Omron CS1W-SLK11-21 - 06-2004, Руководство пользователя

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PLC Network Instructions Section 6-2
Transmission Delay
Number of words transferred
×
0.008 ms + 0.204 ms
Note The I/O response time can increase due to noise or restrictions on the number
of frames that can be transmitted while the data link is operating.
Example In this example, the maximum transmission delay is calculated for an instruc-
tion sending 256 words of data in a system with 32 nodes. Network specifics
are detailed below:
Max. node address: 32
Number of nodes: 32
Number of polled units: 4
Destination node CPU execution processing: Non-synchronous
Number of words:
256
Communications: coaxial cable
Data link: halted
RECV(98) Instruction
Maximum Delay Time The data flow which will yield the maximum transfer interval from the time the
RECV(98) instruction is executed by the user program to the time the SYS-
MAC LINK Unit stores the data in the local Unit’s memory area is described
below.
Note Be sure to take into account the time required for data links and program exe-
cution, which are not included in the following example.
Delay cause Maximum delay (ms)
Link servicing interval (source node) PLC cycle time
Link service processing (source node) 1 ms
Communications cycle time 32
×
0.01 + 32
×
0.075 + 4
×
0.75 +
1.322 = 7.042 ms
Transmission processing 256
×
0.0045 + 4 = 5.152 ms
Transmission delay 256
×
0.008 + 0.204 = 2.252 ms
Reception processing 256
×
0.0045 + 4 = 5.152 ms
Link servicing interval (destination node) CPU Unit cycle time
Link service processing (destination node) 1 ms
Max. transmission delay CPU Unit cycle time (source
node) + CPU Unit cycle time
(destination node) + 21.598 ms
RECV (98) executed Data stored
Link service interval (source node)
Transmission processing (command)
Reception processing (response)
Communications cycle
Reception processing (command)
Link service interval (destination mode)
Transmission delay (command)
Link service processing (source node)
Transmission delay (response)
Transmission processing (response)
Link service processing (destination node)
Maximum transmission delay
Link service processing (source node)