Requirement for value status

Requirement for value status

Requirement for status of object value

DDE reference that enables to get the status of object value:

= D_2000|STATUS!objname

D_2000 - DDE Server name (required).

STATUS - requirement for status of object.

objname - object name.

DDE reference returns a string in the format "z1;z2;".

  • z1 can be one of the characters: N, U, O, D or E.

    N

    Normal

    Valid value.

    U

    Undefined

    Undefined value.

    O

    Out of Range

    Value out of range.

    D

    Error

    Error.

    E

    Div by Zero

    Divide by zero.

  • if z1 is "N", DDE reference returns also the second part of string - z2. This part of the string consists of two characters.

    I_

    In Limit

    The value from the interval <LL..HL>.

    VL

    Very Low Limit

    The value is lower than VLL.

    L_

    Low Limit

    The value is lower than LL.

    H_

    High Limit

    The value is higher than HL.

    VH

    Very High Limit

    The value is higher than VHL.

    T_

    Transient

    Transient status - there was executed a command to set the object value, but there has not been verified the setting of value by backward reading yet.

    D_

    Default

    Default value.

    W_

    Weak

    Weak value - the system does not consider this value as valid because there have not been fulfilled all the conditions of its validity.

    WC

    Weak Cmd

    Weak Command.

    WA

    Weak Ans

    Weak Answer.

    LP

    Limits Problem

    Crossing of the dynamic limits - the condition VLL<LL<HL<VHL has been broken.

The string that returns DDE reference D2000|STATUS!objname can be converted into:

  1. label of the value status - by the function GetValueStatusStr,

  2. label of the value limit - by the function GetValueLimitStr.

The example of DDE reference is - here.