SERCOS file format of the backup file

1. File header of the type ST_SercosFileHeader

2. n * data
a) Parameter header of the type ST_ParamHeader
b) Parameter data as bytes

 

Example of n parameters

1 * ST_SercosFileHeader (268
Bytes)


-----------------------------------------------------

nVersion  
   ( 4 Bytes)

nListType    ( 4 Bytes)

cbCommentLen ( 4 Bytes)

sComment     ( 256 Bytes)


n * (ST_SercosParamHeader + Data)

-----------------------------------------------------

nIDN         ( 2 Bytes)

cbSize       ( 2 Bytes)

nAttrib      ( 4 Bytes)

arrData      (cbSize Bytes),
kann für jeden Parameter verschieden groß sein, je nach Typ oder
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Example of 3 parameters

ST_SercosFileHeader (268 Bytes)
----------------------------------------------------------------------------
nVersion ( 4 Bytes), i.e. = 01 00 00 00 (= 1)
nListType ( 4 Bytes), i.e. = 00 00 00 00 
cbCommentLen ( 4 Bytes), i.e. = 00 00 00 00 (= 0)
sComment ( 256 Bytes), i.e. = 00 00 00 00 00 00 00 ... 00
(256 * 00)
1st parameter ST_SercosParamHeader + Data (10 Bytes)
----------------------------------------------------------------------------
nIDN ( 2 Bytes), i.e. = nnnncbSize( 2 Bytes), i.e. = 02 00 (= 2)nAttrib ( 4 Bytes), i.e. = xx xx xx xx
arrData     (2 Bytes), i.e. = 12 342nd parameter ST_SercosParamHeader + Data (16 Bytes)

----------------------------------------------------------------------------
nIDN ( 2 Bytes), i.e. = nnnncbSize( 2 Bytes), i.e. = 08 00 (= 8)nAttrib( 4 Bytes), i.e. = xx xx xx xx
arrData ( 8 Bytes), i.e. = 12 34 56 78 9a bc de f03rd parameter ST_SercosParamHeader + Data (12 Bytes)
----------------------------------------------------------------------------
nIDN ( 2 Bytes), i.e. = nn nncbSize ( 2 Bytes), i.e. = 04 00 (= 4)nAttrib ( 4 Bytes), i.e. = xx xx xx xx
arrData ( 4 Bytes), i.e. = 12 34 56 78

 

TYPE ST_SercosFileHeader (268 bytes)

The file header of the Sercos backup file is based on the ST_SercosFileHeader structure.

TYPE ST_SercosFileHeader :
STRUCT
    nVersion      : UDINT;(* 4 Bytes *)
    nListType     : UDINT;(* 4 Bytes *)
    cbCommentLen  : UDINT;(* 4 Bytes *)
    sComment      : T_MaxString;(* 256 Bytes *)
END_STRUCT
END_TYPE

nVersion: contains the file version, momentarily 1.

nListType: contains the IDN parameter list that was used for the backup. The default value is 192 (list of all backup parameters): the value is 0 in case of user-defined backup list. Alternatively, the list of all Sercos parameters (IDN 17) can be used. The restore, however, requires the list from parameter 192 or the user-defined list (0).

cbCommentLen: Length of the comment of the backup file.

sComment: Comment of the backup file. The string is written with all 256 characters.

TYPE ST_SercosParamHeader (8 bytes)

In the backup file, the file header is followed by a parameter header of the type ST_SercosParamHeader for each parameter.

TYPE ST_SercosParamHeader :
STRUCT
    nIDN     : UINT;(* 2 Bytes *)
    cbSize   : UINT;(* 2 Bytes *)
    nAttrib  : DWORD;(* 4 Bytes *)
END_STRUCT
END_TYPE

nIDN: Sercos parameter number.

cbSize: Length of the data in bytes that follow this header. Can be different for each parameter, depending on the parameter type or list length.

nAttrib: Attribute of the Sercos parameter (see ST_SercosParamData); required for the determination of length and data type.

Parameter data (cbSize bytes)

The data directly follow each Sercos parameter header in the backup file. The number of data bytes is saved in the parameter header in cbSize.

Requirements

Development environment

Target platform

IO hardware

PLC libraries to be integrated (category group)

TwinCAT v3.1.0

PC (x86)

Sercans SCS-P ISA; Sercans SCS-P PCI;
Beckhoff FC750x PCI

Tc2_IoFunctions (IO)