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Old January 15th, 2020, 10:38 AM   #36
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Originally Posted by PLCnovice61 View Post
So in the end no matter what l select in the status bits the monitor display gives 16 bit result -32768, status table gives a 32 bit result which is correct -42,044,711
Thank you! I finally snagged one cheap off of eBay, but it will not be here until next week. You may think I am asking stupid questions now...

The -32768 16-bit INTEGER result suggests the [Math Overflow Selected S:2/14] bit is not affecting behavior as advertised in the help file.

I have attached a .ZIP; please try the .RSS in that archive; I expect the [Processor Type] in the [General] tab of the [Controller Properties] dialog will need to be changed to match your hardware.

Caveats, Anomalies and FFEs (Fat Finger Errors;-)
  • The N7:20 value in Rung 0002 (MUL.Source_A) should be 20,077,
    • but it is 2,077,
    • whilst the MOV in Rung 0001 correct.
    • but that should not matter in this case,
    • because the result is greater than 16M (2**24)
      • where any FLOAT conversion, if involved, would start dropping low bits
  • The N7:10 value could be -20,423 to match my original example,
    • instead of 20,243
    • but that only affect the actual bits, not the answer to the OP query.
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