Message Response Time - Omron NX-ECC201 User Manual

Calculating the Message Response Time

Message response time =

• Tcycle: Task period of the primary periodic task in the CPU Unit
• Ts-resp: Slave message response time
*1. If Tcycle divides Ts-resp evenly, there is no need to add 1.
*2. If 256 divides the data byte size of the message response evenly, there is no need to add 1.
NJ-series
CPU Unit
Destination:
EtherCAT
Coupler Unit
Destination:
NX Unit
 Slave Message Response Time: Ts-resp
This is the time from when the message request is received until the EtherCAT Slave Terminal com-
pletes generating the response.
(a) Reading and Writing SDO Data
The destination is the EtherCAT Coupler Unit and the value is as follows:
Ts-resp = 30 to 80 μs
(b) Reading and Writing NX Objects
If the destination is the EtherCAT Coupler Unit, the value is as follows:
Ts-resp = 400 to 1,000 μs
If the destination is an NX Unit, the value is as follows:
Ts-resp = 450 to 7,000 μs
NX-series EtherCAT Coupler Unit User's Manual (W519)
Tcycle + {((Ts-resp ÷Tcycle) + 1
+ {((Data byte size of response message ÷256)
*2
) × Tcycle} + Tcycle
+ 1
Message communications instruction executed.
Primary period
I/O: I/O refreshing
UPG: User program execution
IO UPG
MC: Motion control
System services
Line delay
Frame sent.
EtherCAT Coupler Unit #1
NX Unit number 1
NX Unit number 2
Request received.
NX Unit number 3
EtherCAT Coupler Unit #2
NX Unit number 1
Request received.
NX Unit number 2
Request received.
12 Communications Performance
*1
) × Tcycle}
Primary period
Tcycle Tcycle
MC IO UPG MC IO
Slave message response time: Ts-resp
Response generated.
Primary period Primary period
Tcycle Tcycle
UPG MC IO UPG MC
Response data
sent.
Response
generation
completed.
Response
generation
completed.
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