AW9523 GPIO expander component. More...

#include <stdbool.h>
#include <stdint.h>
#include "driver/i2c_types.h"
#include "esp_err.h"

Macros
#define	AW9523_ID 0x23
	ID returned by the AW9523 GPIO expander when reading from the AW9523_REG_ID register.

Typedefs
typedef bool	aw9523_pin_data_digital_t
	GPIO digital pin data to read/write.
typedef uint8_t	aw9523_pin_num_t
	Pin number, ranging from 0 to 15 inclusive.
typedef aw9523_pin_data_digital_t	aw9523_pins_data_digital_t[16]
	GPIO digital pin data to read/write for all 16 pins.
typedef aw9523_pin_interrupt_mode_t	aw9523_pins_interrupt_mode_t[16]
	Interrupt mode for all 16 GPIO input pins.
typedef aw9523_pin_mode_t	aw9523_pins_mode_t[16]
	Pin mode of all 16 pins.
typedef uint8_t	aw9523_reg_value_t
	Register value read from and/or to write to the AW9523 GPIO expander.
typedef i2c_master_dev_handle_t	aw9523_t
	AW9523 GPIO expander's I2C device handle.

Enumerations
enum	aw9523_gpio_output_mode_t { AW9523_GPIO_OUTPUT_MODE_OPEN_DRAIN = 0b0 , AW9523_GPIO_OUTPUT_MODE_PUSH_PULL = 0b1 }
	GPIO output mode for all port 0 pins (pins 0 to 7). More...
enum	aw9523_i2c_addr_t { AW9523_I2C_ADDR_AD0_GND_AD1_GND = 0x58 , AW9523_I2C_ADDR_AD0_VCC_AD1_GND = 0x59 , AW9523_I2C_ADDR_AD0_GND_AD1_VCC = 0x5A , AW9523_I2C_ADDR_AD0_VCC_AD1_VCC = 0x5B }
	I2C address of the AW9523 GPIO expander. More...
enum	aw9523_led_max_current_t { AW9523_LED_MAX_mA_37 = 0x0 , AW9523_LED_MAX_mA_27_75 = 0x1 , AW9523_LED_MAX_mA_18_5 = 0x2 , AW9523_LED_MAX_mA_9_25 = 0x3 }
	Maximum current for all LED output pins. More...
enum	aw9523_pin_interrupt_mode_t { AW9523_PIN_INTERRUPT_MODE_ENABLE = 0b0 , AW9523_PIN_INTERRUPT_MODE_DISABLE = 0b1 }
	Interrupt mode on/off for a GPIO input pin. More...
enum	aw9523_pin_mode_t { AW9523_PIN_GPIO_OUTPUT = 0 , AW9523_PIN_GPIO_INPUT = 1 , AW9523_PIN_LED = 2 }
	Pin mode of a specific pin. More...
enum	aw9523_reg_addr_t { AW9523_REG_GPIO_INPUT_P0 = 0x00 , AW9523_REG_GPIO_INPUT_P1 = 0x01 , AW9523_REG_GPIO_OUTPUT_P0 = 0x02 , AW9523_REG_GPIO_OUTPUT_P1 = 0x03 , AW9523_REG_GPIO_DIR_P0 = 0x04 , AW9523_REG_GPIO_DIR_P1 = 0x05 , AW9523_REG_GPIO_INTERRUPT_P0 = 0x06 , AW9523_REG_GPIO_INTERRUPT_P1 = 0x07 , AW9523_REG_ID = 0x10 , AW9523_REG_CONTROL = 0x11 , AW9523_REG_MODE_P0 = 0x12 , AW9523_REG_MODE_P1 = 0x13 , AW9523_REG_SOFT_RESET = 0x7F }
	Register address constants to read from and/or write to for the AW9523 GPIO expander. More...

Functions
esp_err_t	aw9523_destroy (aw9523_t *dev)
	Soft reset and remove the I2C instance of the AW9523 GPIO expander.
esp_err_t	aw9523_gpio_read_pin (const aw9523_t dev, const aw9523_pin_num_t pin, const aw9523_pin_mode_t pin_mode, aw9523_pin_data_digital_t data)
	Read digital pin data from a specific GPIO pin.
esp_err_t	aw9523_gpio_read_pins (const aw9523_t dev, aw9523_pins_data_digital_t pins_data)
	Read all GPIO pins.
esp_err_t	aw9523_gpio_write_pin (const aw9523_t *dev, const aw9523_pin_num_t pin, const aw9523_pin_data_digital_t data)
	Write digital pin data to specific GPIO output pin.
esp_err_t	aw9523_gpio_write_pins (const aw9523_t dev, const aw9523_pins_data_digital_t data)
	Write digital pin data to all GPIO output pins.
esp_err_t	aw9523_init (const i2c_master_bus_handle_t bus_handle, const aw9523_i2c_addr_t address, aw9523_t dev)
	Initialise the AW9523 GPIO expander.
esp_err_t	aw9523_read_reg (const aw9523_t dev, const aw9523_reg_addr_t reg, aw9523_reg_value_t value)
	Read the specified register from the AW9523 GPIO expander.
esp_err_t	aw9523_set_gpio_interrupt_pin (const aw9523_t *dev, const aw9523_pin_num_t pin, const aw9523_pin_interrupt_mode_t pin_interrupt_mode)
	Set interrupt pin mode for specific GPIO input pin.
esp_err_t	aw9523_set_gpio_interrupt_pins (const aw9523_t dev, const aw9523_pins_interrupt_mode_t pins_interrupt_mode)
	Set interrupt pin mode for all GPIO input pins.
esp_err_t	aw9523_set_gpio_output_mode_p0 (const aw9523_t *dev, const aw9523_gpio_output_mode_t gpio_output_mode)
	Set GPIO output mode of all pins in port 0 (pins 0 to 7).
esp_err_t	aw9523_set_led_brightness (const aw9523_t *dev, const aw9523_pin_num_t pin, const aw9523_reg_value_t brightness)
	Set LED brightness of specific LED pin in LED mode.
esp_err_t	aw9523_set_led_max_current (const aw9523_t *dev, const aw9523_led_max_current_t max_current)
	Set max current output of LED pins in LED mode.
esp_err_t	aw9523_set_pin (const aw9523_t *dev, const aw9523_pin_num_t pin, const aw9523_pin_mode_t pin_mode)
	Set pin mode of a specific pin.
esp_err_t	aw9523_set_pins (const aw9523_t dev, const aw9523_pins_mode_t pins_mode)
	Set pin mode of all 16 pins.
esp_err_t	aw9523_soft_reset (const aw9523_t *dev)
	Soft reset the AW9523 GPIO expander.
esp_err_t	aw9523_write_reg (const aw9523_t *dev, const aw9523_reg_addr_t reg, const aw9523_reg_value_t value)
	Write the specified register to the AW9523 GPIO expander.

Detailed Description

AW9523 GPIO expander component.

Author: Yik Jin (@yikjin) yikji.nosp@m.n@nu.nosp@m.shack.nosp@m.ers..nosp@m.org

Version: 0.0.3

Date: 2026-01-05

Copyright: Copyright (c) 2026 NUS Hackers

This component simplifies communication with the AW9523 GPIO expander module, and abstracts away having to deal with the 2 physical ports (P0 and P1) of 8 pins (Pn_0..7) each in the device, representing them as 16 virtual pins instead (0..15) for ease of use.

Enumeration Type Documentation

◆ aw9523_gpio_output_mode_t

enum aw9523_gpio_output_mode_t

GPIO output mode for all port 0 pins (pins 0 to 7).

Enumerator
AW9523_GPIO_OUTPUT_MODE_OPEN_DRAIN	0b0	Open drain GPIO output mode
AW9523_GPIO_OUTPUT_MODE_PUSH_PULL	0b1	Push pull GPIO output mode

◆ aw9523_i2c_addr_t

enum aw9523_i2c_addr_t

I2C address of the AW9523 GPIO expander.

Enumerator
AW9523_I2C_ADDR_AD0_GND_AD1_GND	0x58	AD0 and AD1 connected to GND
AW9523_I2C_ADDR_AD0_VCC_AD1_GND	0x59	AD0 connected to VCC, and AD1 connected to GND
AW9523_I2C_ADDR_AD0_GND_AD1_VCC	0x5A	AD0 connected to GND, and AD1 connected to VCC
AW9523_I2C_ADDR_AD0_VCC_AD1_VCC	0x5B	AD0 and AD1 connected to VCC

◆ aw9523_led_max_current_t

enum aw9523_led_max_current_t

Maximum current for all LED output pins.

Enumerator
AW9523_LED_MAX_mA_37	0x0	37 mA max current for all LED output pins
AW9523_LED_MAX_mA_27_75	0x1	27.75 mA max current for all LED output pins
AW9523_LED_MAX_mA_18_5	0x2	18.5 mA max current for all LED output pins
AW9523_LED_MAX_mA_9_25	0x3	9.25 mA max current for all LED output pins

◆ aw9523_pin_interrupt_mode_t

enum aw9523_pin_interrupt_mode_t

Interrupt mode on/off for a GPIO input pin.

Enumerator
AW9523_PIN_INTERRUPT_MODE_ENABLE	0b0	Enable interrupt for GPIO input pin
AW9523_PIN_INTERRUPT_MODE_DISABLE	0b1	Disable interrupt for GPIO input pin

◆ aw9523_pin_mode_t

enum aw9523_pin_mode_t

Pin mode of a specific pin.

Enumerator
AW9523_PIN_GPIO_OUTPUT	0	GPIO output pin mode
AW9523_PIN_GPIO_INPUT	1	GPIO input pin mode
AW9523_PIN_LED	2	LED pin mode

◆ aw9523_reg_addr_t

enum aw9523_reg_addr_t

Register address constants to read from and/or write to for the AW9523 GPIO expander.

Enumerator
AW9523_REG_GPIO_INPUT_P0	0x00	GPIO pins' input values for port 0 (pins 0 to 7) (read-only)
AW9523_REG_GPIO_INPUT_P1	0x01	GPIO pins' input values for port 1 (pins 8 to 15) (read-only)
AW9523_REG_GPIO_OUTPUT_P0	0x02	GPIO pins' output values for port 0 (pins 0 to 7) (read/write)
AW9523_REG_GPIO_OUTPUT_P1	0x03	GPIO pins' output values for port 1 (pins 8 to 15) (read/write)
AW9523_REG_GPIO_DIR_P0	0x04	GPIO pins' direction (input/output) for port 0 (pins 0 to 7) (read/write)
AW9523_REG_GPIO_DIR_P1	0x05	GPIO pins' direction (input/output) for port 1 (pins 8 to 15) (read/write)
AW9523_REG_GPIO_INTERRUPT_P0	0x06	GPIO input pins' interrupt status for port 0 (pins 0 to 7) (read/write)
AW9523_REG_GPIO_INTERRUPT_P1	0x07	GPIO input pins' interrupt status for port 1 (pins 8 to 15) (read/write)
AW9523_REG_ID	0x10	Constant ID value (read-only)
AW9523_REG_CONTROL	0x11	Control register (read/write)
AW9523_REG_MODE_P0	0x12	GPIO or LED pins mode for port 0 (pins 0 to 7) (read/write)
AW9523_REG_MODE_P1	0x13	GPIO or LED pins mode for port 1 (pins 8 to 15) (read/write)
AW9523_REG_SOFT_RESET	0x7F	Soft reset to default state (write-only)

Function Documentation

◆ aw9523_destroy()

esp_err_t aw9523_destroy ( aw9523_t * dev )

Soft reset and remove the I2C instance of the AW9523 GPIO expander.

Parameters

[in,out] dev I2C device handle of the AW9523 GPIO expander

Returns: esp_err_t ESP error constants

◆ aw9523_gpio_read_pin()

esp_err_t aw9523_gpio_read_pin	(	const aw9523_t *	dev,
		const aw9523_pin_num_t	pin,
		const aw9523_pin_mode_t	pin_mode,
		aw9523_pin_data_digital_t *	data )

Read digital pin data from a specific GPIO pin.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	pin	Pin number to read from
[in]	pin_mode	If the specified pin is in GPIO input or output mode
[out]	data	GPIO digital pin data read from the pin number

Returns: esp_err_t ESP error constants

◆ aw9523_gpio_read_pins()

esp_err_t aw9523_gpio_read_pins	(	const aw9523_t *	dev,
		aw9523_pins_data_digital_t *	pins_data )

Read all GPIO pins.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[out]	pins_data	Pin mode read from all 16 pins

Returns: esp_err_t ESP error constants

◆ aw9523_gpio_write_pin()

esp_err_t aw9523_gpio_write_pin	(	const aw9523_t *	dev,
		const aw9523_pin_num_t	pin,
		const aw9523_pin_data_digital_t	data )

Write digital pin data to specific GPIO output pin.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	pin	GPIO output pin number to write to
[in]	data	Digital data to write to the specified GPIO output pin

Returns: esp_err_t ESP error constants

◆ aw9523_gpio_write_pins()

esp_err_t aw9523_gpio_write_pins	(	const aw9523_t *	dev,
		const aw9523_pins_data_digital_t *	data )

Write digital pin data to all GPIO output pins.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	data	Digital data to write to each GPIO output pin

Returns: esp_err_t ESP error constants

◆ aw9523_init()

esp_err_t aw9523_init	(	const i2c_master_bus_handle_t *	bus_handle,
		const aw9523_i2c_addr_t	address,
		aw9523_t *	dev )

Initialise the AW9523 GPIO expander.

Parameters

[in]	bus_handle	I2C master bus handle
[in]	address	I2C address of the AW9523 GPIO expander
[out]	dev	I2C device handle of the AW9523 GPIO expander

Returns: esp_err_t ESP error constants

◆ aw9523_read_reg()

esp_err_t aw9523_read_reg	(	const aw9523_t *	dev,
		const aw9523_reg_addr_t	reg,
		aw9523_reg_value_t *	value )

Read the specified register from the AW9523 GPIO expander.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	reg	Register address to read from
[out]	value	Value read from the specified register

Returns: esp_err_t ESP error constants

◆ aw9523_set_gpio_interrupt_pin()

esp_err_t aw9523_set_gpio_interrupt_pin	(	const aw9523_t *	dev,
		const aw9523_pin_num_t	pin,
		const aw9523_pin_interrupt_mode_t	pin_interrupt_mode )

Set interrupt pin mode for specific GPIO input pin.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	pin	GPIO input pin to set interrupt pin mode of
[in]	pin_interrupt_mode	Interrupt mode to set the specified pin to

Returns: esp_err_t ESP error constants

◆ aw9523_set_gpio_interrupt_pins()

esp_err_t aw9523_set_gpio_interrupt_pins	(	const aw9523_t *	dev,
		const aw9523_pins_interrupt_mode_t *	pins_interrupt_mode )

Set interrupt pin mode for all GPIO input pins.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	pins_interrupt_mode	Interrupt mode to set for each GPIO input pin

Returns: esp_err_t ESP error constants

◆ aw9523_set_gpio_output_mode_p0()

esp_err_t aw9523_set_gpio_output_mode_p0	(	const aw9523_t *	dev,
		const aw9523_gpio_output_mode_t	gpio_output_mode )

Set GPIO output mode of all pins in port 0 (pins 0 to 7).

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	gpio_output_mode	GPIO output mode to set all of pins 0 to 7 to

Returns: esp_err_t ESP error constants

◆ aw9523_set_led_brightness()

esp_err_t aw9523_set_led_brightness	(	const aw9523_t *	dev,
		const aw9523_pin_num_t	pin,
		const aw9523_reg_value_t	brightness )

Set LED brightness of specific LED pin in LED mode.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	pin	LED pin number to set LED brightness of
[in]	brightness	LED brightness value from 0 (0x00) to 255 (0xFF)

Returns: esp_err_t ESP error constants

◆ aw9523_set_led_max_current()

esp_err_t aw9523_set_led_max_current	(	const aw9523_t *	dev,
		const aw9523_led_max_current_t	max_current )

Set max current output of LED pins in LED mode.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	max_current	Max current output of LED pins

Returns: esp_err_t ESP error constants

◆ aw9523_set_pin()

esp_err_t aw9523_set_pin	(	const aw9523_t *	dev,
		const aw9523_pin_num_t	pin,
		const aw9523_pin_mode_t	pin_mode )

Set pin mode of a specific pin.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	pin	Pin number to update the pin mode of
[in]	pin_mode	New pin mode for the specified pin number

Returns: esp_err_t ESP error constants

◆ aw9523_set_pins()

esp_err_t aw9523_set_pins	(	const aw9523_t *	dev,
		const aw9523_pins_mode_t *	pins_mode )

Set pin mode of all 16 pins.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	pins_mode	Pin mode of all 16 pins

Returns: esp_err_t ESP error constants

◆ aw9523_soft_reset()

esp_err_t aw9523_soft_reset ( const aw9523_t * dev )

Soft reset the AW9523 GPIO expander.

Parameters

[in] dev I2C device handle of the AW9523 GPIO expander

Returns: esp_err_t ESP error constants

◆ aw9523_write_reg()

esp_err_t aw9523_write_reg	(	const aw9523_t *	dev,
		const aw9523_reg_addr_t	reg,
		const aw9523_reg_value_t	value )

Write the specified register to the AW9523 GPIO expander.

Parameters

[in]	dev	I2C device handle of the AW9523 GPIO expander
[in]	reg	Register address to write to
[in]	value	Value to write to the specified register

Returns: esp_err_t ESP error constants

Macros

Typedefs

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

◆ aw9523_gpio_output_mode_t

◆ aw9523_i2c_addr_t

◆ aw9523_led_max_current_t

◆ aw9523_pin_interrupt_mode_t

◆ aw9523_pin_mode_t

◆ aw9523_reg_addr_t

Function Documentation

◆ aw9523_destroy()

◆ aw9523_gpio_read_pin()

◆ aw9523_gpio_read_pins()

◆ aw9523_gpio_write_pin()

◆ aw9523_gpio_write_pins()

◆ aw9523_init()

◆ aw9523_read_reg()

◆ aw9523_set_gpio_interrupt_pin()

◆ aw9523_set_gpio_interrupt_pins()

◆ aw9523_set_gpio_output_mode_p0()

◆ aw9523_set_led_brightness()

◆ aw9523_set_led_max_current()

◆ aw9523_set_pin()

◆ aw9523_set_pins()

◆ aw9523_soft_reset()

◆ aw9523_write_reg()