ESPSomfy-RTS with Homekit

Note for this fork

This code has been created to merge the ESPSomfy-RTS controller with Homekit. This should allow the device to connect directly with homekit and expose shades there.

NOTE: THIS HAS BEEN CREATED WITH THE HELP OF AI.

For all technical details like how to build the appropriate device, please refer to ESPSomfy-RTS. This project has followed the same approach.

Hardware requirements

Flash size

The HomeKit branch requires a minimum of 8 MB flash. The HomeKit Accessory Protocol (HAP) stack adds pinned partitions near the top of flash, and two OTA app slots at 3 MB each leave no room to fit within a 4 MB device. Devices with 4 MB flash (e.g. standard ESP32, ESP32-C3) are not supported by this fork.

Tested hardware

CC1101 wiring (ESP32-S3)

CC1101 pin	ESP32-S3 GPIO
GDO0	GPIO 3
GDO2	GPIO 4
CSN	GPIO 6
SCK	GPIO 7
MISO	GPIO 8
MOSI	GPIO 9
VCC	3.3 V
GND	GND

Build environment

This project targets ESP-IDF v5.5 with arduino-esp32 v3.x embedded as a component (not the Arduino IDE).

idf.py build
idf.py -p /dev/cu.usbmodem<PORT> flash monitor

CC1101 driver notes (arduino-esp32 v3.x)

The upstream SmartRC-CC1101-Driver-Lib was written for arduino-esp32 v2.x. The copy in components/CC1101/ contains three fixes required for v3.x:

1. SPI.begin(..., -1) — pass -1 for the SS argument so the pin is not routed through the hardware CS peripheral, allowing Reset() to strobe it manually via digitalWrite.
2. SPI.beginTransaction(SPISettings(4000000, MSBFIRST, SPI_MODE0)) added to SpiStart() — on v3.x SPI.transfer() without a prior beginTransaction() does not configure the hardware clock and hangs indefinitely.
3. SpiEnd() is called immediately after Reset() in Init(), before RegConfigSettings() — this prevents a mutex deadlock caused by RegConfigSettings() → SpiWriteReg() → SpiStart() → beginTransaction() trying to re-lock the non-reentrant SPI mutex while the outer Init() still holds it.