Festo EMCA-EC-67 CO Series, Описание

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A Festo Parameter Channel (FPC)
230 Festo – EMCA-EC-C-HP-EN – 2017-11e – English
A.4.4 Parameter file and user data package
Parameter file
The parameter file functions as a data container of the complete parameter set of an EMCA. With it,
parameter settings can be transmitted between identical EMCAs.
The parameter file consists of the 3 parts header, data range and CRC test value.
File beginning
256 bytes Header
n bytes Data range (objects)
2 bytes CRC test value
File end
Fig. A.2 Structure of parameter file
With an upload of the parameter file, the parameter values are transmitted from the permanent data
memory of the EMCA.
If the parameters of the EMCA were changed during execution time, although they are active, they are
not stored in the permanent memory of the EMCA and so are lost after a restart. With PNU 127:2, the
current parameterisation can be stored in the permanent data memory.
User data package
The parameter file is divided into 6-byte blocks for transmission and put back together after transmis­
sion.
The LSB (least significant bit) of the user data is in byte 3 (Little endian), that is, directly after the pro­
tocol header of the 8 bytes of the EFPC. If no user data are present, all bits equal zero.
If all 6 bytes from the last transmitted data telegram are no longer needed for the parameter file, the
remaining bytes are filled with zeros. The parameter file size, which was transmitted at the start, shows
up to where the data have to be evaluated.
Rotation of the user data
For CANopen and EtherNet/IP, rotation of the byte order is required. Rotation of the user data is per­
formed as follows:
Data 1st byte order 2nd byte order
User data without rotation Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 Byte 8
User data with rotation Byte 4 Byte 3 Byte 8 Byte 7 Byte 6 Byte 5
Tab. A.11 Rotation of the user data
The size of the transmitted parameter file is in byte 3 and byte 4.