chore: Downgrade ESP-IDF from v6.1.0 to v5.5.2

Matches the version deployed on ESP32 sensors. Removes v6.1
workaround, updates all docs to reflect v5.5.2, regenerates
sdkconfig for the correct IDF version.

PROJECT.md

@@ -25,7 +25,7 @@ Firmware customization and experimentation for ESP32 CSI (Channel State Informat
 ## Software Stack
 | Component | Version | Purpose |
 |-----------|---------|---------|
-| ESP-IDF | v5.x | Development framework |
+| ESP-IDF | v5.5.2 | Development framework (`~/esp/esp-idf/`) |
 | esp-csi | latest | CSI extraction library |
 | FreeRTOS | (bundled) | RTOS kernel |
 

ROADMAP.md

@@ -1,12 +1,12 @@
 # ESP32 Hacking Roadmap
 
-## v0.1 - Documentation & Setup [CURRENT]
+## v0.1 - Documentation & Setup [DONE]
 - [x] Copy firmware sources from esp-csi
 - [x] Document current firmware behavior
 - [x] Document CSI data format
 - [x] Document build & flash process
 - [x] List firmware modification ideas with priorities
-- [ ] Create development workflow (build, flash, test cycle)
+- [x] Verify build from repo (ESP-IDF v5.5.2, aarch64)
 
 ## v0.2 - Remote Management
 - [ ] Add UDP command listener on ESP32

TASKS.md

@@ -23,7 +23,7 @@
 
 ## Notes
 
-- Build confirmed working on ESP-IDF v6.1.0 (aarch64/Pi 5)
-- Workaround needed: symlink `6.0` → `6.1` in `esp_csi_gain_ctrl` managed component
+- Build confirmed working on ESP-IDF v5.5.2 (aarch64/Pi 5)
+- Downgraded from IDF v6.1.0 to v5.5.2 for compatibility with deployed devices
 - Branch renamed from `master` to `main`
 - Docs created: `docs/INSTALL.md`, `docs/USAGE.md`, `docs/CHEATSHEET.md`

docs/CHEATSHEET.md

@@ -19,9 +19,6 @@ idf.py -p /dev/ttyUSB0 monitor          # Serial monitor (Ctrl+] to exit)
 idf.py -p /dev/ttyUSB0 flash monitor    # Flash + monitor combined
 idf.py fullclean                        # Clean build directory
 idf.py reconfigure                      # Re-fetch managed components
-
-# IDF v6.1 workaround (after clean/reconfigure)
-ln -s 6.0 managed_components/espressif__esp_csi_gain_ctrl/6.1
 ```
 
 ## Deployed Sensors
@@ -82,7 +79,7 @@ secondary_channel,timestamp,ant,sig_len,rx_state,len,first_word,"[I,Q,...]"
 
 | Path | Contents |
 |------|----------|
-| `~/esp/esp-idf/` | ESP-IDF v6.1.0 |
+| `~/esp/esp-idf/` | ESP-IDF v5.5.2 |
 | `~/esp/esp-csi/` | Original esp-csi examples |
 | `~/.espressif/tools/` | Xtensa toolchain |
 

docs/INSTALL.md

@@ -4,12 +4,12 @@
 
 | Component | Version | Location |
 |-----------|---------|----------|
-| ESP-IDF | v6.1.0 | `~/esp/esp-idf/` |
+| ESP-IDF | v5.5.2 | `~/esp/esp-idf/` |
 | esp-csi | latest | `~/esp/esp-csi/` (reference only) |
-| Xtensa toolchain | GCC 15.2.0 | `~/.espressif/tools/` |
+| Xtensa toolchain | (bundled) | `~/.espressif/tools/` |
 | Python | 3.13+ | ESP-IDF venv |
 
-**Note:** No RISC-V toolchain installed. Only ESP32 (Xtensa) targets are supported. For ESP32-C3/C5/C6, run `~/esp/esp-idf/install.sh` with the appropriate target first.
+**Note:** Only ESP32 (Xtensa) target is installed. For ESP32-C3/C5/C6, run `~/esp/esp-idf/install.sh` with the appropriate target first.
 
 ## Setup
 
@@ -54,17 +54,6 @@ idf.py build
 
 Build output goes to `build/` (excluded by `.gitignore`). External component `esp_csi_gain_ctrl` is fetched automatically to `managed_components/`.
 
-### ESP-IDF v6.1 Workaround
-
-The `esp_csi_gain_ctrl` component (v0.1.4) only ships prebuilt libraries up to ESP-IDF v6.0. On ESP-IDF v6.1+, the build fails with a missing `.a` file. Fix by symlinking:
-
-```bash
-cd managed_components/espressif__esp_csi_gain_ctrl
-ln -s 6.0 6.1
-```
-
-This is needed after every `idf.py fullclean` or component re-fetch. The v6.0 library is ABI-compatible with v6.1.
-
 ## Flash
 
 ### Connect ESP32