docs/solutions/reference-designs/eval-cn0575-rpiz/sample_application: Add blinky sample application

- Add blinky sample application page with instructions for the user to recreate the example at home
- Provide images that showcase the way this application functions
- Add images with the system setup

Signed-off-by: Evelyn Plesca <evelyn-iulia.plesca@analog.com>

Author: plescaevelyn

docs/solutions/reference-designs/eval-cn0575-rpiz/index.rst

@@ -479,6 +479,15 @@ Hardware Registration
    Receive software update notifications, documentation updates, view the latest
    videos, and more when you :adi:`register <EVAL-CN0575-RPIZ?&v=RevC>` your hardware.
 
+Sample Application
+------------------
+
+.. toctree::
+   :maxdepth: 2
+   :glob:
+
+   */index
+
 Help and Support
 -------------------
 

docs/solutions/reference-designs/eval-cn0575-rpiz/sample_application/eval-cn0575-rpiz-sample-application-blinky-system.png

@@ -0,0 +1,243 @@
+Blinky Application
+=================
+
+This sample application demonstrates a basic Blinky application using two :adi:`EVAL-CN0575-RPIZ` HATs,
+an :adi:`AD-RPI-T1LPSE-SL` HAT as a communication interface, and three Raspberry Pi computers. 
+These are set up in a parent-child configuration, where the :adi:`AD-RPI-T1LPSE-SL` HAT acts as the parent device, 
+and the two :adi:`EVAL-CN0575-RPIZ` HATs act as child devices.
+The application toggles the on-board LED of a :adi:`EVAL-CN0575-RPIZ` HAT when the button is pressed on the 
+other :adi:`EVAL-CN0575-RPIZ` HAT and vice versa.
+
+Prerequisites
+-------------
+
+- Python 3.8 or newer (3.8–3.11 tested with pyadi-iio).  
+  Ensure that a compatible version is installed on your system before continuing.  
+  Older versions (<3.8) may not work reliably with pyadi-iio.
+
+- Git command-line tools installed.
+
+- Three Raspberry Pi computers with :adi:`Kuiper 2` image installed.
+  Follow the instructions in the `Kuiper 2 User Guide <https://github.com/analogdevicesinc/adi-kuiper-gen/releases>`_
+  to prepare the Raspberry Pi.
+
+Hardware Setup
+--------------
+
+.. figure:: eval-cn0575-rpiz-sample-application-blinky-system.png
+   :align: center
+   :width: 500
+
+   Hardware Setup for Blinky Application
+
+**Equipment Needed**
+
+- 1x :adi:`AD-RPI-T1LPSE-SL` Board
+
+- 2x :adi:`EVAL-CN0575-RPIZ` Boards
+
+- 3x Raspberry Pi 5 computers running Kuiper 2
+
+- 1x USB Type-C Power Supply (15V, 3A)
+
+- 2x T1L Cables
+
+**Setup Procedure**
+
+1. Connect the :adi:`AD-RPI-T1LPSE-SL` board and both :adi:`EVAL-CN0575-RPIZ` boards to Raspberry Pis via the 40-pin header.
+
+2. Connect the power supply to the :adi:`AD-RPI-T1LPSE-SL` HAT using the USB Type-C port.
+
+3. Connect the two Raspberry Pi that are interfaced with the :adi:`EVAL-CN0575-RPIZ` HATs to the :adi:`AD-RPI-T1LPSE-SL` HAT 
+   using T1L cables.
+
+5. Power on the Raspberry Pi computers.
+
+Software Setup
+--------------
+
+When running commands with *sudo*, you might be prompted to enter the password for the **analog** user.
+If you have not changed it, the default password is **analog**.
+
+Repository Cloning
+~~~~~~~~~~~~~~~~~~
+
+1. Clone the repository on both Raspberry Pi computers:
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ git clone https://github.com/analogdevicesinc/pyadi-iio.git
+      $ cd pyadi-iio
+
+2. Install Python dependencies and open a virtual environment:
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ python3 -m venv ./venv
+      $ source venv/bin/activate
+      $ pip install -e .
+
+Applying Overlays
+~~~~~~~~~~~~~~~~~
+
+Overlays are required to enable the proper device tree configurations for the HATs.
+
+In order to apply the overlays, open a terminal on each Raspberry Pi and follow these steps:
+
+1. For the parent Raspberry Pi:
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ sudo tee -a /boot/firmware/config.txt <<'EOF'
+         dtoverlay=rpi-t1lpse-apl
+         dtoverlay=rpi-t1lpse-class12
+         EOF
+
+2. For each child Raspberry Pi:
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ sudo tee -a /boot/firmware/config.txt <<'EOF'
+         dtoverlay=rpi-cn0575
+         EOF
+
+Reboot the Raspberry Pi computers to apply the changes:
+
+   .. shell::
+      :user: analog
+      :group: analog:
+      :show-user:
+
+      $ sudo reboot
+
+Hostname Setup
+~~~~~~~~~~~~~~
+
+Each Raspberry Pi must have a unique hostname to avoid network conflicts.
+
+1. On each Raspberry Pi, open a terminal and enter the following command to edit the hostname file.
+
+   Keep in mind that *<new_hostname>* should be replaced with a unique name for each Raspberry Pi. We used 
+   **analog** for the parent Raspberry Pi, **cn0575a** for the first child Raspberry Pi, and **cn0575b** for the second child Raspberry Pi.
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ hostnamectl set-hostname <new_hostname>
+
+Network Setup
+~~~~~~~~~~~~~
+
+Each Raspberry Pi must be configured with a static IP address to ensure reliable communication.
+
+For our demo, we will use the following IP addresses:
+
+- The Raspberry Pi with :adi:`AD-RPI-T1LPSE-SL` HAT (parent): **192.168.10.1/25** on **eth1** and **192.168.10.129/25** on **eth2**
+
+- First Raspberry Pi with :adi:`EVAL-CN0575-RPIZ` HAT (first child): **192.168.10.2/25** on **eth1**
+
+- Second Raspberry Pi with :adi:`EVAL-CN0575-RPIZ` HAT (second child): **192.168.10.130/25** on **eth1**
+
+Open the terminal and write the following commands:
+
+1. On the parent Raspberry Pi, with the :adi:`AD-RPI-T1LPSE-SL` HAT:
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ sudo nmcli con add type ethernet ifname eth1 con-name t1l-cn0575a \
+           ipv4.method manual ipv4.addresses 192.168.10.1/25 \
+           connection.autoconnect yes 
+      $ sudo nmcli con add type ethernet ifname eth2 con-name t1l-cn0575b \
+            ipv4.method manual ipv4.addresses 192.168.10.129/25 \
+            connection.autoconnect yes 
+      $ sudo nmcli con up t1l-cn0575a
+      $ sudo nmcli con up t1l-cn0575b
+
+2. On the first child Raspberry Pi, with the first :adi:`EVAL-CN0575-RPIZ` HAT:
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ sudo nmcli con add type ethernet ifname eth1 con-name t1l-master \
+         ipv4.method manual ipv4.addresses 192.168.10.2/25 \
+         connection.autoconnect yes
+      $ sudo nmcli con up t1l-master
+
+3. On the second child Raspberry Pi, with the second :adi:`EVAL-CN0575-RPIZ` HAT:
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ sudo nmcli con add type ethernet ifname eth1 con-name t1l-master \
+         ipv4.method manual ipv4.addresses 192.168.10.130/25 \
+         connection.autoconnect yes
+      $ sudo nmcli con up t1l-master
+
+4. Reboot all the Raspberry Pi computers to apply the changes:
+   
+   .. shell::
+      :user: analog
+      :group: analog:
+      :show-user:
+
+      $ sudo reboot
+
+5. Verify that the new connections are active on each Raspberry Pi:
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ nmcli connection show
+
+   .. figure:: eval-cn0575-rpiz-sample-application-nm-nmcli-conn-show.png
+      :align: center
+      :width: 500
+
+      Example of active NetworkManager connections
+
+Application Execution
+~~~~~~~~~~~~~~~~~~~~~
+
+When executed, the demo continously reads the state of the button the :adi:`CN0575` HAT and 
+toggles the LED on the other :adi:`CN0575` HAT if pressed and vice versa. The code is run on the 
+parent only, which communicates with both child devices using *libiio*.
+
+Run the application the parent Raspberry Pi only, which will handle communication with both child devices.
+
+   .. shell::
+      :user: analog
+      :group: analog
+      :show-user:
+
+      $ cd examples/cn0575
+      $ source venv/bin/activate
+      $ python3 cn0591_2x_cn0575_button_blinky.py
+
+   .. figure:: eval-cn0575-rpiz-sample-application-terminal-result.gif
+      :align: center
+      :width: 500
+
+      Running Blinky Application with Button Presses