https://forge.codesys.com/forge/talk/CODESYS-V2/thread/5ad787a7d1/2020-02-27T21:13:17.432000ZRecent posts to Using the SysLibShm library2020-02-27T21:13:17.432000Z2020-02-27T21:13:17.432000Zcmbillohttps://forge.codesys.com/u/cmbillo/https://forge.codesys.com996e8a745844857353efec1e739a6bbcab7d1163

<div class="markdown_content"><p>Thanks TimvH!</p> <blockquote> <p><strong>TimvH hat geschrieben:</strong><br/> I have no experience with this and also no demo application, but the error is caused by not using a pointer.<br/> I think it should be something like:<br/> hMyShMem := SysShmOpen('MyShMem', 0, ADR(dwSize));</p> </blockquote></div>

2020-02-27T21:13:13.443000Z2020-02-27T21:13:13.443000Ztimvhhttps://forge.codesys.com/u/timvh/https://forge.codesys.come2f401bd42eef2fdd5cbd2ce2509a37cb671e877

<div class="markdown_content"><p>I have no experience with this and also no demo application, but the error is caused by not using a pointer.</p> <p>I think it should be something like:</p> <p>hMyShMem := SysShmOpen('MyShMem', 0, ADR(dwSize));</p></div>

2020-02-27T21:13:11.953000Z2020-02-27T21:13:11.953000Zcmbillohttps://forge.codesys.com/u/cmbillo/https://forge.codesys.com73d436ca1439833ae6acb66f4a2e6e4a98e61a4f

<div class="markdown_content"><p>Hello,</p> <p>I have downloaded the CoDeSys V2.3.8 Demo (with CoDeSys SP PLC WinNT V2.4 ).</p> <p>I´m testing the SysLibShm.lib (located in "C:\Program Files\Common Files\CAA-Targets\3S\Lib_PLCWinNT").</p> <p>My project compiles without errors, but when I try to run it, I get the following error:</p> <p>"#81: Access violation in 'Access violation Task = New Task'"</p> <p>The error occurs when I try to execute the following code:</p> <p>hMyShMem := SysShmOpen('MyShMem', 0, SIZEOF(aRxBuffer) + SIZEOF(aTxBuffer));</p> <p>My project source code is:</p> <p>Program Test</p> <p>VAR</p> <div class="codehilite"><pre><span></span><span class="n">hMyShMem</span><span class="o">:</span> <span class="n">DWORD</span> <span class="o">:=</span> <span class="mi">0</span><span class="o">;</span> <span class="n">aTxBuffer</span><span class="o">:</span> <span class="n">ARRAY</span><span class="o">[</span><span class="mi">0</span><span class="o">..</span><span class="mi">63</span><span class="o">]</span> <span class="n">OF</span> <span class="n">BYTE</span><span class="o">;</span> <span class="n">aRxBuffer</span><span class="o">:</span> <span class="n">ARRAY</span><span class="o">[</span><span class="mi">0</span><span class="o">..</span><span class="mi">63</span><span class="o">]</span> <span class="n">OF</span> <span class="n">BYTE</span><span class="o">;</span> <span class="n">dwRet</span><span class="o">:</span> <span class="n">DWORD</span><span class="o">;</span> <span class="n">dwTxErrorCounter</span><span class="o">:</span> <span class="n">DWORD</span> <span class="o">:=</span> <span class="mi">0</span><span class="o">;</span> <span class="n">dwRxErrorCounter</span><span class="o">:</span> <span class="n">DWORD</span> <span class="o">:=</span> <span class="mi">0</span><span class="o">;</span> </pre></div> <p>END_VAR</p> <p>IF (hMyShMem = 0) THEN</p> <div class="codehilite"><pre><span></span><span class="n">hMyShMem</span> <span class="p">:</span><span class="o">=</span> <span class="n">SysShmOpen</span><span class="p">(</span><span class="s1">'MyShMem'</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="n">SIZEOF</span><span class="p">(</span><span class="n">aRxBuffer</span><span class="p">)</span> <span class="o">+</span> <span class="n">SIZEOF</span><span class="p">(</span><span class="n">aTxBuffer</span><span class="p">));</span> <span class="o">&lt;</span><span class="c1">--------------- ERROR!!!!!</span> </pre></div> <p>ELSE</p> <div class="codehilite"><pre><span></span><span class="nv">dwRet</span> :<span class="o">=</span> <span class="nv">SysShmRead</span><span class="ss">(</span> <span class="nv">hMyShMem</span>, <span class="mi">0</span>, <span class="nv">ADR</span><span class="ss">(</span><span class="nv">aRxBuffer</span><span class="ss">)</span>, <span class="nv">SIZEOF</span><span class="ss">(</span><span class="nv">aRxBuffer</span><span class="ss">))</span><span class="c1">;</span> <span class="k">IF</span> <span class="ss">(</span><span class="nv">dwRet</span> <span class="o">=</span> <span class="nv">SIZEOF</span><span class="ss">(</span><span class="nv">aRxBuffer</span><span class="ss">))</span> <span class="k">THEN</span> <span class="c1">;</span> <span class="k">ELSE</span> <span class="nv">dwRxErrorCounter</span> :<span class="o">=</span> <span class="nv">dwRxErrorCounter</span> <span class="o">+</span> <span class="mi">1</span><span class="c1">;</span> <span class="nv">END_IF</span> <span class="nv">dwRet</span> :<span class="o">=</span> <span class="nv">SysShmWrite</span><span class="ss">(</span> <span class="nv">hMyShMem</span>, <span class="nv">SIZEOF</span><span class="ss">(</span><span class="nv">aRxBuffer</span><span class="ss">)</span>, <span class="nv">ADR</span><span class="ss">(</span><span class="nv">aTxBuffer</span><span class="ss">)</span>, <span class="nv">SIZEOF</span><span class="ss">(</span><span class="nv">aTxBuffer</span><span class="ss">))</span><span class="c1">;</span> <span class="k">IF</span> <span class="ss">(</span><span class="nv">dwRet</span> <span class="o">=</span> <span class="nv">SIZEOF</span><span class="ss">(</span><span class="nv">aTxBuffer</span><span class="ss">))</span> <span class="k">THEN</span> <span class="c1">;</span> <span class="k">ELSE</span> <span class="nv">dwTxErrorCounter</span> :<span class="o">=</span> <span class="nv">dwTxErrorCounter</span> <span class="o">+</span> <span class="mi">1</span><span class="c1">;</span> <span class="nv">END_IF</span> </pre></div> <p>END_IF</p> <p>Any idea why this error is occurring?</p> <p>What means this error message? </p> <p>Did anyone already use this library? Any example?</p> <p>Thanks a lot!</p> <p>Billo</p></div>