+<li><tt class="docutils literal"><span class="pre">@includes</span></tt>: This array contains the TinyOS search path, i.e., the
+directories which will be passed to nescc (the TinyOS-agnostic nesC
+compiler) as <tt class="docutils literal"><span class="pre">-I</span></tt> arguments. You MUST add to <tt class="docutils literal"><span class="pre">@includes</span></tt> any
+directories needed to compile this sensor board's components. For
+instance, if your sensor boards depends on support code found in
+<tt class="docutils literal"><span class="pre">tos/chips/sht11</span></tt>, you would add <tt class="docutils literal"><span class="pre">"%T/chips/sht11"</span></tt> to <tt class="docutils literal"><span class="pre">@includes</span></tt>.</li>
+<li><tt class="docutils literal"><span class="pre">@new_args</span></tt>: This is the array of arguments which will be passed to
+nescc. You MUST add any arguments other than <tt class="docutils literal"><span class="pre">-I</span></tt> that are necessary
+to compile your sensor board components to <tt class="docutils literal"><span class="pre">@new_args</span></tt>.</li>
+</ul>
+<p>If a sensor is associated with a platform <cite>P</cite> rather than a sensor
+board, then that platform MUST ensure that, when compiling for
+platform <cite>P</cite>, all directories needed to compile that sensor's
+component are added to the TinyOS search path (see <a class="citation-reference" href="#tep131" id="id8" name="id8">[TEP131]</a> for
+information on how to set up a TinyOS platform).</p>
+</div>
+<div class="section">
+<h2><a id="sensor-components" name="sensor-components">4.2 Sensor Components</a></h2>
+<p>A particular sensor is typically supported by many components,
+including the HIL and HAL components from Sections 2 and 3, A/D
+conversion components (for analog sensors), digital bus components
+(e.g., SPI, for digital sensors), system services (timers, resource
+and power management, ...), glue components (to connect sensors,
+sensor boards and platforms), etc. These components can be divided
+into three classes: sensorboard-dependent, platform-dependent and
+platform-independent. The sensorboard and platform MUST ensure
+(Section 4.1) that all these components can be found at compile-time.</p>
+<p>Because the same physical sensor can be used on many platforms or
+sensor boards, and attached in many different ways, to maximize code
+reuse the organization of sensor drivers SHOULD reflect the
+distinction between sensor and sensor interconnect. The sensor
+components SHOULD be platform-independent, while the sensor
+interconnect components are typically sensorboard or
+platform-dependent. However, some sensors (e.g. analong sensors) will
+not have a sufficiently large amount of platform-independent logic to
+justify creating platform-independent components.</p>
+<p>The following guidelines specify how to organize sensor and sensor
+interconnect components within TinyOS's directory hierarchy. These
+guidelines are only relevant to components that are part of the core
+source tree. The string <tt class="docutils literal"><span class="pre"><sensor></span></tt> SHOULD reflect the make and model
+of the sensor device.</p>
+<ul class="simple">
+<li>Platform-independent sensor components that exist as part of a
+larger chip, like a MCU internal voltage sensor, SHOULD be placed in
+a subdirectory of the chip's directory
+<tt class="docutils literal"><span class="pre">tos/<chip>/sensors/<sensor></span></tt>.</li>
+<li>Other platform-independent sensor components SHOULD be placed
+in <tt class="docutils literal"><span class="pre">tos/chips/<sensor></span></tt>.</li>
+<li>Sensorboard-dependent sensor and sensor interconnect components
+SHOULD be placed either in the <tt class="docutils literal"><span class="pre"><sensorboard></span></tt> directory or in a
+<tt class="docutils literal"><span class="pre"><sensorboard>/chips/<sensor></span></tt> directory.</li>
+<li>Platform-dependent sensor and sensor interconnect components SHOULD
+be placed in <tt class="docutils literal"><span class="pre">tos/<platform>/chips/<sensor></span></tt>.</li>