bar-link">
 <span class="menu-text">1.6 Displaying ‚ÄúHello World‚Äù on OLED</span></a>
  </div>
</li>
      </ul>
  </li>
        <li class="sidebar-item sidebar-item-section">
      <div class="sidebar-item-container"> 
            <a href="./chapter_2.html" class="sidebar-item-text sidebar-link">
 <span class="menu-text">Chapter 2: Project Practice for Beginners - Introduction to Prototype Design</span></a>
          <a class="sidebar-item-toggle text-start" data-bs-toggle="collapse" data-bs-targ