Omron OMNUC W R88A-NCW152-DRT, Manual

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6.8 Communications Using Explicit Messages
6-69
6
D: First Response Word at Local Node
Specify the beginning word of the area for storing responses to messages.
C: First Control Data Word
Specify the beginning word for storing the control data required for message communica-
tions. Preset in consecutive words the required data, as shown below. This data is required
by the DeviceNet Master Unit.
* 1. Set the number of words from the beginning word S.
* 2. Set the number of words from the beginning word D.
* 3. Set the number of retries when there is an error response.
* 4. For Explicit Messages, this must be set to at least 2 s.
* 5. Set bit 15 of word C+4 to 0 (response returned) or 1 (response). For
Explicit Messages, this bit must be set to 0 (response returned).
„ Message Timing
When executing CMND, an AND condition must be set for the ON status of the SYSMAC’s
Network Communications Enabled Flag (A20200 to A20207) and the Master Unit’s Mes-
sage Communications Enabled Flag [bit 12 of word (25
×
unit 1542)].
Word Bits
15 14 to 8 7 to 0
C
Number of command data bytes
∗
1
: 0000 to 021E Hex (0 to 542 bytes)
C+1
Number of response data bytes
∗
2
: 0000 to 021E Hex (0 to 542 bytes)
C+2 Destination network address: 0000 to 007F Hex (0 to 127), 0000 Hex
(local network)
C+3 Destination node address: 00 to 3F Hex
(0 to 63) Destination unit address:
10 to 1F Hex
C+4
Response
∗
5
Communications port
No.: 00 to 07
Number of retries
∗
3
: 00 to 0F Hex
(0 to 15 times)
C+5
Response monitor time
∗
4
: 0000 Hex (2 s), 0001 to FFFF Hex (0.1 to 6,553.5 s (Unit: 0.1 s)
(@)CMND
S
D
C
Message Communications
Enabled Flag
Execution
condition
Network Communications
Enabled Flag