https://forge.codesys.com/forge/talk/Engineering/thread/2037f2ed1a/2021-07-06T13:26:13.290000ZRecent posts to Modbus configuration2021-07-06T13:26:13.290000Z2021-07-06T13:26:13.290000Zjoanmhttps://forge.codesys.com/u/joanm/https://forge.codesys.comca36d7b5ab97ef82c2652118b348327a1f18e722

<div class="markdown_content"><p>OK, solved... in TWinCAT you MUST put the variable you want to connect to any IO channel as %I<em> / %Q</em> or similar... it looks like in Codesys you MUST NOT.</p> <p>After reading the message slowly (good for me) I've been able to solve it and now I can directly assign the structure to the beginning of the Modbus channel.</p> <p>^^¡</p></div>

2021-06-30T11:34:06.639000Z2021-06-30T11:34:06.639000Zjoanmhttps://forge.codesys.com/u/joanm/https://forge.codesys.com9bb5e2cdc7d2b7497045efb75f6d786d5eadba46

<div class="markdown_content"><p>Hello all,</p> <p><strong>INTRODUCTION</strong><br/> Started using Codesys this week, been using TWinCAT for years though.</p> <p>Programming is not an issue given my background, but the configuration part changes a little and I have a doubt about the <em>ModbusTCPSlave I/O Mapping</em>.</p> <p>I've got some information from the manufacturer of the device I'm programming and the device will send me 1 BYTEs, 1 WORDs, 1 BYTEs and 15 REALs (64 bytes or 32 words in total).</p> <p>Those variables are inside a structure:</p> <div class="codehilite"><pre><span></span><span class="err">TYPE ST_MODBUS_DATA_FROM_DEVICE_1 :</span> <span class="err">STRUCT</span> <span class="err"> B01 : BYTE := 0;</span> <span class="err"> w01 : WORD := 0;</span> <span class="err"> B02 : BYTE := 0;</span> <span class="err"> r01 : REAL := 0.0;</span> <span class="err"> r02 : REAL := 0.0;</span> <span class="err"> r03 : REAL := 0.0;</span> <span class="err"> r04 : REAL := 0.0;</span> <span class="err"> r05 : REAL := 0.0;</span> <span class="err"> r06 : REAL := 0.0;</span> <span class="err"> r07 : REAL := 0.0;</span> <span class="err"> r08 : REAL := 0.0;</span> <span class="err"> r09 : REAL := 0.0;</span> <span class="err"> r10 : REAL := 0.0;</span> <span class="err"> r11 : REAL := 0.0;</span> <span class="err"> r12 : REAL := 0.0;</span> <span class="err"> r13 : REAL := 0.0;</span> <span class="err"> r14 : REAL := 0.0;</span> <span class="err"> r15 : REAL := 0.0;</span> <span class="err">END_STRUCT</span> <span class="err">END_TYPE</span> </pre></div> <p>I've added 1 channel, with an offset of 16#7531 and a length of 32.</p> <p>This has created an array<span>[0..31]</span> of WORD in the ModbusTCPSlave I/O Mapping.</p> <p>Now, I want to link/map the variables into the channel, but I have BYTEs and REALs not WORDs.</p> <p><strong>QUESTION</strong><br/> How can I map my structure to the Modbus channel?</p> <p>Any hint (related to this ;) ) will be appreciated.</p> <p>Thank you very much for your time and help.</p></div>