Omron S8AS, Руководство пользователя

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Frame Structure
Section 6-2
6-2 Frame Structure
6-2-1 Command Frame Structure
STX This code, 02 hex, indicates the beginning of a communica-
tions frame (text). This code must always be set as the first
byte.
When another STX code is received during reception, the
reception starts again from the point where the STX was
received.
Node No.
(Node address) • The node address identifies the destination node.
• The node address can be set to 00 to 32.
• There will be no response to a transmission with an invalid
node address.
Subaddress The subaddress is not used in the S8AS. Always set the sub-
address to “00.”
SID (Service ID) The SID is not used in the S8AS. Always set the SID to “0.”
FINS-mini
command text The command and required text are placed here. Refer to 6-2-
3 FINS-mini Structure for details.
ETX This code, 03 hex, indicates the end of text.
BCC This is the block check character.
The BCC is calculated by taking the exclusive OR of all bytes
from the node number to the ETX.
S T X
0 1 0 0 0
E T X
1 2 2 1 1 1
Text
Node No. Subaddress FINS-mini command text
BCC calculation range
BCC SID