inputs/outputs mapping issue

2011-11-07
2011-11-09
  • Andoni Crespo

    Andoni Crespo - 2011-11-07

    Good afternoon,

    I am working with UINT variables, but I would like to map then bit by bit because each bit has a determinate meaning. I am trying to do it following the help menu but I cannot do it. Can anybody help me please?

    If I have understood properly I should make an structure of 16 bits and then try to map it, but I do not know how to map it bit by bit

    Thanks in advance

     
  • spfeif

    spfeif - 2011-11-08

    Add a variable in the mapping table like wFaultRegister.

    In the code you can access the bit level of the variable as follows:

    OverTemperatureΒ  := wFaultRegister.0;Β  Β (* Get bit0, all bits are accessed 0 based *)
    UnderTemperature := wFaultRegister.1;
    (* You can get creative and substitute the bits by enumerations and constants *)
    ENUM_OVRTEMPΒ  := 0;Β  Β (* Assume this is part of an enum structure *)
    ENUM_UNDRTEMP := 1;
    OverTemperatureΒ  := wFaultRegister.ENUM_OVRTEMPΒ  ;
    UnderTemperature := wFaultRegister.ENUM_UNDRTEMP ;
    Also easy to create your own FB to do this similar to the UNPACK FB.
    
     
  • Andoni Crespo

    Andoni Crespo - 2011-11-08

    Thanks spfeif for the info but I would like to use this in a mapping input/output card.

    I mean instead of mapping a UINT variable in a %QW0, I would like to map bit by bit like %QB0.0,%QB0.1, %QB0.2...and so on. I have seen on the help menu that is possible but I do not know how to do it

     
  • spfeif

    spfeif - 2011-11-09

    I believe it is not possible. I am assuming what you are calling mapping is from the IO of the target. the target is not configurable. Why does it matter? Just map in the software?

     

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