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    <p>You've already figured it out, it seems that you just don't realize it. The conversion <code>DWORD_TO_REAL</code> is taking the integer (hex) value stored in <code>4bytesData</code> and converting it to IEEE754 REAL format. </p> <p>This is not what you want to do. <code>4479FFFF</code> is <strong>already</strong> in IEEE754 REAL format - you're taking that value, interpreting the REAL as a DWORD, and then converting the DWORD value to a REAL. The short answer is that you don't need the conversion - <code>4bytesData</code> is already in the correct format.</p> <p><strong>edit</strong> </p> <p>follow up on comments : </p> <p><img src="https://i.stack.imgur.com/i9wEy.png" alt="enter image description here"></p> <p>here FunctionBlock2 delclares rIn(REAL), rOut(REAL) and sets <code>rOut:=rIn;</code>. This gets around the forced typecasting of ST. Nothing is changing about the data stored in <code>D2000</code> here - it's the same binary data. The top function block is storing it into memory and the bottom one is reading it from memory. The only difference is that the top rung is interpreting it as a DWORD (for display purposes) and the bottom rung is interpreting it as REAL. </p> <p><em>edit</em></p> <p>I've been reading the Beckhoff manual. It seems you may have other options. Try perhaps <a href="http://infosys.beckhoff.com/english.php?content=../content/1033/tcplccontrol/html/tcplcctrl_variables_allocated.htm&amp;id=14211" rel="nofollow noreferrer">declaring a DWORD and REAL at the same memory location</a>. If not, perhaps <a href="http://infosys.beckhoff.com/english.php?content=../content/1033/tcplccontrol/html/tcplcctrl_%5E.htm&amp;id=14183" rel="nofollow noreferrer">pointers would let you do it</a> (not sure if type restrictions also apply to pointers with Beckhoff?) </p>
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    1. POPLC Structured text, convert decimal to real(float). Not getting the value I expect. (IEEE-754)
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    1. COThanks for the answer. You are correct that I don't have to use the "DWORD_TO_REAL" conversion. But I'm still getting the "1.148846e+009" value if I remove that, so its still the same. The 4bytesData is "1148846079".
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    2. CO@hijack it's probably doing the conversion for you automatically, then, even though you remove the explicit conversion...depends on the PLC you are using. Try declaring 4bytesData as REAL type rather than DWORD.
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    3. COYeah probably it is. (I'm using Beckhoff) When I'm doing the shifting of the bytes into the 4bytesData I get an error: "Type mismatch in parameter, cannot convert 'REAL' to 'BYTE'.
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