DEREG: Alarm de-registration
(Original Document)
About us
Description of the function
The DEREG function de-registers an alarm. This is entered into the code of a user diagnostics DFB and records the date when the error disappears in the diagnostics buffer.
NOTE: the alarm remains saved in the diagnostics buffer until the error is acknowledged (for errors that require acknowledgement) and read by all Viewers.
Additional parameters EN and ENO can be configured.
Representation in FBD
Representation applied to an integer:
Representation in LD
Representation applied to an integer:
Representation in IL
Representation applied to an integer: 
LD Error_Id
DEREG
ST Dereg_Status
Representation in ST
Representation applied to an integer: 
Dereg_Status: = DEREG(Error_Id);
Description of parameters
The following table describes the input parameters:
Parameter
Type
Comment
Error_Id
INT
Identifier of the recorded error.
The following table describes the output parameters:
Parameter
Type
Comment
Dereg_Status
INT
Error registration report.
  • if the de-registration is successful, Dereg_Status = 0
  • if the de-registration fails:
    • Dereg_Status = 1: diagnostics buffer not configured
    • Dereg_Status = 21: error identifier incorrect
    • Dereg_Status = 22: no error is registered with this identifier
The system word %SW77 is reserved for reception of the diagnostics DFB de-registration result (use not compulsory but recommended)