Examples

Complete ESP32-S3 applications that exercise the driver on a PCA9555 or PCAL9555A, one test suite and one demo.

They run on an ESP32-S3 board wired as on the Hardware page; the pins are in esp32_pcal95555_test_config.hpp and the port in esp32_pcal95555_bus.hpp. CI builds every app below on each pull request.

The apps

App	What it shows	Source	CI
pcal95555_comprehensive_test	Comprehensive PCAL95555 GPIO expander test suite covering all functionality	pcal95555_comprehensive_test.cpp	yes
pcal95555_led_animation	LED animation demo driving 16 LEDs through PCA9555/PCAL9555A with visual patterns	pcal95555_led_animation.cpp	yes

Build and flash one (from examples/esp32, ESP-IDF environment loaded):

./scripts/build_app.sh pcal95555_comprehensive_test Release
./scripts/flash_app.sh flash_monitor pcal95555_comprehensive_test Release

Source of this table: examples/esp32/app_config.yml.

Set up once

git submodule update --init examples/esp32/scripts   # the HardFOC ESP-IDF build scripts
cd examples/esp32
. $IDF_PATH/export.sh                                 # ESP-IDF v5.5
./scripts/build_app.sh list                           # every app and build type

The scripts read app_config.yml (the same file this page's table comes from) and build each app as its own firmware image.

What to read in an example

You want to	Read
See every driver call checked against the hardware, with PCAL9555A-only sections skipped on a PCA9555	pcal95555_comprehensive_test.cpp, one function per test section
Drive 16 LEDs with only the standard registers (works on both parts)	pcal95555_led_animation.cpp
Wire up interrupts with a GPIO ISR and a FreeRTOS task	esp32_pcal95555_bus.hpp, RegisterInterruptHandler()
Change the address at run time through GPIO-driven A0-A2	esp32_pcal95555_bus.hpp, SetAddressPins(); the test's address section

The example folder's README has the wiring, the expected serial output and the per-section notes of the comprehensive test.