Echelon IzoT U60 DIN, Руководство пользователя

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IzoT U60 DIN Network Interface User’s Guide
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The following table summarizes the layout of the data message used in Layer 5 mode
and for the niNETMGMT local network interface command (Layer 2 mode is
required for the IzoT Device Stack EX). When sending local network interface
commands (NI Commands other than niCOMM or niNETMGMT ) that have
additional data, the commands are contained in a data message and they are
preceded by a CpMsg code packet.
BYTE 0 BYTE 1 BYTE 2..N BYTE N+1
Length
(bytes to
follow
except
checksum) NI
Command SICB starting w/ message header Message
Checksum
of bytes 0-N
The following table summarizes the layout of the data message used in Layer 2 mode.
BYTE 0 BYTE 1 BYTE 2..N BYTE N+1
Length
(bytes to
follow
except
checksum) NI
Command Priority/AltPath/DeltaBacklog byte,
NPDU,
CRC (2 Bytes) Message
Checksum
of bytes 0-N
The U60 supports extended messages that may be up to 1280 bytes in length. For
these messages the BYTE 0 length byte will be 0xFF, followed by the MS byte of the
16-bit length, followed by the LS byte of the 16-bit length, followed by the NI
command:
BYTE 0 BYTE 1 BYTE 2 BYTE 3 BYTE 4..N BYTE N+1
0xFF MS byte of
length LS byte of
length (bytes
to follow
except
checksum) NI Command SICB starting
w/ message
header
Message
Checksum
of bytes 0-N
For Layer 2 mode:
BYTE 0 BYTE 1 BYTE 2 BYTE 3 BYTE 4..N BYTE N+1
0xFF MS byte of
length LS byte of
length (bytes
to follow
except
checksum) NI Command Priority/AltPath/
DeltaBacklog
byte,
NPDU,
CRC (2 Bytes)
Message
Checksum
of bytes 0-N