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How to use Atmel TSADCC Sysfs Interface - Revision history
2024-03-28T10:52:15Z
Revision history for this page on the wiki
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https://wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2921&oldid=prev
Kyoungmeyer at 20:56, 2 January 2014
2014-01-02T20:56:57Z
<p></p>
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 20:56, 2 January 2014</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td></tr>
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Kyoungmeyer
https://wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2919&oldid=prev
Kyoungmeyer at 20:55, 2 January 2014
2014-01-02T20:55:38Z
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 20:55, 2 January 2014</td>
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<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>{{todo|<del class="diffchange diffchange-inline">FinalDraft</del>;(12.16.13-12:00->MG+);(01.02.14-12:35->KY+);(01.02.14-14:00->MD-);(01.02.14-14:40->MG+)|Michael Gloff|project=oe 4,oe 5,md,mg,ky,<del class="diffchange diffchange-inline">FinalDraft</del>}}</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>{{todo|<ins class="diffchange diffchange-inline">Completet</ins>;(12.16.13-12:00->MG+);(01.02.14-12:35->KY+);(01.02.14-14:00->MD-);(01.02.14-14:40->MG<ins class="diffchange diffchange-inline">+);(01.02.14-14:55->KY</ins>+)|Michael Gloff|project=oe 4,oe 5,md,mg,ky,<ins class="diffchange diffchange-inline">complete</ins>}}</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td></tr>
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Kyoungmeyer
https://wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2917&oldid=prev
Mgloff at 20:43, 2 January 2014
2014-01-02T20:43:51Z
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 20:43, 2 January 2014</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l1" >Line 1:</td>
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<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>{{todo|<del class="diffchange diffchange-inline">Review</del>;(12.16.13-12:00->MG+);(01.02.14-12:35->KY+);(01.02.14-14:00->MD-)|Michael Gloff|project=oe 4,oe 5,<del class="diffchange diffchange-inline">Review</del>,<del class="diffchange diffchange-inline">md</del>,ky}}</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>{{todo|<ins class="diffchange diffchange-inline">FinalDraft</ins>;(12.16.13-12:00->MG+);(01.02.14-12:35->KY+);(01.02.14-14:00->MD-<ins class="diffchange diffchange-inline">);(01.02.14-14:40->MG+</ins>)|Michael Gloff|project=oe 4,oe 5,<ins class="diffchange diffchange-inline">md</ins>,<ins class="diffchange diffchange-inline">mg</ins>,ky<ins class="diffchange diffchange-inline">,FinalDraft</ins>}}</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>INDEX_VALUE=0xffef <br /></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>INDEX_VALUE=0xffef <br /></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0xf<br /></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0xf<br /></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>A minimal sample and hold time are necessary for the touchscreen controller to  provide the best converted value between two channels. This can be set to a value in the range of <del class="diffchange diffchange-inline">from </del>1 through 16 clock cycles. The default value provided by EMAC is typically 16 clock cyles which we have found to provide the best accuracy during testing; however, it may be that altering this value to be lower may produce a more responsive interface.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>A minimal sample and hold time are necessary for the touchscreen controller to  provide the best converted value between two channels. This can be set to a value in the range of 1 through 16 clock cycles. The default value provided by EMAC is typically 16 clock cyles which we have found to provide the best accuracy during testing; however, it may be that altering this value to be lower may produce a more responsive interface.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===Pen Debounce Time===</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===Pen Debounce Time===</div></td></tr>
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Mgloff
https://wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2911&oldid=prev
Mdean: Made many changes; downgraded to Review status.
2014-01-02T20:02:14Z
<p>Made many changes; downgraded to Review status.</p>
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 20:02, 2 January 2014</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l1" >Line 1:</td>
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<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>{{todo|<del class="diffchange diffchange-inline">Final Draft</del>;(12.16.13-12:00->MG+);(01.02.14-12:35->KY+)|Michael Gloff|project=oe 4,oe 5,<del class="diffchange diffchange-inline">finaldraft</del>,md,ky}}</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>{{todo|<ins class="diffchange diffchange-inline">Review</ins>;(12.16.13-12:00->MG+);(01.02.14-12:35->KY+<ins class="diffchange diffchange-inline">);(01.02.14-14:00->MD-</ins>)|Michael Gloff|project=oe 4,oe 5,<ins class="diffchange diffchange-inline">Review</ins>,md,ky}}</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>  /sys/class/gpio/indexed_tsopt/data</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>  /sys/class/gpio/indexed_tsopt/data</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The <del class="diffchange diffchange-inline">'''</del>/sys/class/gpio/indexed_tsopt/index<del class="diffchange diffchange-inline">''' </del>controls which aspect of the touchscreen</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The <ins class="diffchange diffchange-inline"><code></ins>/sys/class/gpio/indexed_tsopt/index<ins class="diffchange diffchange-inline"></code> virtual file </ins>controls which aspect of the touchscreen</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>driver is to be modified and <del class="diffchange diffchange-inline">'''</del>/sys/class/gpio/indexed_tsopt/data<del class="diffchange diffchange-inline">''' </del>controls the</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>driver is to be modified and <ins class="diffchange diffchange-inline"><code></ins>/sys/class/gpio/indexed_tsopt/data<ins class="diffchange diffchange-inline"></code> </ins>controls the</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>value to be modified.  </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>value to be modified.  </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>There are <del class="diffchange diffchange-inline">also </del>two <del class="diffchange diffchange-inline">basic </del>command forms that are recommended for modifying</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>There are two <ins class="diffchange diffchange-inline">common </ins>command forms that are recommended for modifying <ins class="diffchange diffchange-inline">the values exported by the virtual files </ins></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">'''</del>/sys/class/gpio/indexed_tsopt/index<del class="diffchange diffchange-inline">''' </del>and <del class="diffchange diffchange-inline">'''</del>/sys/class/gpio/indexed_tsopt/data<del class="diffchange diffchange-inline">'''</del>.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"><code></ins>/sys/class/gpio/indexed_tsopt/index<ins class="diffchange diffchange-inline"></code> </ins>and <ins class="diffchange diffchange-inline"><code></ins>/sys/class/gpio/indexed_tsopt/data<ins class="diffchange diffchange-inline"></code></ins>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Those are:</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Those are:</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l24" >Line 24:</td>
<td colspan="2" class="diff-lineno">Line 24:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>  $ cat /sys/class/gpio/indexed_tsopt/data</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>  $ cat /sys/class/gpio/indexed_tsopt/data</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The <del class="diffchange diffchange-inline">'</del>echo<del class="diffchange diffchange-inline">' </del>command form allows one to modify the current value of the file whereas the <del class="diffchange diffchange-inline">'</del>cat<del class="diffchange diffchange-inline">' </del>command form allows one to view the current value of the file. A common workflow may be to <del class="diffchange diffchange-inline">'</del>echo<del class="diffchange diffchange-inline">' </del>an INDEX_VALUE into <del class="diffchange diffchange-inline">'''</del>/sys/class/gpio/indexed_tsopt/index<del class="diffchange diffchange-inline">''' </del>then <del class="diffchange diffchange-inline">'</del>cat<del class="diffchange diffchange-inline">' </del>the <del class="diffchange diffchange-inline">'''</del>/sys/class/gpio/indexed_tsopt/data<del class="diffchange diffchange-inline">''' </del>to view on the command line.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The <ins class="diffchange diffchange-inline"><code></ins>echo<ins class="diffchange diffchange-inline"></code> </ins>command form allows one to modify the current value of the file whereas the <ins class="diffchange diffchange-inline"><code></ins>cat<ins class="diffchange diffchange-inline"></code> </ins>command form allows one to view the current value of the file. A common workflow may be to <ins class="diffchange diffchange-inline"><code></ins>echo<ins class="diffchange diffchange-inline"></code> </ins>an INDEX_VALUE into <ins class="diffchange diffchange-inline"><code></ins>/sys/class/gpio/indexed_tsopt/index<ins class="diffchange diffchange-inline"></code> </ins>then <ins class="diffchange diffchange-inline"><code></ins>cat<ins class="diffchange diffchange-inline"></code> </ins>the <ins class="diffchange diffchange-inline"><code></ins>/sys/class/gpio/indexed_tsopt/data<ins class="diffchange diffchange-inline"></code> </ins>to view <ins class="diffchange diffchange-inline">its set value </ins>on the command line<ins class="diffchange diffchange-inline">.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Although the above two methods are the most commonly used command line methods for interacting with these virtual files, other methods will work as well.  For instance, <code>printf</code> can be used to write values:</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> $ printf $INDEX_VALUE > /sys/class/gpio/indexed_tsopt/index</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Similarly, the value can be read with the <code>more</code> command:</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> $ more /sys/class/gpio/indexed_tsopt/index</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Any method of writing ASCII text or reading ASCII text can be used to interact with these virtual files.  In a C program, <code>fopen</code> can be used with <code>fprintf</code> to write to one of these files</ins>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The following touch screen parameters may be modified through the use of the</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The following touch screen parameters may be modified through the use of the</div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l34" >Line 34:</td>
<td colspan="2" class="diff-lineno">Line 44:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>INDEX_VALUE=0xffef <br /></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>INDEX_VALUE=0xffef <br /></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0xf<br /></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0xf<br /></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>A minimal sample and hold time are necessary for the touchscreen controller to  provide the best converted value between two channels. This can be set to <del class="diffchange diffchange-inline">between </del>1 <del class="diffchange diffchange-inline">and </del>16 clock cycles. The default value provided by EMAC is typically 16 clock cyles which we have found to provide the best accuracy during testing; however, it may be that altering this value to be lower may produce a more responsive interface.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>A minimal sample and hold time are necessary for the touchscreen controller to  provide the best converted value between two channels. This can be set to <ins class="diffchange diffchange-inline">a value in the range of from </ins>1 <ins class="diffchange diffchange-inline">through </ins>16 clock cycles. The default value provided by EMAC is typically 16 clock cyles which we have found to provide the best accuracy during testing; however, it may be that altering this value to be lower may produce a more responsive interface.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===Pen Debounce Time===</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===Pen Debounce Time===</div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l40" >Line 40:</td>
<td colspan="2" class="diff-lineno">Line 50:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0xf<br /></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0xf<br /></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The Atmel TSADCC driver for Linux uses the touchscreen controller's Pen Detect Method to begin triggering conversions. In order for this to happen, a</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The Atmel TSADCC driver for Linux uses the touchscreen controller's Pen Detect Method to begin triggering conversions. In order for this to happen, a</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>programmable debouncer determines how <del class="diffchange diffchange-inline">long current </del>must <del class="diffchange diffchange-inline">flow </del>before an interrupt is generated to indicate that conversions should start taking place</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>programmable debouncer determines how <ins class="diffchange diffchange-inline">many sequential clock periods with a touch detected </ins>must <ins class="diffchange diffchange-inline">occur </ins>before an interrupt is generated to indicate that conversions should start taking place in the controller. The debouncer is programmable from 1 ADC clock period to 2^15 ADC clock periods depending on the value of PENDBC.</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>in the controller. The debouncer is programmable from 1 ADC clock period to 2^15 ADC clock periods depending on the value of PENDBC.</div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===Touchscreen ADC Prescalar===</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===Touchscreen ADC Prescalar===</div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l50" >Line 50:</td>
<td colspan="2" class="diff-lineno">Line 59:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>frequency uses this value:</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>frequency uses this value:</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>  ADCCLK = MASTERCLK/((PRESCALAR +1)*2).  </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>  ADCCLK = MASTERCLK/((PRESCALAR + 1)*2).  </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The default value provided by EMAC varies greatly between different touchscreens as a part of the optimization process for each product.  </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The default value provided by EMAC varies greatly between different touchscreens as a part of the optimization process for each product.  </div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l57" >Line 57:</td>
<td colspan="2" class="diff-lineno">Line 66:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>INDEX_VALUE=0xfff8<br /></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>INDEX_VALUE=0xfff8<br /></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0x279 for 12-inch display<br /></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0x279 for 12-inch display<br /></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The X-Panel Resistance measurement is a constant coefficient in the equation <del class="diffchange diffchange-inline">that </del>determines the touch pressure from the values measured by the touchscreen controller <del class="diffchange diffchange-inline">which </del>varies from touchscreen to touchscreen and should be kept in mind when modifying the Touchscreen Pressure Sensitivity since the two are closely related.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The X-Panel Resistance measurement is a constant coefficient in the equation <ins class="diffchange diffchange-inline">which </ins>determines the touch pressure from the values measured by the touchscreen controller<ins class="diffchange diffchange-inline">.  This value </ins>varies from touchscreen to touchscreen and should be kept in mind when modifying the Touchscreen Pressure Sensitivity since the two are closely related.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===Touchscreen Pressure Sensitivity===</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===Touchscreen Pressure Sensitivity===</div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l68" >Line 68:</td>
<td colspan="2" class="diff-lineno">Line 77:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The effect of increasing this value is to make the touchscreen more sensitive to light touches. The effect of decreasing this value is to make the</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The effect of increasing this value is to make the touchscreen more sensitive to light touches. The effect of decreasing this value is to make the</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>touchscreen require harder touches to actually register as a touch in the first place. Requiring a greater touch pressure will help when light touches produce ambiguous readings which manifest as inaccurate and sometimes spurious values sent to userspace from the driver. The downside <del class="diffchange diffchange-inline">of course </del>is that harder, more intentional presses are needed to register the touch.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>touchscreen require harder touches to actually register as a touch in the first place. Requiring a greater touch pressure will help when light touches produce ambiguous readings which manifest as inaccurate and sometimes spurious values sent to userspace from the driver. The downside is that harder, more intentional presses are needed to register the touch.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Note that there is a linear relationship between the Touchscreen Pressure Sensitivity and the Touchscreen X-Panel Resistance.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Note that there is a linear relationship between the Touchscreen Pressure Sensitivity and the Touchscreen X-Panel Resistance.</div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l75" >Line 75:</td>
<td colspan="2" class="diff-lineno">Line 84:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>INDEX_VALUE=0xffff<br /></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>INDEX_VALUE=0xffff<br /></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0x14<br /></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>DATA_VALUE recommended default: 0x14<br /></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>This value determines how many measurement samples are used by the touch screen driver to provide an average value that gets reported to the Linux input subsystem which is then available for userspace applications to accept as input. By default, EMAC has set a maximum of 30 filter samples so if the DATA_VALUE passed to <del class="diffchange diffchange-inline">'''</del>/sys/class/gpio/indexed_tsopt/data<del class="diffchange diffchange-inline">''' </del>is greater than 0x1e, the value will simply be 30. This can be changed by editing the</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>This value determines how many measurement samples are used by the touch screen driver to provide an average value that gets reported to the Linux input subsystem which is then available for userspace applications to accept as input. By default, EMAC has set a maximum of 30 filter samples so if the DATA_VALUE passed to <ins class="diffchange diffchange-inline"><code></ins>/sys/class/gpio/indexed_tsopt/data<ins class="diffchange diffchange-inline"></code> </ins>is greater than 0x1e, the value will simply be 30. This can be changed by editing the</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">"</del>atmel_tsadcc.c<del class="diffchange diffchange-inline">" </del>file line that says <del class="diffchange diffchange-inline">"</del>#define COUNT_MAX 30<del class="diffchange diffchange-inline">"</del>.  </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"><code></ins>atmel_tsadcc.c<ins class="diffchange diffchange-inline"></code> </ins>file line that says <ins class="diffchange diffchange-inline"><code></ins>#define COUNT_MAX 30<ins class="diffchange diffchange-inline"></code>.  Larger values will provide improved noise rejection at the expense of causing the input to lag</ins>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===A Note Regarding TSLIB===</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===A Note Regarding TSLIB===</div></td></tr>
</table>
Mdean
https://wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2870&oldid=prev
Kyoungmeyer at 18:35, 2 January 2014
2014-01-02T18:35:37Z
<p></p>
<table class="diff diff-contentalign-left" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 18:35, 2 January 2014</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l1" >Line 1:</td>
<td colspan="2" class="diff-lineno">Line 1:</td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>{{todo|<del class="diffchange diffchange-inline">Review</del>;(12.16.13-12:00->MG+);|Michael Gloff|project=oe 4,oe 5,md,ky}}</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>{{todo|<ins class="diffchange diffchange-inline">Final Draft</ins>;(12.16.13-12:00->MG+);<ins class="diffchange diffchange-inline">(01.02.14-12:35->KY+)</ins>|Michael Gloff|project=oe 4,oe 5<ins class="diffchange diffchange-inline">,finaldraft</ins>,md,ky}}</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
</table>
Kyoungmeyer
https://wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2756&oldid=prev
Mgloff at 17:47, 31 December 2013
2013-12-31T17:47:45Z
<p></p>
<table class="diff diff-contentalign-left" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 17:47, 31 December 2013</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l1" >Line 1:</td>
<td colspan="2" class="diff-lineno">Line 1:</td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">{{todo|Review;(12.16.13-12:00->MG+);|Michael Gloff|project=oe 4,oe 5,md,ky}}</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==How to Use the Atmel TSADCC Sysfs Interface==</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
</table>
Mgloff
https://wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2571&oldid=prev
Mgloff at 17:15, 27 December 2013
2013-12-27T17:15:28Z
<p></p>
<table class="diff diff-contentalign-left" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 17:15, 27 December 2013</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l80" >Line 80:</td>
<td colspan="2" class="diff-lineno">Line 80:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>EMAC OpenEmbedded filesystems ship with a utility known as tslib which includes a number of userspace touchscreen drivers and modules that are intended to improve the performance of the touchscreen. Settings for this file can be found in /etc/ts.conf. In it, there are four lines:</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>EMAC OpenEmbedded filesystems ship with a utility known as tslib which includes a number of userspace touchscreen drivers and modules that are intended to improve the performance of the touchscreen. Settings for this file can be found in /etc/ts.conf. In it, there are four lines:</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">:</del>module pthres pmin=1</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> </ins>module pthres pmin=1</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">:</del>module variance delta=30</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> </ins>module variance delta=30</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">:</del>module dejiter delta=100</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> </ins>module dejiter delta=100</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">:</del>module linear</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> </ins>module linear</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>If you are experiencing a touchscreen problem in which the mouse cursor jitters around the screen and "pre-clicks" a point other than where you intended, it may be necessary to change the settings in this file. While testing at EMAC, we have found that disabling the "variance" module will prevent the pre-clicks, although this will not prevent the mouse from jittering across the screen. To disable this module, either delete the line or comment it out with a hash symbol:</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>If you are experiencing a touchscreen problem in which the mouse cursor jitters around the screen and "pre-clicks" a point other than where you intended, it may be necessary to change the settings in this file. While testing at EMAC, we have found that disabling the "variance" module will prevent the pre-clicks, although this will not prevent the mouse from jittering across the screen. To disable this module, either delete the line or comment it out with a hash symbol:</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>  #module variance delta=30</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>  #module variance delta=30</div></td></tr>
</table>
Mgloff
https://wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2568&oldid=prev
Mgloff at 17:13, 27 December 2013
2013-12-27T17:13:18Z
<p></p>
<a href="//wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2568&oldid=2567">Show changes</a>
Mgloff
https://wiki.emacinc.com/index.php?title=How_to_use_Atmel_TSADCC_Sysfs_Interface&diff=2567&oldid=prev
Mgloff: Created page with "==How to Use the Atmel TSADCC Sysfs Interface == This guide will demonstrate how to use the sysfs interface for the Atmel touchscreen driver. There are two basic files used ..."
2013-12-27T16:52:18Z
<p>Created page with "==How to Use the Atmel TSADCC Sysfs Interface == This guide will demonstrate how to use the sysfs interface for the Atmel touchscreen driver. There are two basic files used ..."</p>
<p><b>New page</b></p><div>==How to Use the Atmel TSADCC Sysfs Interface<br />
==<br />
<br />
This guide will demonstrate how to use the sysfs interface for the Atmel<br />
touchscreen driver.<br />
<br />
There are two basic files used to interface with the touchscreen driver:<br />
/sys/class/gpio/indexed_tsopt/index<br />
/sys/class/gpio/indexed_tsopt/data<br />
<br />
The /sys/class/gpio/indexed_tsopt/index controls which aspect of the touchscreen<br />
driver is to be modified and /sys/class/gpio/indexed_tsopt/data controls the<br />
value to be modified. <br />
<br />
There are also two basic command forms that are recommended for modifying<br />
/sys/class/gpio/indexed_tsopt/index and /sys/class/gpio/indexed_tsopt/data.<br />
Those are:<br />
<br />
$ echo INDEX_VALUE > /sys/class/gpio/indexed_tsopt/index<br />
$ echo DATA_VALUE > /sys/class/gpio/indexed_tsopt/data<br />
<br />
and<br />
<br />
$ cat /sys/class/gpio/indexed_tsopt/index<br />
$ cat /sys/class/gpio/indexed_tsopt/data<br />
<br />
The 'echo' command form allows one to modify the current value of the file<br />
whereas the 'cat' command form allows one to view the current value of the file.<br />
A common workflow may be to 'echo' an INDEX_VALUE into<br />
/sys/class/gpio/indexed_tsopt/index then 'cat' the<br />
/sys/class/gpio/indexed_tsopt/data to view on the command line.<br />
<br />
The following touch screen parameters may be modified through the use of the<br />
above commands:<br />
<br />
Touchscreen Mode<br />
Sample and Hold Time<br />
INDEX_VALUE=0xffef<br />
DATA_VALUE recommended default: 0xf<br />
A minimal sample and hold time are necessary for the touchscreen controller to<br />
provide the best converted value between two channels. This can be set to<br />
between 1 and 16 clock cycles. The default value provided by EMAC is typically<br />
16 clock cyles which we have found to provide the best accuracy during<br />
testing; however, it may be that altering this value to be lower may produce a<br />
more responsive interface.<br />
<br />
Pen Debounce Time<br />
INDEX_VALUE=0xfff0<br />
DATA_VALUE recommended default: 0xf<br />
The Atmel TSADCC driver for Linux uses the touchscreen controller's Pen Detect<br />
Method to begin triggering conversions. In order for this to happen, a<br />
programmable debouncer determines how long current must flow before an<br />
interrupt is generated to indicate that conversions should start taking place<br />
in the controller. The debouncer is programmable from 1 ADC clock period to<br />
2^15 ADC clock periods depending on the value of PENDBC.<br />
<br />
Touchscreen ADC Prescalar<br />
INDEX_VALUE=0xfff4<br />
DATA_VALUE recommended default: 0x6e<br />
This value controls the ADC clock used to convert the touchscreen analog<br />
readings to digital values inside the Atmel TSADCC Controller. Acceptable<br />
values for the DATA_VALUE range from 0x00 to 0xff. The SoM-9g45 Master Clock<br />
has a frequency of 133.3 MHz. The formula used to determine the ADC clock<br />
frequence uses this value:<br />
<br />
ADCCLK = MASTERCLK/((PRESCALAR +1)*2). <br />
<br />
The default value provided by EMAC varies greatly between different<br />
touchscreens as a part of the optimization process for each product. <br />
<br />
Touchscreen X-Panel Resistance<br />
INDEX_VALUE=0xfff8<br />
DATA_VALUE recommended default: 0x279 for 12-inch display<br />
The X-Panel Resistance measurement is a constant coefficient in the equation<br />
that determines the touch pressure from the values measured by the touchscreen<br />
controller which varies from touchscreen to touchscreen and should be kept in mind<br />
when modifying the Touchscreen Pressure Sensitivity since the two are closely<br />
related.<br />
<br />
Touchscreen Pressure Sensitivity<br />
INDEX_VALUE=0xfffc<br />
DATA_VALUE recommended default: 0x200<br />
This value refers to the pressure filter in the Atmel driver that EMAC set up<br />
to provide a threshold over which no touchscreen measurements will be passed to<br />
the Linux input driver. <br />
<br />
To understand how this works, it is necessary to know that the harder one<br />
presses on the touch screen, the LOWER the value of the pressure reading. So<br />
the threshold set by using this INDEX_VALUE is the largest measurement value<br />
that the driver will accept as a true touch representing the weakest physical<br />
contact with the touchscreen panel.<br />
<br />
The effect of increasing this value is to make the touchscreen more sensitive<br />
to light touches. The effect of decreasing this value is to make the<br />
touchscreen require harder touches to actually register as a touch in the first<br />
place. Requiring a greater touch pressure will help when light touches produce<br />
ambiguous readings which manifest as inaccurate and sometimes spurious values<br />
sent to userspace from the driver. The downside of course is that harder, more<br />
intentional presses are needed to register the touch.<br />
<br />
Note that there is a linear relationship between the Touchscreen Pressure<br />
Sensitivity and the Touchscreen X-Panel Resistance.<br />
<br />
Touchscreen Filter<br />
INDEX_VALUE=0xffff<br />
DATA_VALUE recommended default: 0x14<br />
This value determines how many measurement samples are used by the touch screen<br />
driver to provide an average value that gets reported to the Linux input<br />
subsystem which is then available for userspace applications to accept as<br />
input. By default, EMAC has set a maximum of 30 filter samples so if the<br />
DATA_VALUE passed to /sys/class/gpio/indexed_tsopt/data is greater than 0x1e,<br />
the value will simply be 30. This can be changed by editing the<br />
"atmel_tsadcc.c" file line that says "#define COUNT_MAX 30".<br />
<br />
A Note Regarding TSLIB<br />
EMAC OpenEmbedded filesystems ship with a utility known as tslib which includes<br />
a number of userspace touchscreen drivers and modules that are intended to<br />
improve the performance of the touchscreen. Settings for this file can be found<br />
in /etc/ts.conf. In it, there are four lines:<br />
<br />
module pthres pmin=1<br />
module variance delta=30<br />
module dejiter delta=100<br />
module linear<br />
<br />
If you are experiencing a touchscreen problem in which the mouse cursor jitters<br />
around the screen and "pre-clicks" a point other than where you intended, it<br />
may be necessary to change the settings in this file. While testing at EMAC, we<br />
have found that disabling the "variance" module will prevent the pre-clicks,<br />
although this will not prevent the mouse from jittering across the screen. To<br />
disable this module, either delete the line or comment it out with a hash<br />
symbol:<br />
<br />
#module variance delta=30</div>
Mgloff