Revert "docs: update README"

This reverts commit 33f3806.

Author: casaroli

README.md

@@ -2,39 +2,28 @@
 
 The Ocre SDK provides a modular C-based API for building portable embedded applications that compile to WebAssembly. It includes both headers and source files, enabling flexible integration across platforms. This repository also contains a wide range of generic and board-specific examples that demonstrate real-world use cases.
 
-All examples are designed to be executed inside the [Ocre Runtime](https://github.com/project-ocre/ocre-runtime), a lightweight WASI-compatible runtime tailored for embedded-style workloads.
+All examples are designed to be built using [wasi-sdk](https://github.com/WebAssembly/wasi-sdk) and executed inside the [Ocre Runtime](https://github.com/project-ocre/ocre-runtime), a lightweight WASI-compatible runtime tailored for embedded-style workloads.
 
 ## Repository Structure
-
 ```
   ├── ocre-api                  # Core SDK: headers + sources
   ├── generic                   # Platform-independent examples
-  │   ├── blinky, echo-server, filesystem, etc.
-  │   └── build folders per sample
-  ├── board_specific            # Hardware-targeted examples
-  │   ├── arduino_portenta_h7
+  │   ├── blinky, echo-server, filesystem, etc. 
+  │   └── build folders per sample 
+  ├── board_specific            # Hardware-targeted examples 
+  │   ├── arduino_portenta_h7 
   │   └── b_u585i_iot02a
   ├── testing                   # Testing and potentially faulty images.
-  │   └── return0, return1, pthread, etc.
+  │   └── return0, return1, pthread, etc. 
   ├── wasm-micro-runtime        # External module
 ```
 
-## Getting Started
-
-### System requirements
+Each sample includes:
+- CMakeLists.txt for build configuration
+- A build/ directory (created during compilation)
+- Optional subfolders like src/, fs/, or IMU/ depending on the sample
 
-To build the samples, you need LLVM, LLD, Clang 12+, wasm32 runtime libraries. You also need cmake, make and **\***. Install all on an Ubuntu 22 with:
-
-```sh
-sudo apt install \
-    cmake \
-    clang \
-    libclang-rt-dev-wasm32 \
-    lld \
-    llvm
-```
-
-Alternatively, you can use the Ocre devcontainer. Check Ocre documentation for more information.
+## Getting Started
 
 ### Clone the Repository
 
@@ -50,65 +39,40 @@ Or add the SDK as a submodule to your own project:
 git submodule add https://github.com/project-ocre/ocre-sdk.git
 ```
 
-## Set up Sysroot
+Make sure the ocre-api folder is accessible to your build system.
 
-The default sysroot can be set up automatically. From the root of this repository:
+## Building with wasi-sdk
+All examples are designed to compile to .wasm using [wasi-sdk](https://github.com/WebAssembly/wasi-sdk).
 
-```sh
-mkdir build
-cd build
-cmake ..
-make sysroot
-```
+> **Note:** By default, we expect the WASI SDK toolchain file to be located at:
+>
+> `/opt/wasi-sdk/share/cmake/wasi-sdk.cmake`
+>
+> This is typically set in each sample's `CMakeLists.txt`. You can modify this path as needed for your environment.
 
-The `sysroot` Make target will download the wasi-sysroot, then compile `lib_socket_ext` and `ocre_api`, and populate them into the `sysroot` directory on the root of this repository.
-
-It is also possible to specify a different WAMR root, used for building `lib_socket_ext`, through the `WAMR_ROOT` CMake variable, if you do not want to use the included git submodule:
-
-```sh
-cmake .. -DWAMR_ROOT=~/ocre/wasm-micro-runtime
-```
-
-## Build Samples
-
-### From the ocre-sdk build directory
-
-Alternatively, the `all` Make target will build most of the generic samples and testing containers:
-
-```sh
-make
-```
+### Build Instructions
+Each sample can be built independently. Here's a generic flow
 
-You can also build a specific sample, for example:
-
-```sh
-make hello-world
-```
-
-The built files are stord in the `dist` directory inside the current build directory:
-
-```sh
-ls dist
+```bash
+cd generic/blinky
+mkdir -p build && cd build
+cmake ..
+cmake --build .
 ```
+This will generate a .wasm binary in the build/ directory.
 
-### From each sample's directory
+Repeat the same process for any other sample—whether under generic/ or board_specific/
 
-Assumming, you already have the sysroot installed into the `sysroot` directory, it is possible to build each sample from their own directory, for example:
+## Running with Ocre Runtime
+All compiled .wasm samples are compatible with the [Ocre Runtime](https://github.com/project-ocre/ocre-runtime), which provides a lightweight execution environment for WASI modules.
 
-```sh
-cd generic/hello-world
-mkdir build
-cd build
-cmake ..
-make
+Example:
+```bash
+app build/hello-world.wasm
 ```
 
-The built file is stored in the current build directory.
-
 ## Example Categories
-
 ### Generic Samples
-
 - blinky
 - hello-world
 - echo-server
@@ -117,20 +81,15 @@ The built file is stored in the current build directory.
 - messaging: publisher, subscriber, multipublisher-subscriber
 - modbus-client
 - sensor-rng
-
 ### Board-Specific Samples
-
 - arduino_portenta_h7: blinky-h7
 - b_u585i_iot02a: sensor, sensor-IMU, modbus-server, blinky-xmas, blinky-u585, blinky-button
-  These demonstrate hardware-specific integrations while still leveraging the common ocre-api.
-
+These demonstrate hardware-specific integrations while still leveraging the common ocre-api.
 ## SDK Highlights
-
 - Header and source-based SDK (ocre-api)
 - Modular CMake-based build system
 - Runtime execution via Ocre Runtime
 - Extensible for new boards and applications
 
 ## Contributing
-
 Want to add a new board or example? Fork the repo, create your sample under generic/ or board_specific/, and submit a pull request. Contributions are welcome