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+<meta name="generator" content="Docutils 0.4: http://docutils.sourceforge.net/" />
<title>Sensors and Sensor Boards</title>
-<meta name="author" content="David Gay, Phil Levis, Wei Hong, Joe Polastre, and Gilman Tolle" />
+<meta name="author" content="David Gay, Philip Levis, Wei Hong, Joe Polastre, and Gilman Tolle" />
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+<div class="document" id="sensors-and-sensor-boards">
<h1 class="title">Sensors and Sensor Boards</h1>
<table class="docinfo" frame="void" rules="none">
<col class="docinfo-name" />
<tr class="field"><th class="docinfo-name">Type:</th><td class="field-body">Documentary</td>
</tr>
<tr><th class="docinfo-name">Status:</th>
-<td>Draft</td></tr>
+<td>Final</td></tr>
<tr class="field"><th class="docinfo-name">TinyOS-Version:</th><td class="field-body">2.x</td>
</tr>
<tr><th class="docinfo-name">Author:</th>
-<td>David Gay, Phil Levis, Wei Hong, Joe Polastre, and Gilman Tolle</td></tr>
-<tr class="field"><th class="docinfo-name">Draft-Created:</th><td class="field-body">10-Jun-2006</td>
-</tr>
-<tr class="field"><th class="docinfo-name">Draft-Discuss:</th><td class="field-body">TinyOS Developer List <tinyos-devel at mail.millennium.berkeley.edu></td>
-</tr>
+<td>David Gay, Philip Levis, Wei Hong, Joe Polastre, and Gilman Tolle</td></tr>
</tbody>
</table>
-<div class="document" id="sensors-and-sensor-boards">
<div class="note">
<p class="first admonition-title">Note</p>
<p class="last">This memo documents a part of TinyOS for the TinyOS Community, and
of this memo is unlimited. This memo is in full compliance with
TEP 1.</p>
</div>
-<div class="section" id="abstract">
-<h1><a name="abstract">Abstract</a></h1>
+<div class="section">
+<h1><a id="abstract" name="abstract">Abstract</a></h1>
<p>This memo documents how sensor drivers are organized in TinyOS and how
sets of sensor drivers are combined into sensor boards and sensor
platforms, along with general principles followed by the components
that provide access to sensors.</p>
</div>
-<div class="section" id="principles">
-<h1><a name="principles">1. Principles</a></h1>
+<div class="section">
+<h1><a id="principles" name="principles">1. Principles</a></h1>
<p>This section describes the basic organization principles for sensor
drivers in TinyOS.</p>
<p>For background, a sensor can be attached to the microcontroller on a
reflect the specifc name of the sensor, and MAY provide a component
with a generic name for application authors who only care about the
general class of the sensor.</p>
-<p>This document takes no position on the meaning of the values returned
-by sensor drivers. They MAY be raw uninterpreted values or they MAY
-have some physical meaning. If a driver returns uninterpreted values,
-the driver MAY provide additional interfaces that would allow
-higher-level clients to obtain information needed to properly
-interpret the value.</p>
+<p>This document requires that sensor components specify the range (in
+bits) of values returned by sensor drivers, but takes no position on
+the meaning of these values. They MAY be raw uninterpreted values or
+they MAY have some physical meaning. If a driver returns uninterpreted
+values, the driver MAY provide additional interfaces that would allow
+higher-level clients to obtain information (e.g. calibration
+coefficients) needed to properly interpret the value.</p>
</div>
-<div class="section" id="sensor-hil-components">
-<h1><a name="sensor-hil-components">2. Sensor HIL Components</a></h1>
+<div class="section">
+<h1><a id="sensor-hil-components" name="sensor-hil-components">2. Sensor HIL Components</a></h1>
<p>A sensor HIL component MUST provide:</p>
<ul class="simple">
<li>One or more SID interfaces <a class="citation-reference" href="#tep114" id="id2" name="id2">[TEP114]</a>, for reading data.</li>
interface it corresponds to.</p>
<p>The getSignificantBits() call MUST return the number of significant
bits in the reading. For example, a sensor reading taken from a 12-bit
-ADC MUST return the value "12".</p>
+ADC would typically return the value 12 (it might return less if, e.g.,
+physical constraints limit the maximum A/D result to 10-bits).</p>
<p>Sensor driver components SHOULD be named according to the make and
model of the sensing device being presented. Using specific names
gives the developer the option to bind to a particular sensor, which
}
</pre>
</div>
-<div class="section" id="sensor-hal-components">
-<h1><a name="sensor-hal-components">3. Sensor HAL Components</a></h1>
+<div class="section">
+<h1><a id="sensor-hal-components" name="sensor-hal-components">3. Sensor HAL Components</a></h1>
<p>Sensors with a richer interface than would be supported by the SID
interfaces MAY provide a HAL component in addition to a HIL
component.</p>
<li>A <cite>StdControl</cite> or <cite>SplitControl</cite> interface for manual power
management by the user, following the conventions described in
<a class="citation-reference" href="#tep115" id="id5" name="id5">[TEP115]</a>.</li>
-<li>A Resource[] interface for requesting access to the device and
-possibly performing automated power management.</li>
-<li>Any other interfaces needed to control the device.</li>
+<li>A <cite>Resource</cite> interface for requesting access to the device and
+possibly performing automated power management, following
+the conventions described in <a class="citation-reference" href="#tep108" id="id6" name="id6">[TEP108]</a> and <a class="citation-reference" href="#tep115" id="id7" name="id7">[TEP115]</a>.</li>
+<li>Any other interfaces needed to control the device, e.g., to
+read or write calibration coefficients.</li>
</ul>
<p>For example:</p>
<pre class="literal-block">
}
</pre>
</div>
-<div class="section" id="directory-organization-guidelines">
-<h1><a name="directory-organization-guidelines">4. Directory Organization Guidelines</a></h1>
-<p>Because the same physical sensor can be attached to TinyOS platforms
-in many different ways, the organization of sensor drivers SHOULD
-reflect the distinction between sensor and sensor interconnect.</p>
-<p>Sensor components commonly exist at three levels:
-platform-independent, sensorboard-dependent, and
-platform-dependent. Factoring a sensor driver into these three pieces
-allows for greater code reuse when the same sensor is attached to
-different sensorboards or platforms.</p>
-<p>Platform-independent sensor driver components for a particular sensor,
-like protocol logic, when in the core TinyOS 2.x source tree, SHOULD
-be placed into "tos/chips/<sensor>", where <sensor> reflects the make
-and model of the sensor device being supported. When not a part of the
-core source tree, this directory can be placed anywhere as long as the
-nesC compiler recieves a <cite>-I</cite> directive pointing to the sensor's
-directory. However, not all sensors have a sufficiently large amount
-of platform-independent logic to justify a separate "chips"
-directory. Sensor chips are more likely to be digital sensors than
-analog sensors, for example.</p>
-<p>A sensor board is a collection of sensor components with a fixed name,
-intended for attachment to multiple platforms. Each sensor board MUST
-have its own directory named <sensorboard>. Default TinyOS 2.x sensor
-boards are placed in "tos/sensorboards/<sensorboard>", but sensor
-board directories can be placed anywhere as long as the nesC compiler
-receives a <cite>-I</cite> directive pointing to the sensor board's directory.</p>
-<p>Both sensors and sensor boards MUST have unique names. Case is
-significant, but two sensor boards MUST differ in more than case. This
-is necessary to support platforms where filename case differences are
-not significant.</p>
-<p>Each sensor board directory MUST contain a <cite>.sensor</cite> file. This file
-is a perl script which gets executed as part of the <cite>ncc</cite> nesC
-compiler frontend. It can add or modify any compile-time options
-necessary for a particular sensor board. It MAY modify the following
-perl variables, and MUST NOT modify any others:</p>
+<div class="section">
+<h1><a id="sensor-component-organization-and-compiler-interaction-guidelines" name="sensor-component-organization-and-compiler-interaction-guidelines">4. Sensor Component Organization and Compiler Interaction Guidelines</a></h1>
+<p>Sensors are associated either with a particular sensor board or with a
+particular platform. Both sensors and sensor boards MUST have unique
+names. Case is significant, but two sensor (or sensor board) names
+MUST differ in more than case. This is necessary to support platforms
+where filename case differences are not significant.</p>
+<p>Each sensor board MUST have its own directory whose name is the sensor
+board's unique name (referred to as <sensorboard> in the rest of this
+section). Default TinyOS 2.x sensor boards are placed in
+<tt class="docutils literal"><span class="pre">tos/sensorboards/<sensorboard></span></tt>, but sensor board directories can be
+placed anywhere as long as the nesC compiler receives a <tt class="docutils literal"><span class="pre">-I</span></tt> directive
+pointing to the sensor board's directory. Each sensor board directory
+MUST contain a <tt class="docutils literal"><span class="pre">.sensor</span></tt> file (described below). If the
+sensor board wishes to define any C types or constants, it SHOULD
+place these in a file named <tt class="docutils literal"><span class="pre"><sensorboard>.h</span></tt> in the sensor board's
+directory.</p>
+<p>A sensor board MAY contain components that override the default TinyOS
+<em>demo sensors</em>. This allows the sensor board to easily be used with
+TinyOS sample applications that use the demo sensors. If a sensor
+board wishes to override the default demo sensor:</p>
+<ul>
+<li><p class="first">It MUST provide a generic component named <tt class="docutils literal"><span class="pre">DemoSensorC</span></tt> with the
+following signature:</p>
+<pre class="literal-block">
+provides interface Read<uint16_t>;
+provides interface DeviceMetadata;
+</pre>
+</li>
+<li><p class="first">It MAY provide a generic component named <tt class="docutils literal"><span class="pre">DemoSensorNowC</span></tt> with the
+following signature:</p>
+<pre class="literal-block">
+provides interface ReadNow<uint16_t>;
+provides interface DeviceMetadata;
+</pre>
+<p>This component SHOULD sample the same sensor as <tt class="docutils literal"><span class="pre">DemoSensorC</span></tt>.</p>
+</li>
+<li><p class="first">It MAY provide a generic component named <tt class="docutils literal"><span class="pre">DemoSensorStreamC</span></tt> with the
+following signature:</p>
+<pre class="literal-block">
+provides interface ReadStream<uint16_t>;
+provides interface DeviceMetadata;
+</pre>
+<p>This component SHOULD sample the same sensor as <tt class="docutils literal"><span class="pre">DemoSensorC</span></tt>.</p>
+</li>
+</ul>
+<p>These components MUST be an alias for one of the sensor board's usual
+sensors, though they change the precision of the sensor if necessary.
+For instance, if <tt class="docutils literal"><span class="pre">DemoSensorC</span></tt> is an alias for a 20-bit sensor that
+provides a <tt class="docutils literal"><span class="pre">Read<uint32_t></span></tt> interface, <tt class="docutils literal"><span class="pre">DemoSensorC</span></tt> would still
+provide <tt class="docutils literal"><span class="pre">Read<uint16_t></span></tt> and would include code to reduce the
+precision of the aliased sensor.</p>
+<div class="section">
+<h2><a id="compiler-interaction" name="compiler-interaction">4.1 Compiler Interaction</a></h2>
+<p>When the <tt class="docutils literal"><span class="pre">ncc</span></tt> nesC compiler frontend is passed a <tt class="docutils literal"><span class="pre">-board=X</span></tt> option,
+it executes the <tt class="docutils literal"><span class="pre">.sensor</span></tt> file found in the sensor board directory
+<tt class="docutils literal"><span class="pre">X</span></tt>. This file is a perl script which can add or modify any
+compile-time options necessary for the sensor board. It MAY modify the
+following perl variables, and MUST NOT modify any others:</p>
+<ul class="simple">
+<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>@new_args: This is the array of arguments which will be passed to
-nescc. For instance, you might add an include directive to @new_args
-with push @new_args, <cite>-Isomedir</cite>. This could be used to include
-subdirectories.</li>
-<li>@commonboards: This can be set to a list of sensor board names which
-will be added to the include path list. These sensor boards MUST be
-in tinyos-2.x/tos/sensorboards.</li>
+<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>
</ul>
-<p>If the sensor board wishes to define any C types or constants, it
-SHOULD place these in a file named <sensorboard>.h in the sensor
-board's directory.</p>
-<p>A sensor board directory MAY contain a "chips" directory, with
-subdirectories for each of the sensors connected to the sensor board.
-If a "chips" subdirectory is used, sensorboard-dependent driver
-components needed to connect platform-independent logic to a
-particular attachment for that sensor SHOULD be placed in
-"<sensorboard>/chips/<sensor>".</p>
-<p>Components needed to connect the platform-independent sensor driver
-components or sensorboard-dependent components to the hardware
-resources available on a particular platform SHOULD be placed in
-"tos/<platform>/chips/<sensor>". In addition, components for a sensor
-that only exists on a particular platform SHOULD be placed in a such a
-directory.</p>
-<p>Sensors 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. "tos/<chip>/sensors/<sensor>".</p>
-<p>The <cite>.platform</cite> and <cite>.sensor</cite> files need to include enough <cite>-I</cite>
-directives to locate all of the necessary components needed to support
-the sensors on a platform and/or sensorboard.</p>
-<p>All of these directory organization guidelines are only intended for
-code that will enter the core source tree. In general, sensor
-components can be placed anywhere as long as the nesC compiler
-receives enough <cite>-I</cite> directives to locate all of the necessary pieces.</p>
</div>
-<div class="section" id="authors-addresses">
-<h1><a name="authors-addresses">5. Authors' Addresses</a></h1>
+</div>
+<div class="section">
+<h1><a id="authors-addresses" name="authors-addresses">5. Authors' Addresses</a></h1>
<div class="line-block">
<div class="line">David Gay</div>
<div class="line">2150 Shattuck Ave, Suite 1300</div>
<div class="line">email - <a class="reference" href="mailto:gtolle@archrock.com">gtolle@archrock.com</a></div>
</div>
</div>
-<div class="section" id="citations">
-<h1><a name="citations">6. Citations</a></h1>
+<div class="section">
+<h1><a id="citations" name="citations">6. Citations</a></h1>
<table class="docutils citation" frame="void" id="tep2" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id1" name="tep2">[TEP2]</a></td><td>TEP 2: Hardware Abstraction Architecture</td></tr>
</tbody>
</table>
+<table class="docutils citation" frame="void" id="tep108" rules="none">
+<colgroup><col class="label" /><col /></colgroup>
+<tbody valign="top">
+<tr><td class="label"><a class="fn-backref" href="#id6" name="tep108">[TEP108]</a></td><td>TEP 108: Resource Arbitration</td></tr>
+</tbody>
+</table>
<table class="docutils citation" frame="void" id="tep114" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<table class="docutils citation" frame="void" id="tep115" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
-<tr><td class="label"><a name="tep115">[TEP115]</a></td><td><em>(<a class="fn-backref" href="#id4">1</a>, <a class="fn-backref" href="#id5">2</a>)</em> TEP 115: Power Management of Non-Virtualized Devices</td></tr>
+<tr><td class="label"><a name="tep115">[TEP115]</a></td><td><em>(<a class="fn-backref" href="#id4">1</a>, <a class="fn-backref" href="#id5">2</a>, <a class="fn-backref" href="#id7">3</a>)</em> TEP 115: Power Management of Non-Virtualized Devices</td></tr>
+</tbody>
+</table>
+<table class="docutils citation" frame="void" id="tep131" rules="none">
+<colgroup><col class="label" /><col /></colgroup>
+<tbody valign="top">
+<tr><td class="label"><a class="fn-backref" href="#id8" name="tep131">[TEP131]</a></td><td>TEP 131: Creating a New Platform for TinyOS 2.x</td></tr>
</tbody>
</table>
</div>
-<div class="section" id="appendix-a-sensor-driver-examples">
-<h1><a name="appendix-a-sensor-driver-examples">Appendix A: Sensor Driver Examples</a></h1>
-<div class="section" id="analog-adc-connected-sensor">
-<h2><a name="analog-adc-connected-sensor">1. Analog ADC-Connected Sensor</a></h2>
+<div class="section">
+<h1><a id="appendix-a-sensor-driver-examples" name="appendix-a-sensor-driver-examples">Appendix A: Sensor Driver Examples</a></h1>
+<div class="section">
+<h2><a id="analog-adc-connected-sensor" name="analog-adc-connected-sensor">1. Analog ADC-Connected Sensor</a></h2>
<p>The Analog sensor requires two components</p>
<ul class="simple">
<li>a component to present the sensor itself (HamamatsuS1087ParC)</li>
<pre class="literal-block">
tos/platforms/telosa/chips/s1087/HamamatsuS1087ParC.nc
+// HIL for the HamamatsuS1087 analog photodiode sensor
generic configuration HamamatsuS1087ParC() {
provides interface Read<uint16_t>;
provides interface ReadStream<uint16_t>;
provides interface DeviceMetadata;
}
implementation {
+ // Create a new A/D client and connect it to the Hamamatsu S1087 A/D
+ // parameters
components new AdcReadClientC();
Read = AdcReadClientC;
#include "Msp430Adc12.h"
+// A/D parameters for the Hamamatsu - see the MSP430 A/D converter manual,
+// Hamamatsu specification, Telos hardware schematic and TinyOS MSP430
+// A/D converter component specifications for the explanation of these
+// parameters
module HamamatsuS1087ParP {
provides interface AdcConfigure<const msp430adc12_channel_config_t*>;
provides interface DeviceMetadata;
}
implementation {
-
msp430adc12_channel_config_t config = {
inch: INPUT_CHANNEL_A4,
sref: REFERENCE_VREFplus_AVss,
}
</pre>
</div>
-<div class="section" id="binary-pin-connected-sensor">
-<h2><a name="binary-pin-connected-sensor">2. Binary Pin-Connected Sensor</a></h2>
+<div class="section">
+<h2><a id="binary-pin-connected-sensor" name="binary-pin-connected-sensor">2. Binary Pin-Connected Sensor</a></h2>
<p>The Binary sensor gets a bit more complex, because it has three
components:</p>
<ul class="simple">
<pre class="literal-block">
tos/platforms/telosa/UserButtonC.nc
+// HIL for the user button sensor on Telos-family motes
configuration UserButtonC {
- provides interface Get<bool>;
- provides interface Notify<bool>;
+ provides interface Get<bool>; // Get button status
+ provides interface Notify<bool>; // Get button-press notifications
provides interface DeviceMetadata;
}
implementation {
+ // Simply connect the button logic to the button HPL
components UserButtonLogicP;
Get = UserButtonLogicP;
Notify = UserButtonLogicP;
<pre class="literal-block">
tos/platforms/telosa/UserButtonLogicP.nc
+// Transform the low-level (GeneralIO and GpioInterrupt) interface to the
+// button to high-level SID interfaces
module UserButtonLogicP {
provides interface Get<bool>;
provides interface Notify<bool>;
provides interface DeviceMetadata;
uses interface GeneralIO;
- uses interface GpioInterrupt;
+ uses interface GpioInterrupt;
}
implementation {
norace bool m_pinHigh;
command error_t Notify.enable() {
call GeneralIO.makeInput();
+ // If the pin is high, we need to trigger on falling edge interrupt, and
+ // vice-versa
if ( call GeneralIO.get() ) {
m_pinHigh = TRUE;
return call GpioInterrupt.enableFallingEdge();
return call GpioInterrupt.disable();
}
+ // Button changed, signal user (in a task) and update interrupt detection
async event void GpioInterrupt.fired() {
call GpioInterrupt.disable();
task void sendEvent() {
bool pinHigh;
pinHigh = m_pinHigh;
-
+
signal Notify.notify( pinHigh );
-
+
if ( pinHigh ) {
call GpioInterrupt.enableFallingEdge();
} else {
<pre class="literal-block">
tos/platforms/telosa/HplUserButtonC.nc
+// HPL for the user button sensor on Telos-family motes - just provides
+// access to the I/O and interrupt control for the pin to which the
+// button is connected
configuration HplUserButtonC {
provides interface GeneralIO;
provides interface GpioInterrupt;
}
</pre>
</div>
-<div class="section" id="digital-bus-connected-sensor">
-<h2><a name="digital-bus-connected-sensor">3. Digital Bus-Connected Sensor</a></h2>
+<div class="section">
+<h2><a id="digital-bus-connected-sensor" name="digital-bus-connected-sensor">3. Digital Bus-Connected Sensor</a></h2>
<p>The Digital sensor is the most complex out of the set, and includes
six components:</p>
<ul class="simple">
<pre class="literal-block">
tos/platforms/telosa/chips/sht11/SensirionSht11C.nc
-generic configuration SensirionSht11C() {
+// HIL interface to Sensirion SHT11 temperature and humidity sensor
+generic configuration SensirionSht11C() {
provides interface Read<uint16_t> as Temperature;
provides interface DeviceMetadata as TemperatureDeviceMetadata;
provides interface Read<uint16_t> as Humidity;
provides interface DeviceMetadata as HumidityDeviceMetadata;
}
implementation {
+ // Instantiate the module providing the HIL interfaces
components new SensirionSht11ReaderP();
Temperature = SensirionSht11ReaderP.Temperature;
Humidity = SensirionSht11ReaderP.Humidity;
HumidityDeviceMetadata = SensirionSht11ReaderP.HumidityDeviceMetadata;
+ // And connect it to the HAL component for the Sensirion SHT11
components HalSensirionSht11C;
enum { TEMP_KEY = unique("Sht11.Resource") };
<pre class="literal-block">
tos/chips/sht11/SensirionSht11ReaderP.nc
+// Convert Sensirion SHT11 HAL to HIL interfaces for a single
+// client, performing automatic resource arbitration
generic module SensirionSht11ReaderP() {
provides interface Read<uint16_t> as Temperature;
provides interface DeviceMetadata as TemperatureDeviceMetadata;
provides interface Read<uint16_t> as Humidity;
provides interface DeviceMetadata as HumidityDeviceMetadata;
-
+
+ // Using separate resource interfaces for temperature and humidity allows
+ // temperature and humidity measurements to be requested simultaneously
+ // (if a single Resource interface was used, a request for temperature would
+ // prevent any humidity requests until the temperature measurement was complete)
uses interface Resource as TempResource;
uses interface Resource as HumResource;
uses interface SensirionSht11 as Sht11Temp;
}
implementation {
command error_t Temperature.read() {
- call TempResource.request();
- return SUCCESS;
+ // Start by requesting access to the SHT11
+ return call TempResource.request();
}
event void TempResource.granted() {
error_t result;
+ // If the HAL measurement fails, release the SHT11 and signal failure
if ((result = call Sht11Temp.measureTemperature()) != SUCCESS) {
call TempResource.release();
signal Temperature.readDone( result, 0 );
}
event void Sht11Temp.measureTemperatureDone( error_t result, uint16_t val ) {
+ // Release the SHT11 and signal the result
call TempResource.release();
signal Temperature.readDone( result, val );
}
command uint8_t TemperatureDeviceMetadata.getSignificantBits() { return 14; }
command error_t Humidity.read() {
- call HumResource.request();
- return SUCCESS;
+ // Start by requesting access to the SHT11
+ return call HumResource.request();
}
event void HumResource.granted() {
error_t result;
+ // If the HAL measurement fails, release the SHT11 and signal failure
if ((result = call Sht11Hum.measureHumidity()) != SUCCESS) {
call HumResource.release();
signal Humidity.readDone( result, 0 );
}
event void Sht11Hum.measureHumidityDone( error_t result, uint16_t val ) {
+ // Release the SHT11 and signal the result
call HumResource.release();
signal Humidity.readDone( result, val );
}
command uint8_t HumidityDeviceMetadata.getSignificantBits() { return 12; }
+ // Dummy handlers for unused portions of the HAL interface
event void Sht11Temp.resetDone( error_t result ) { }
event void Sht11Temp.measureHumidityDone( error_t result, uint16_t val ) { }
event void Sht11Temp.readStatusRegDone( error_t result, uint8_t val ) { }
event void Sht11Hum.readStatusRegDone( error_t result, uint8_t val ) { }
event void Sht11Hum.writeStatusRegDone( error_t result ) { }
+ // We need default handlers as a client may wire to only the Temperature
+ // sensor or only the Humidity sensor
default event void Temperature.readDone( error_t result, uint16_t val ) { }
default event void Humidity.readDone( error_t result, uint16_t val ) { }
}
<pre class="literal-block">
tos/platforms/telosa/chips/sht11/HalSensirionSht11C.nc
+// HAL interface to Sensirion SHT11 temperature and humidity sensor
configuration HalSensirionSht11C {
+ // The SHT11 HAL uses resource arbitration to allow the sensor to shared
+ // between multiple clients and for automatic power management (the SHT11
+ // is switched off when no clients are waiting to use it)
provides interface Resource[ uint8_t client ];
provides interface SensirionSht11[ uint8_t client ];
}
implementation {
+ // The HAL implementation logic
components new SensirionSht11LogicP();
SensirionSht11 = SensirionSht11LogicP;
+ // And it's wiring to the SHT11 HPL - the actual resource management is
+ // provided at the HPL layer
components HplSensirionSht11C;
Resource = HplSensirionSht11C.Resource;
SensirionSht11LogicP.DATA -> HplSensirionSht11C.DATA;
SensirionSht11LogicP.CLOCK -> HplSensirionSht11C.SCK;
SensirionSht11LogicP.InterruptDATA -> HplSensirionSht11C.InterruptDATA;
-
+
components new TimerMilliC();
SensirionSht11LogicP.Timer -> TimerMilliC;
<pre class="literal-block">
tos/platforms/telosa/chips/sht11/HplSensirionSht11C.nc
+// Low-level, platform-specific glue-code to access the SHT11 sensor found
+// on telos-family motes - here the HPL just provides resource management
+// and access to the SHT11 data, clock and interrupt pins
configuration HplSensirionSht11C {
provides interface Resource[ uint8_t id ];
provides interface GeneralIO as DATA;
provides interface GpioInterrupt as InterruptDATA;
}
implementation {
+ // Pins used to access the SHT11
components HplMsp430GeneralIOC;
-
+
components new Msp430GpioC() as DATAM;
DATAM -> HplMsp430GeneralIOC.Port15;
DATA = DATAM;
components new Msp430GpioC() as PWRM;
PWRM -> HplMsp430GeneralIOC.Port17;
+ // HPL logic for switching the SHT11 on and off
components HplSensirionSht11P;
HplSensirionSht11P.PWR -> PWRM;
HplSensirionSht11P.DATA -> DATAM;
InterruptDATAC.HplInterrupt -> HplMsp430InterruptC.Port15;
InterruptDATA = InterruptDATAC.Interrupt;
+ // The arbiter and power manager for the SHT11
components new FcfsArbiterC( "Sht11.Resource" ) as Arbiter;
Resource = Arbiter;
-
+
components new SplitControlPowerManagerC();
SplitControlPowerManagerC.SplitControl -> HplSensirionSht11P;
SplitControlPowerManagerC.ArbiterInit -> Arbiter.Init;
<pre class="literal-block">
tos/platforms/telosa/chips/sht11/HplSensirionSht11P.nc
+// Switch the SHT11 on and off, and handle the 11ms warmup delay
module HplSensirionSht11P {
+ // The SplitControl interface powers the SHT11 on or off (it's automatically
+ // called by the SHT11 power manager, see HplSensirionSht11C)
+ // We use a SplitControl interface as we need to wait 11ms for the sensor to
+ // warm up
provides interface SplitControl;
uses interface Timer<TMilli>;
uses interface GeneralIO as PWR;
task void stopTask();
command error_t SplitControl.start() {
+ // Power SHT11 on and wait for 11ms
call PWR.makeOutput();
call PWR.set();
call Timer.startOneShot( 11 );
return SUCCESS;
}
-
+
event void Timer.fired() {
signal SplitControl.startDone( SUCCESS );
}
command error_t SplitControl.stop() {
+ // Power the SHT11 off
call SCK.makeInput();
call SCK.clr();
call DATA.makeInput();
}
</pre>
</div>
+<div class="section">
+<h2><a id="mda100-sensor-board-directory-organization" name="mda100-sensor-board-directory-organization">4. MDA100 Sensor Board Directory Organization</a></h2>
+<p>Here we show the organization of the sensor board directory for the
+mica-family Xbow MDA100CA and MDA100CB sensor boards, which have
+temperature and light sensors. It is found in
+<tt class="docutils literal"><span class="pre">tos/sensorboards/mda100</span></tt>:</p>
+<pre class="literal-block">
+./tos/sensorboards/mda100:
+.sensor # Compiler configuration
+ArbitratedPhotoDeviceP.nc # Light sensor support component
+ArbitratedTempDeviceP.nc # Temperature sensor support component
+DemoSensorC.nc # Override TinyOS's default sensor
+PhotoC.nc # Light sensor HIL
+PhotoImplP.nc # Light sensor support component
+PhotoTempConfigC.nc # Shared support component
+PhotoTempConfigP.nc # Shared support component
+SharedAnalogDeviceC.nc # Shared support component
+SharedAnalogDeviceP.nc # Shared support component
+TempC.nc # Temperature Sensor HIL
+ca/TempImplP.nc # Temperature sensor support component
+ # (MDA100CA board)
+cb/TempImplP.nc # Temperature sensor support component
+ # (MDA100CB board)
+mda100.h # Header file for mda100
+</pre>
+<p>This sensor board provides only a HIL (PhotoC and TempC components), and overrides the
+TinyOS demo sensor (DemoSensorC). The demo sensor is an alias for PhotoC.</p>
+<p>The two forms of the mda100 differ only by the wiring of the
+temperature sensor. The user has to specify which form of the sensor
+board is in use by providing a <tt class="docutils literal"><span class="pre">-I%T/sensorboards/mda100/ca</span></tt> or
+<tt class="docutils literal"><span class="pre">-I%T/sensorboards/mda100/cb</span></tt> compiler option.</p>
+<p>This sensor board relies on a platform-provided <tt class="docutils literal"><span class="pre">MicaBusC</span></tt> component
+that specifies how the mica-family sensor board bus is connected to
+the microcontroller.</p>
+</div>
</div>
</div>
</body>
projects / tinyos-2.x.git / blobdiff