✎ Adding Support for a New LINX Remote I/O Device [LabVIEW MakerHub]

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.

<h1>Adding Support for a New LINX Remote I/O Device</h1>
<div class="level1">

<p>
This document contains a quick brain dump on adding support for a new LINX device.  This page should be cleaned up and split into separate pages as appropriate.
</p>

</div>

<h4>Firmware</h4>
<div class="level4">
<hr />
<ul>
<li class="level1"> Create the new device class in <pre class="code">\vi.lib\MakerHub\LINX\Firmware\Source\core\device

</pre><p> </p>
</li>
</ul>



<ul>
<li class="level1"> For wiring compatible devices it is easiest to copy an existing device's .cpp and .h file.</li>
<li class="level2"> Name the files Linx&lt;DeviceName&gt;.h and Linx&lt;DeviceName&gt;.cpp</li>
</ul>

</div>

<h5>Modify the .h file</h5>
<div class="level5">
<ul>
<li class="level1"> Update the comment section at the top</li>
<li class="level2"> Update the include gaurds to <b>LINX_&lt;DEVICENAME&gt;_H</b></li>
<li class="level2 node"> Update all of the defines:<ul>
<li class="level3"> Update the <b>DEVICE_NAME_LEN</b> to hold your device name.  This should be one more than the number of characters in the device name to hold the string null termination character.</li>
<li class="level3"> Update <b>NUM_AI_CHANS</b> with the number of AI channels on the device.</li>
<li class="level3"> Update <b>AI_RES_BITS</b> with the bits of resolution of the ADC.</li>
<li class="level3"> Update <b>AI_REFV</b> with the default AI reference voltage in micro volts.</li>
<li class="level3"> Update <b>NUM_AI_INT_REFS</b> with the number of configurable internal AI reference voltages.</li>
<li class="level3"> Update <b>NUM_DIGITAL_CHANS</b> with the number of DIO channels on the device.</li>
<li class="level3"> Update <b>NUM_PWM_CHANS</b> with the number of PWM channels on the device.</li>
<li class="level3"> Update <b>NUM_SPI_CHANS</b> with the number of SPI channels on the device.</li>
<li class="level3"> Update <b>NUM_SPI_SPEEDS</b> with the number of supported SPI clock rates.</li>
<li class="level3"> Update <b>NUM_I2C_CHANS</b> with the number of I2C channels on the device.</li>
<li class="level3"> Update <b>NUM_UART_CHANS</b> with the number of UART channels on the device.</li>
<li class="level3"> Update <b>NUM_UART_SPEEDS</b> with the number of supported UART baud rates.</li>
</ul>
</li>
<li class="level2"> Update the class name to &lt;DeviceName&gt;</li>
<li class="level2"> Update the constructor and destructor to match the new class name.</li>
</ul>

</div>

<h5>Modify the .cpp file</h5>
<div class="level5">
<ul>
<li class="level1"> Update the comment section at the top</li>
<li class="level1"> Update the <b>Linx<em><</em>DeviceName>.h</b> include to the new device name (this is the .h file created above)</li>
<li class="level1"> Change all of the class namespaces to the new device name (find and replace '<em><</em>OldDeviceName>::' with '<em><</em>NewDeviceName>::')</li>
<li class="level1"> Set the string value of <b>m_DeviceName</b> to your new device name.  This string must contain one fewer characters than <b>DEVICE_NAME_LEN</b>.</li>
<li class="level1"> Update <b>m_AiChans</b> with the devices AI channel / pin numbers.</li>
<li class="level1"> Update <b>m_AiRefIntVals</b> with the AI internal reference voltages in micro volts.</li>
<li class="level1"> Update <b>m_AiRefCodes</b> with the value required to set the corresponding AI refernce value see <a href="http://arduino.cc/en/Reference/analogReference" class="urlextern" title="http://arduino.cc/en/Reference/analogReference"  rel="nofollow"> analogReference()</a> for wiring devices).  The order of the AiRefCodes must match the order of the AiRefIntVals.</li>
<li class="level1"> Update <b>m_DigitalChans</b> with the devices DIO channel / pin numbers.</li>
<li class="level1"> Update <b>m_PwmChans</b> with the devices PWM channel / pin numbers.</li>
<li class="level1"> Update <b>m_SpiChans</b> with the device SPI channel numbers.  These are typically arbitrary numbers starting at 0.  Wiring devices typically only support 1 SPI channel.  Other device families need to handle these values accordingly in their family level class.</li>
<li class="level1"> Update <b>m_SpiSupportedSpeeds</b> with the supoprted SPI clock rates.</li>
<li class="level1"> Update <b>m_SpiSpeedCodes</b> with the values to set the above SPI clock rates.  For wiring devices see <a href="http://arduino.cc/en/Reference/SPISetClockDivider" class="urlextern" title="http://arduino.cc/en/Reference/SPISetClockDivider"  rel="nofollow"> setClockDivider()</a></li>
<li class="level1"> Update <b>m_I2cChans</b> with the device I2c channel numbers.  These are typically arbitrary numbers starting at 0.  Wiring devices typically only support 1 I2c channel.  Other device families need to handle these values accordingly in their family level class.</li>
<li class="level1"> <b>m_I2cRefCount</b> is used to determine if the I2C channel is open typically does not need to be altered here.</li>
<li class="level1"> Update <b>m_UartChans</b> with the UART channel / pin numbers for the device.  These are typically arbitrary numbers starting at 0.  Up to 4 UARTs are supported for LINX wiring devices at the time of writing and more can be added by updated the WiringDevice class.</li>
<li class="level1"> Update <b>m_UartSupportedSpeeds</b> with the UART buad rate values.  These values are directly used with the <a href="http://arduino.cc/en/Serial/begin" class="urlextern" title="http://arduino.cc/en/Serial/begin"  rel="nofollow"> Serial.begin()</a> function for wiring devices.</li>
<li class="level1"> Update <b>m_Servos</b> with enough '0' (zeros) to match NUM_DIGITAL_CHANS.  These are null pointers that will be populated when the user initializes a servo.</li>
</ul>
<ul>
<li class="level1"> Update the constructor name to &lt;DeviceName&gt;::&lt;DeviceName&gt;()</li>
<li class="level1"> Update the <b>DeviceFamily</b> and <b>DeviceID</b>.  See <a href="/doku.php?id=learn:libraries:linx:supported_devices" class="wikilink2" title="learn:libraries:linx:supported_devices" rel="nofollow">supported_devices</a> for more info and post on the forum if the device in question is not on that list.</li>
<li class="level1"> Set the LINX API versions.  This indicates which features are supported and helps alert the user if their firmware is out of date after updating the host side code.</li>
<li class="level1"> If the device supports external AI reference values set <b>AiRefExtMin</b> to the minimum voltage in micro volts and <b>AiRefExtMax</b> to the maximum voltage in micro volts.</li>
<li class="level1"> Update the destructor name to &lt;DeviceName&gt;::~&lt;DeviceName&gt;()  (don't forget the <b>'~'</b>).</li>
</ul>

</div>

<h5>Config.h</h5>
<div class="level5">

<p>
Create a new device config file in 
</p>
<pre class="code">\vi.lib\MakerHub\LINX\Firmware\Source\core\device\config

</pre><p> </p>

<p>
<span class='np_break'> </span>
and name it Linx<em><</em>DeviceName>.h.   This file will be scripted into the libraries folder and is used to work around some limitations of the Arduino style build processes.
</p>
<ul>
<li class="level1"> Update the comment section at the top</li>
<li class="level1"> <b>Do not</b> change the <b>LINXCONFIG</b> include guard</li>
<li class="level1"> Define the number of channels on the device</li>
<li class="level1"> Set the device family code</li>
<li class="level1"> Set the <b>ARDUINO_VERSION</b> to match the IDE version used to build the firmware.  This is used to deal with some API changes in the different wiring versions.</li>
</ul>

</div>

<h5>Example Firmware</h5>
<div class="level5">

<p>
Add a firmware example to 
</p>
<pre class="code">\vi.lib\MakerHub\LINX\Firmware\Source\core\examples\&lt;DeviceFamily&gt;_&lt;DeviceName&gt;_&lt;Interface&gt;\&lt;DeviceFamily&gt;_&lt;DeviceName&gt;_&lt;Interface&gt;

</pre><p> </p>

<p>
<span class='np_break'> </span>
.  For wiring compatible devices it is easiest to copy and update an existing example:
</p>
<ul>
<li class="level1"> Update the comment section at the top</li>
<li class="level1"> Update the device specific include to include the new device <b>#include < <em><</em>DeviceName>.h></b></li>
<li class="level1"> Update the LinxDevice pointer type to match the new device type: <b><em><</em>DeviceName>* LinxDevice;</b></li>
<li class="level1"> Update the setup function to instantiate the new device type: <b>LinxDevice = new <em><</em>DeviceName>();</b></li>
</ul>

</div>

<h5>Libraries</h5>
<div class="level5">

<p>
In order to support the Arduino style IDEs and build processes the the <b>Generate Firmware Libraries</b> wizard is used to reorganize and rename files to fit the target build environment.  In order to script the new firmware a new entry needs to be added to 
</p>
<pre class="code">\vi.lib\MakerHub\LINX\Firmware\Source\libraries.ini

</pre><p> </p>




<p>
 <br/>
<br/>

Replace all instances of <b><em><</em>DeviceName></b> below with the new device name:
</p>
<pre class="code">;---------------------------------- &lt;DeviceName&gt; ----------------------------------

[&lt;DeviceName&gt;] 
;Device Specific Class
core/device/Linx&lt;DeviceName&gt;.h = Linx&lt;DeviceName&gt;/Linx&lt;DeviceName&gt;.h
core/device/Linx&lt;DeviceName&gt;.cpp = Linx&lt;DeviceName&gt;/Linx&lt;DeviceName&gt;.cpp
;Device Specific Config
core/device/config/Linx&lt;DeviceName&gt;.h = Linx&lt;DeviceName&gt;/config/LinxConfig.h
;Arduino Common
core/device/utility/LinxDevice.h = Linx&lt;DeviceName&gt;/utility/LinxDevice.h
core/device/utility/LinxDevice.cpp = Linx&lt;DeviceName&gt;/utility/LinxDevice.cpp
core/device/utility/LinxWiringDevice.h = Linx&lt;DeviceName&gt;/utility/LinxWiringDevice.h
core/device/utility/LinxWiringDevice.cpp = Linx&lt;DeviceName&gt;/utility/LinxWiringDevice.cpp

</pre><p> </p>




<p>
 <br/>

</p>

</div>

<h5>Building the Firmware</h5>
<div class="level5">
<ul>
<li class="level1"> Use the <b>Generate Firmware Libraries</b> wizard in LabVIEW to generate new firmware libraries from the source directory in the <b>libraries</b> directory for the device IDE.</li>
<li class="level1"> Restart the device IDE</li>
<li class="level1"> Open the scripted version of the example firmware created above.  For wiring devices the example should be available inside the IDE in File>>Examples>>LINX>><em><</em>ExampleName>.</li>
<li class="level1"> Build and deploy the example</li>
<li class="level1"> Run a simple LINX Example in LabVIEW to see if the firmware is working.</li>
</ul>

</div>
This site was deprecated on August 1, 2020

Page Tools
