val)
	Set the I/O control value. More...

Detailed Description

Main data structures and functions.

#include <mcp23016.h>

Enumeration Type Documentation

mcp23016_control

enum mcp23016_control

Enum that describes I/O control values.

Enumerator
MCP23016_CONTROL_IARES_NORMAL	Normal interrupt activity resolution (32ms).
MCP23016_CONTROL_IARES_FAST	Fast interrupt activity resolution (200us).

Function Documentation

mcp23016_clear_interrupt()

static int mcp23016_clear_interrupt ( struct mcp23016_device *  dev )

inlinestatic

Clear interrupt status.

Parameters

dev	Pointer to a MCP23016 device handle.

Returns

0 on success, or -1 on error with errno set appropriately.

This function is equivalent to calling:

uint16_t dummy;
mcp23016_get_interrupt(dev, &dummy);

mcp23016_close()

void mcp23016_close

(

struct mcp23016_device *

dev

)

Close a MCP23016 device handle and free associated memory.

Parameters

dev	Pointer to a MCP23016 device handle.

Once closed, dev is no longer valid for use.

mcp23016_get_control()

int mcp23016_get_control	(	struct mcp23016_device *	dev,
		uint16_t *	val
	)

Get the I/O control value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	Pointer to the value to receive.

Returns

0 on success, or -1 on error with errno set appropriately.

This function returns the value of the IOCON0 and IOCON1 registers in the low and high bytes, respectively.

mcp23016_get_direction()

int mcp23016_get_direction	(	struct mcp23016_device *	dev,
		uint16_t *	val
	)

Get the I/O direction value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	Pointer to the value to receive.

Returns

0 on success, or -1 on error with errno set appropriately.

This function returns the value of the IODIR0 and IODIR1 registers in the low and high bytes, respectively.

mcp23016_get_interrupt()

int mcp23016_get_interrupt	(	struct mcp23016_device *	dev,
		uint16_t *	val
	)

Get the interrupt capture value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	Pointer to the value to receive.

Returns

0 on success, or -1 on error with errno set appropriately.

This function returns the value of the INTCAP0 and INTCAP1 registers in the low and high bytes, respectively.

mcp23016_get_output()

int mcp23016_get_output	(	struct mcp23016_device *	dev,
		uint16_t *	val
	)

Get the output latch value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	Pointer to the value to receive.

Returns

0 on success, or -1 on error with errno set appropriately.

This function returns the value of the OLAT0 and OLAT1 registers in the low and high bytes, respectively.

mcp23016_get_polarity()

int mcp23016_get_polarity	(	struct mcp23016_device *	dev,
		uint16_t *	val
	)

Get the input polarity value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	Pointer to the value to receive.

Returns

0 on success, or -1 on error with errno set appropriately.

This function returns the value of the IPOL0 and IPOL1 registers in the low and high bytes, respectively.

mcp23016_get_port()

int mcp23016_get_port	(	struct mcp23016_device *	dev,
		uint16_t *	val
	)

Get the port value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	Pointer to the value to receive.

Returns

0 on success, or -1 on error with errno set appropriately.

This function returns the value of the GP0 and GP1 registers in the low and high bytes, respectively.

mcp23016_open()

struct mcp23016_device* mcp23016_open	(	const char *	path,
		unsigned int	num
	)

Open the MCP23016 device specified by path and num.

Parameters

path	Pointer to an I2C character device.
num	Relative position of device on I2C bus (ie. AD0-2).

Returns

Pointer to a MCP23016 device handle, or NULL on error with errno set appropriately.

mcp23016_reset()

int mcp23016_reset

(

struct mcp23016_device *

dev

)

Issue a software reset, which resets registers to POR defaults and clears pending interrupts.

Parameters

dev	Pointer to a MCP23016 device handle.

Returns

0 on success, or -1 on error with errno set appropriately.

mcp23016_set_control()

int mcp23016_set_control	(	struct mcp23016_device *	dev,
		uint16_t	val
	)

Set the I/O control value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	The value to set.

Returns

0 on success, or -1 on error with errno set appropriately.

This function writes the value of the IOCON0 and IOCON1 registers in the low and high bytes, respectively.

mcp23016_set_direction()

int mcp23016_set_direction	(	struct mcp23016_device *	dev,
		uint16_t	val
	)

Set the I/O direction value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	The value to set.

Returns

0 on success, or -1 on error with errno set appropriately.

This function writes the value of the IODIR0 and IODIR1 registers in the low and high bytes, respectively.

mcp23016_set_output()

int mcp23016_set_output	(	struct mcp23016_device *	dev,
		uint16_t	val
	)

Set the output latch value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	The value to set.

Returns

0 on success, or -1 on error with errno set appropriately.

This function writes the value of the OLAT0 and OLAT1 registers in the low and high bytes, respectively.

mcp23016_set_polarity()

int mcp23016_set_polarity	(	struct mcp23016_device *	dev,
		uint16_t	val
	)

Set the input polarity value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	The value to set.

Returns

0 on success, or -1 on error with errno set appropriately.

This function writes the value of the IPOL0 and IPOL1 registers in the low and high bytes, respectively.

mcp23016_set_port()

int mcp23016_set_port	(	struct mcp23016_device *	dev,
		uint16_t	val
	)

Set the port value.

Parameters

dev	Pointer to a MCP23016 device handle.
val	The value to set.

Returns

0 on success, or -1 on error with errno set appropriately.

This function writes the value of the GP0 and GP1 registers in the low and high bytes, respectively.