Crate aw9523_embedded 

AW9523 GPIO Expander Driver

A platform-agnostic driver for the AW9523 16-channel LED driver and GPIO expander.

The AW9523 is an I2C-controlled GPIO expander with 16 configurable pins that can operate as digital I/O or constant-current LED drivers. Each pin supports:

• Digital input/output with configurable direction
• Interrupt detection
• 256-step constant current LED driving
• Open-drain or push-pull output modes (port 0)

Features

• no_std compatible
• Uses embedded-hal traits for portability
• Individual pin control or bulk 16-bit operations
• Configurable interrupt detection per pin
• LED mode with PWM-like current control
• Async support via the async feature (requires embedded-hal-async)

Blocking Example

use aw9523::{Aw9523, PinMode, HIGH};

// Create device with I2C bus and default address
let mut gpio = Aw9523::new(i2c, 0x58);

// Initialize with default configuration
gpio.init().unwrap();

// Configure pin 0 as output and set it high
gpio.pin_mode(0, PinMode::Output).unwrap();
gpio.digital_write(0, HIGH).unwrap();

// Configure pin 8 as input and read it
gpio.pin_mode(8, PinMode::Input).unwrap();
let state = gpio.digital_read(8).unwrap();

Async Example

Enable the async feature in your Cargo.toml:

[dependencies]
aw9523-embedded = { version = "0.1", features = ["async"] }

Then use the async API:

use aw9523::{r#async::Aw9523Async, PinMode, HIGH};

async fn example() {
    // Create device with async I2C bus
    let mut gpio = Aw9523Async::new(i2c, 0x58);

    // All methods are async
    gpio.init().await.unwrap();
    gpio.pin_mode(0, PinMode::Output).await.unwrap();
    gpio.digital_write(0, HIGH).await.unwrap();
}

Structs

Aw9523

AW9523 driver instance

Enums

Aw9523Error

Errors that can occur when interacting with the AW9523

PinMode

Pin mode/direction configuration.

PinState

Digital output pin state.

Constants

AW9523_ALL_PINS

Bitmask for all 16 pins

AW9523_LED_MODE

Pin mode constant for LED/constant-current mode. Use with Aw9523::pin_mode to configure a pin for LED driving.

AW9523_P0_0

Port 0, pin 0 alias for PIN_0. The AW9523 organizes its 16 pins into two ports of 8 pins each, and this is the first pin in port 0.

AW9523_P0_1

Port 0, pin 1 alias for PIN_1. This is the second pin in port 0, useful when you need port-based naming conventions.

AW9523_P0_2

Port 0, pin 2 alias for PIN_2. This is the third pin in port 0, sharing the same register space as other port 0 pins.

AW9523_P0_3

Port 0, pin 3 alias for PIN_3. This is the fourth pin in port 0, part of the lower byte of the 16-bit pin registers.

AW9523_P0_4

Port 0, pin 4 alias for PIN_4. The middle pin of port 0, this can be configured for open-drain mode along with other port 0 pins.

AW9523_P0_5

Port 0, pin 5 alias for PIN_5. This pin is part of port 0, which supports open-drain output configuration via the GCR register.

AW9523_P0_6

Port 0, pin 6 alias for PIN_6. One of the higher-numbered pins in port 0, accessible through the lower-byte registers.

AW9523_P0_7

Port 0, pin 7 alias for PIN_7. The last pin in port 0, representing bit 7 of the port 0 register space.

AW9523_P1_0

Port 1, pin 0 alias for PIN_8. The first pin in port 1, which always operates in push-pull mode (unlike port 0).

AW9523_P1_1

Port 1, pin 1 alias for PIN_9. This is the second pin in port 1, accessed through the upper-byte registers.

AW9523_P1_2

Port 1, pin 2 alias for PIN_10. The third pin in port 1, part of the upper byte of the 16-bit pin registers.

AW9523_P1_3

Port 1, pin 3 alias for PIN_11. This is the fourth pin in port 1, useful when organizing pins by port groups.

AW9523_P1_4

Port 1, pin 4 alias for PIN_12. The middle pin of port 1, can be used with LED dimming functionality.

AW9523_P1_5

Port 1, pin 5 alias for PIN_13. This pin is part of port 1’s push-pull output group, accessible via upper-byte registers.

AW9523_P1_6

Port 1, pin 6 alias for PIN_14. One of the higher-numbered pins in port 1, supporting all standard GPIO and LED modes.

AW9523_P1_7

Port 1, pin 7 alias for PIN_15. The last pin on the AW9523, representing the highest bit in the 16-bit register space.

AW9523_PIN_0

Bitmask for pin 0

AW9523_PIN_1

Bitmask for pin 1

AW9523_PIN_2

Bitmask for pin 2

AW9523_PIN_3

Bitmask for pin 3

AW9523_PIN_4

Bitmask for pin 4

AW9523_PIN_5

Bitmask for pin 5

AW9523_PIN_6

Bitmask for pin 6

AW9523_PIN_7

Bitmask for pin 7

AW9523_PIN_8

Bitmask for pin 8

AW9523_PIN_9

Bitmask for pin 9

AW9523_PIN_10

Bitmask for pin 10

AW9523_PIN_11

Bitmask for pin 11

AW9523_PIN_12

Bitmask for pin 12

AW9523_PIN_13

Bitmask for pin 13

AW9523_PIN_14

Bitmask for pin 14

AW9523_PIN_15

Bitmask for pin 15

AW9523_PORT0_ALL

Bitmask for all pins in port 0 (pins 0-7)

AW9523_PORT1_ALL

Bitmask for all pins in port 1 (pins 8-15)

AW9523_REG_CHIPID

Chip ID register (read-only, returns 0x23)

AW9523_REG_INPUT1

Input port 1 register (pins 8-15)

AW9523_REG_INTENABLE1

Interrupt enable port 1 register

HIGH

Constant for HIGH pin state

INPUT

Pin mode constant for input direction (deprecated, use PinMode::Input instead)

LOW

Constant for LOW pin state

OUTPUT

Pin mode constant for output direction (deprecated, use PinMode::Output instead)