PCA9535 Example

This example shows how to use the espp::Pca9535 driver to talk to a PCA9535 / PCA9555 16-bit I2C GPIO expander:

• configure pin directions per port

• read the input pins

• drive the output pins

How to use example

Hardware Required

This example requires a connection (via I2C) to a board with a PCA9535 (or the register-identical PCA9555) I/O expander. Configure the I2C pins (SDA/SCL) via menuconfig for your board.

Build and Flash

Build the project and flash it to the board, then run the monitor tool to view serial output:

idf.py -p PORT flash monitor

(Replace PORT with the name of the serial port to use.)

(To exit the serial monitor, type Ctrl-].)

Example Output

The example configures the expander’s ports, then logs the input pin state and toggles an output in a loop.