https://forge.codesys.com/forge/talk/Engineering/thread/f8017f4ba6/2023-07-19T09:31:09.869000ZRecent posts to ModbusRTU: SP12 -> SP162023-07-19T09:31:09.869000Z2023-07-19T09:31:09.869000Zlostcontrolhttps://forge.codesys.com/u/lostcontrol/https://forge.codesys.com7e7d7bd007773bf0773d1a9325c648e80a470ffa

<div class="markdown_content"><p>Nope, the attribute no_assign did not make a difference neither did the no_assign_warning.</p> <p>But, that change to reference declaration was the solution!!<br/> Thanks for taking the time to reply!</p></div>

2023-07-19T07:41:34.184000Z2023-07-19T07:41:34.184000ZTimvHhttps://forge.codesys.com/u/timvh/https://forge.codesys.com77be7c08d2597554dadefacf4fc805561b17c64c

<div class="markdown_content"><p>I'm not sure, but I guess it has the attribute 'no_assign'. Probably it is better to use a reference:</p> <div class="codehilite"><pre><span></span><span class="err">VAR_INPUT</span> <span class="err"> slave : REFERENCE TO IoDrvModbus.ModbusSlaveComPort;</span> <span class="err">END_VAR</span> </pre></div> </div>

2023-07-18T18:12:59.893000Z2023-07-18T18:12:59.893000Zlostcontrolhttps://forge.codesys.com/u/lostcontrol/https://forge.codesys.com8857a6700e2a09bb8097b382f9c532a2f4371b71

<div class="markdown_content"><p>Hi,<br/> I have had an application running on V3.5 SP12 that have since upgraded to V3.5 SP16 ( hardware supported version )</p> <p>I had a function block that had an input parameter:</p> <div class="codehilite"><pre><span></span><span class="n">slave</span> <span class="o">:</span> <span class="n">IoDrvModbus</span><span class="o">.</span><span class="na">ModbusSlaveComPort</span><span class="o">;</span> </pre></div> <p>This implementation worked as I expected.</p> <p>When I have upgraded to SP16/19, the same assignment does not compile &amp; gives error C0328 : Assignment not allowed for type ModbusSlaveComPort_Diag<br/> We are at a loss as to why this worked for SP12, but no longer for SP16. </p> <p>Ive managed a workaround for now which is not ideal.</p> <p>The reason for using this method vs the in-built scan list is to control the polling of the slaves and order.</p> <p>any takers?</p></div>